from __future__ import annotations

import re
import sys
from pathlib import Path
from typing import Any, Dict, List, Optional, Tuple

import httpx

from SYS.logger import debug, log
from SYS.utils_constant import mime_maps

from Store._base import Store

_HYDRUS_INIT_CHECK_CACHE: dict[tuple[str,
                                     str],
                               tuple[bool,
                                     Optional[str]]] = {}


class HydrusNetwork(Store):
    """File storage backend for Hydrus client.

    Each instance represents a specific Hydrus client connection.
    Maintains its own HydrusClient.
    """

    def _log_prefix(self) -> str:
        store_name = getattr(self, "NAME", None) or "unknown"
        return f"[hydrusnetwork:{store_name}]"

    def __new__(cls, *args: Any, **kwargs: Any) -> "HydrusNetwork":
        instance = super().__new__(cls)
        name = kwargs.get("NAME")
        api = kwargs.get("API")
        url = kwargs.get("URL")
        if name is not None:
            setattr(instance, "NAME", str(name))
        if api is not None:
            setattr(instance, "API", str(api))
        if url is not None:
            setattr(instance, "URL", str(url))
        return instance

    setattr(__new__, "keys", ("NAME", "API", "URL"))

    def __init__(
        self,
        instance_name: Optional[str] = None,
        api_key: Optional[str] = None,
        url: Optional[str] = None,
        *,
        NAME: Optional[str] = None,
        API: Optional[str] = None,
        URL: Optional[str] = None,
    ) -> None:
        """Initialize Hydrus storage backend.

        Args:
            instance_name: Name of this Hydrus instance (e.g., 'home', 'work')
            api_key: Hydrus Client API access key
            url: Hydrus client URL (e.g., 'http://192.168.1.230:45869')
        """
        from API.HydrusNetwork import HydrusNetwork as HydrusClient

        if instance_name is None and NAME is not None:
            instance_name = str(NAME)
        if api_key is None and API is not None:
            api_key = str(API)
        if url is None and URL is not None:
            url = str(URL)

        if not instance_name or not api_key or not url:
            raise ValueError("HydrusNetwork requires NAME, API, and URL")

        self.NAME = instance_name
        self.API = api_key
        self.URL = url.rstrip("/")

        # Total count (best-effort, used for startup diagnostics)
        self.total_count: Optional[int] = None

        # Self health-check: validate the URL is reachable and the access key is accepted.
        # This MUST NOT attempt to acquire a session key.
        cache_key = (self.URL, self.API)
        cached = _HYDRUS_INIT_CHECK_CACHE.get(cache_key)
        if cached is not None:
            ok, err = cached
            if not ok:
                raise RuntimeError(
                    f"Hydrus '{self.NAME}' unavailable: {err or 'Unavailable'}"
                )
        else:
            api_version_url = f"{self.URL}/api_version"
            verify_key_url = f"{self.URL}/verify_access_key"
            try:
                with httpx.Client(timeout=5.0,
                                  verify=False,
                                  follow_redirects=True) as client:
                    version_resp = client.get(api_version_url)
                    version_resp.raise_for_status()
                    version_payload = version_resp.json()
                    if not isinstance(version_payload, dict):
                        raise RuntimeError(
                            "Hydrus /api_version returned an unexpected response"
                        )

                    verify_resp = client.get(
                        verify_key_url,
                        headers={
                            "Hydrus-Client-API-Access-Key": self.API
                        },
                    )
                    verify_resp.raise_for_status()
                    verify_payload = verify_resp.json()
                    if not isinstance(verify_payload, dict):
                        raise RuntimeError(
                            "Hydrus /verify_access_key returned an unexpected response"
                        )

                _HYDRUS_INIT_CHECK_CACHE[cache_key] = (True, None)
            except Exception as exc:
                err = str(exc)
                _HYDRUS_INIT_CHECK_CACHE[cache_key] = (False, err)
                raise RuntimeError(f"Hydrus '{self.NAME}' unavailable: {err}") from exc

        # Create a persistent client for this instance (auth via access key by default).
        self._client = HydrusClient(
            url=self.URL,
            access_key=self.API,
            instance_name=self.NAME
        )

        # Best-effort total count (used for startup diagnostics). Avoid heavy payloads.
        # Some Hydrus setups appear to return no count via the CBOR client for this endpoint,
        # so prefer a direct JSON request with a short timeout.
        try:
            self.get_total_count(refresh=True)
        except Exception:
            pass

    def get_total_count(self, *, refresh: bool = False) -> Optional[int]:
        """Best-effort total file count for this Hydrus instance.

        Intended for diagnostics (e.g., REPL startup checks). This should be fast,
        and it MUST NOT raise.
        """
        if self.total_count is not None and not refresh:
            return self.total_count

        # 1) Prefer a direct JSON request (fast + avoids CBOR edge cases).
        try:
            import json as _json

            url = f"{self.URL}/get_files/search_files"
            params = {
                "tags": _json.dumps(["system:everything"]),
                "return_hashes": "false",
                "return_file_ids": "false",
                "return_file_count": "true",
            }
            headers = {
                "Hydrus-Client-API-Access-Key": self.API,
                "Accept": "application/json",
            }
            with httpx.Client(timeout=5.0,
                              verify=False,
                              follow_redirects=True) as client:
                resp = client.get(url, params=params, headers=headers)
                resp.raise_for_status()
                payload = resp.json()

            count_val = None
            if isinstance(payload, dict):
                count_val = payload.get("file_count")
                if count_val is None:
                    count_val = payload.get("file_count_inclusive")
                if count_val is None:
                    count_val = payload.get("num_files")
            if isinstance(count_val, int):
                self.total_count = count_val
                return self.total_count
        except Exception as exc:
            debug(
                f"{self._log_prefix()} total count (json) unavailable: {exc}",
                file=sys.stderr
            )

        # 2) Fallback to the API client (CBOR).
        try:
            payload = self._client.search_files(
                tags=["system:everything"],
                return_hashes=False,
                return_file_ids=False,
                return_file_count=True,
            )
            count_val = None
            if isinstance(payload, dict):
                count_val = payload.get("file_count")
                if count_val is None:
                    count_val = payload.get("file_count_inclusive")
                if count_val is None:
                    count_val = payload.get("num_files")
            if isinstance(count_val, int):
                self.total_count = count_val
                return self.total_count
        except Exception as exc:
            debug(
                f"{self._log_prefix()} total count (client) unavailable: {exc}",
                file=sys.stderr
            )

        return self.total_count

    def name(self) -> str:
        return self.NAME

    def get_name(self) -> str:
        return self.NAME

    def add_file(self, file_path: Path, **kwargs: Any) -> str:
        """Upload file to Hydrus with full metadata support.

        Args:
            file_path: Path to the file to upload
            tag: Optional list of tag values to add
            url: Optional list of url to associate with the file
            title: Optional title (will be added as 'title:value' tag)

        Returns:
            File hash from Hydrus

        Raises:
            Exception: If upload fails
        """
        from SYS.utils import sha256_file

        tag_list = kwargs.get("tag", [])
        url = kwargs.get("url", [])
        title = kwargs.get("title")

        # Add title to tags if provided and not already present
        if title:
            title_tag = f"title:{title}".strip().lower()
            if not any(str(candidate).lower().startswith("title:")
                       for candidate in tag_list):
                tag_list = [title_tag] + list(tag_list)

        # Hydrus is lowercase-only tags; normalize here for consistency.
        tag_list = [
            str(t).strip().lower() for t in (tag_list or [])
            if isinstance(t, str) and str(t).strip()
        ]

        try:
            # Compute file hash
            file_hash = sha256_file(file_path)
            debug(f"{self._log_prefix()} file hash: {file_hash}")

            # Use persistent client with session key
            client = self._client
            if client is None:
                raise Exception("Hydrus client unavailable")

            # Check if file already exists in Hydrus
            file_exists = False
            try:
                metadata = client.fetch_file_metadata(
                    hashes=[file_hash],
                    include_service_keys_to_tags=False,
                    include_file_url=False,
                    include_duration=False,
                    include_size=False,
                    include_mime=False,
                )
                if metadata and isinstance(metadata, dict):
                    metas = metadata.get("metadata", [])
                    if isinstance(metas, list) and metas:
                        # Hydrus returns placeholder rows for unknown hashes.
                        # Only treat as a real duplicate if it has a concrete file_id.
                        for meta in metas:
                            if isinstance(meta,
                                          dict) and meta.get("file_id") is not None:
                                file_exists = True
                                break
                if file_exists:
                    log(
                        f"ℹ️  Duplicate detected - file already in Hydrus with hash: {file_hash}",
                        file=sys.stderr,
                    )
            except Exception:
                pass

            # If Hydrus reports an existing file, it may be in trash. Best-effort restore it to 'my files'.
            # This keeps behavior aligned with user expectation: "use API only" and ensure it lands in my files.
            if file_exists:
                try:
                    client.undelete_files([file_hash])
                except Exception:
                    pass

            # Upload file if not already present
            if not file_exists:
                log(
                    f"{self._log_prefix()} Uploading: {file_path.name}",
                    file=sys.stderr
                )
                response = client.add_file(file_path)

                # Extract hash from response
                hydrus_hash: Optional[str] = None
                if isinstance(response, dict):
                    hydrus_hash = response.get("hash") or response.get("file_hash")
                    if not hydrus_hash:
                        hashes = response.get("hashes")
                        if isinstance(hashes, list) and hashes:
                            hydrus_hash = hashes[0]

                if not hydrus_hash:
                    raise Exception(f"Hydrus response missing file hash: {response}")

                file_hash = hydrus_hash
                log(f"{self._log_prefix()} hash: {file_hash}", file=sys.stderr)

            # Add tags if provided (both for new and existing files)
            if tag_list:
                try:
                    # Use default tag service
                    service_name = "my tags"
                except Exception:
                    service_name = "my tags"

                try:
                    debug(
                        f"{self._log_prefix()} Adding {len(tag_list)} tag(s): {tag_list}"
                    )
                    client.add_tag(file_hash, tag_list, service_name)
                    log(
                        f"{self._log_prefix()} Tags added via '{service_name}'",
                        file=sys.stderr
                    )
                except Exception as exc:
                    log(
                        f"{self._log_prefix()} ⚠️  Failed to add tags: {exc}",
                        file=sys.stderr
                    )

            # Associate url if provided (both for new and existing files)
            if url:
                log(
                    f"{self._log_prefix()} Associating {len(url)} URL(s) with file",
                    file=sys.stderr
                )
                for url in url:
                    if url:
                        try:
                            client.associate_url(file_hash, str(url))
                            debug(f"{self._log_prefix()} Associated URL: {url}")
                        except Exception as exc:
                            log(
                                f"{self._log_prefix()} ⚠️  Failed to associate URL {url}: {exc}",
                                file=sys.stderr,
                            )

            return file_hash

        except Exception as exc:
            log(f"{self._log_prefix()} ❌ upload failed: {exc}", file=sys.stderr)
            raise

    def search(self, query: str, **kwargs: Any) -> list[Dict[str, Any]]:
        """Search Hydrus database for files matching query.

        Args:
            query: Search query (tags, filenames, hashes, etc.)
            limit: Maximum number of results to return (default: 100)

        Returns:
            List of dicts with 'name', 'hash', 'size', 'tags' fields

        Example:
            results = storage["hydrus"].search("artist:john_doe music")
            results = storage["hydrus"].search("Simple Man")
        """
        limit = kwargs.get("limit", 100)

        try:
            client = self._client
            if client is None:
                raise Exception("Hydrus client unavailable")

            prefix = self._log_prefix()
            debug(f"{prefix} Searching for: {query}")

            def _extract_urls(meta_obj: Any) -> list[str]:
                if not isinstance(meta_obj, dict):
                    return []
                raw = meta_obj.get("url")
                if raw is None:
                    raw = meta_obj.get("urls")
                if isinstance(raw, str):
                    val = raw.strip()
                    return [val] if val else []
                if isinstance(raw, list):
                    out: list[str] = []
                    for item in raw:
                        if not isinstance(item, str):
                            continue
                        s = item.strip()
                        if s:
                            out.append(s)
                    return out
                return []

            def _iter_url_filtered_metadata(
                url_value: str | None,
                want_any: bool,
                fetch_limit: int
            ) -> list[dict[str,
                           Any]]:
                """Best-effort URL search by scanning Hydrus metadata with include_file_url=True."""

                # First try a fast system predicate if Hydrus supports it.
                candidate_file_ids: list[int] = []
                try:
                    if want_any:
                        predicate = "system:has url"
                        url_search = client.search_files(
                            tags=[predicate],
                            return_hashes=False,
                            return_file_ids=True,
                            return_file_count=False,
                        )
                        ids = url_search.get("file_ids",
                                             []) if isinstance(url_search,
                                                               dict) else []
                        if isinstance(ids, list):
                            candidate_file_ids = [
                                int(x) for x in ids
                                if isinstance(x, (int, float,
                                                  str)) and str(x).strip().isdigit()
                            ]
                except Exception:
                    candidate_file_ids = []

                if not candidate_file_ids:
                    # Fallback: scan from system:everything and filter by URL substring.
                    everything = client.search_files(
                        tags=["system:everything"],
                        return_hashes=False,
                        return_file_ids=True,
                        return_file_count=False,
                    )
                    ids = everything.get("file_ids",
                                         []) if isinstance(everything,
                                                           dict) else []
                    if isinstance(ids, list):
                        candidate_file_ids = [
                            int(x) for x in ids if isinstance(x, (int, float))
                        ]

                if not candidate_file_ids:
                    return []

                needle = (url_value or "").strip().lower()
                chunk_size = 200
                out: list[dict[str, Any]] = []

                for start in range(0, len(candidate_file_ids), chunk_size):
                    if len(out) >= fetch_limit:
                        break
                    chunk = candidate_file_ids[start:start + chunk_size]
                    try:
                        payload = client.fetch_file_metadata(
                            file_ids=chunk,
                            include_file_url=True,
                            include_service_keys_to_tags=True,
                            include_duration=True,
                            include_size=True,
                            include_mime=True,
                        )
                    except Exception:
                        continue

                    metas = payload.get("metadata",
                                        []) if isinstance(payload,
                                                          dict) else []
                    if not isinstance(metas, list):
                        continue

                    for meta in metas:
                        if not isinstance(meta, dict):
                            continue
                        urls = _extract_urls(meta)
                        if not urls:
                            continue
                        if want_any:
                            out.append(meta)
                            if len(out) >= fetch_limit:
                                break
                            continue

                        if not needle:
                            continue
                        if any(needle in u.lower() for u in urls):
                            out.append(meta)
                            if len(out) >= fetch_limit:
                                break

                return out

            query_lower = query.lower().strip()

            # Support `ext:<value>` anywhere in the query. We filter results by the
            # Hydrus metadata extension field.
            def _normalize_ext_filter(value: str) -> str:
                v = str(value or "").strip().lower().lstrip(".")
                v = "".join(ch for ch in v if ch.isalnum())
                return v

            ext_filter: str | None = None
            ext_only: bool = False
            try:
                m = re.search(r"\bext:([^\s,]+)", query_lower)
                if not m:
                    m = re.search(r"\bextension:([^\s,]+)", query_lower)
                if m:
                    ext_filter = _normalize_ext_filter(m.group(1)) or None
                    query_lower = re.sub(
                        r"\s*\b(?:ext|extension):[^\s,]+",
                        " ",
                        query_lower
                    )
                    query_lower = re.sub(r"\s{2,}", " ", query_lower).strip().strip(",")
                    query = query_lower
                    if ext_filter and not query_lower:
                        query = "*"
                        query_lower = "*"
                        ext_only = True
            except Exception:
                ext_filter = None
                ext_only = False

            # Split into meaningful terms for AND logic.
            # Avoid punctuation tokens like '-' that would make matching brittle.
            search_terms = [t for t in re.findall(r"[a-z0-9]+", query_lower) if t]

            # Special case: url:* and url:<value>
            metadata_list: list[dict[str, Any]] | None = None
            if ":" in query_lower and not query_lower.startswith(":"):
                namespace, pattern = query_lower.split(":", 1)
                namespace = namespace.strip().lower()
                pattern = pattern.strip()
                if namespace == "url":
                    if not pattern or pattern == "*":
                        metadata_list = _iter_url_filtered_metadata(
                            None,
                            want_any=True,
                            fetch_limit=int(limit) if limit else 100
                        )
                    else:
                        # Fast-path: exact URL via /add_urls/get_url_files when a full URL is provided.
                        try:
                            if pattern.startswith("http://") or pattern.startswith(
                                    "https://"):
                                from API.HydrusNetwork import HydrusRequestSpec

                                spec = HydrusRequestSpec(
                                    method="GET",
                                    endpoint="/add_urls/get_url_files",
                                    query={
                                        "url": pattern
                                    },
                                )
                                response = client._perform_request(
                                    spec
                                )  # type: ignore[attr-defined]
                                hashes: list[str] = []
                                file_ids: list[int] = []
                                if isinstance(response, dict):
                                    raw_hashes = response.get("hashes") or response.get(
                                        "file_hashes"
                                    )
                                    if isinstance(raw_hashes, list):
                                        hashes = [
                                            str(h).strip() for h in raw_hashes
                                            if isinstance(h, str) and str(h).strip()
                                        ]
                                    raw_ids = response.get("file_ids")
                                    if isinstance(raw_ids, list):
                                        for item in raw_ids:
                                            try:
                                                file_ids.append(int(item))
                                            except (TypeError, ValueError):
                                                continue

                                if file_ids:
                                    payload = client.fetch_file_metadata(
                                        file_ids=file_ids,
                                        include_file_url=True,
                                        include_service_keys_to_tags=True,
                                        include_duration=True,
                                        include_size=True,
                                        include_mime=True,
                                    )
                                    metas = (
                                        payload.get("metadata",
                                                    []) if isinstance(payload,
                                                                      dict) else []
                                    )
                                    if isinstance(metas, list):
                                        metadata_list = [
                                            m for m in metas if isinstance(m, dict)
                                        ]
                                elif hashes:
                                    payload = client.fetch_file_metadata(
                                        hashes=hashes,
                                        include_file_url=True,
                                        include_service_keys_to_tags=True,
                                        include_duration=True,
                                        include_size=True,
                                        include_mime=True,
                                    )
                                    metas = (
                                        payload.get("metadata",
                                                    []) if isinstance(payload,
                                                                      dict) else []
                                    )
                                    if isinstance(metas, list):
                                        metadata_list = [
                                            m for m in metas if isinstance(m, dict)
                                        ]
                        except Exception:
                            metadata_list = None

                        # Fallback: substring scan
                        if metadata_list is None:
                            metadata_list = _iter_url_filtered_metadata(
                                pattern,
                                want_any=False,
                                fetch_limit=int(limit) if limit else 100
                            )

            # Parse the query into tags
            # "*" means "match all" - use system:everything tag in Hydrus
            # If query has explicit namespace, use it as a tag search.
            # If query is free-form, search BOTH:
            #   - title:*term*  (title: is the only namespace searched implicitly)
            #   - *term*        (freeform tags; we will filter out other namespace matches client-side)
            tags: list[str] = []
            freeform_union_search: bool = False
            title_predicates: list[str] = []
            freeform_predicates: list[str] = []

            if query.strip() == "*":
                tags = ["system:everything"]
            elif ":" in query_lower:
                tags = [query_lower]
            else:
                freeform_union_search = True
                if search_terms:
                    # Hydrus supports wildcard matching primarily as a prefix (e.g., tag*).
                    # Use per-term prefix matching for both title: and freeform tags.
                    title_predicates = [f"title:{term}*" for term in search_terms]
                    freeform_predicates = [f"{term}*" for term in search_terms]
                else:
                    # If we can't extract alnum terms, fall back to the raw query text.
                    title_predicates = [f"title:{query_lower}*"]
                    freeform_predicates = [f"{query_lower}*"]

            # Search files with the tags (unless url: search already produced metadata)
            results = []

            def _extract_search_ids(payload: Any) -> tuple[list[int], list[str]]:
                if not isinstance(payload, dict):
                    return [], []
                raw_ids = payload.get("file_ids", [])
                raw_hashes = payload.get("hashes", [])
                ids_out: list[int] = []
                hashes_out: list[str] = []
                if isinstance(raw_ids, list):
                    for item in raw_ids:
                        try:
                            ids_out.append(int(item))
                        except (TypeError, ValueError):
                            continue
                if isinstance(raw_hashes, list):
                    hashes_out = [
                        str(h).strip() for h in raw_hashes
                        if isinstance(h, str) and str(h).strip()
                    ]
                return ids_out, hashes_out

            if metadata_list is None:
                file_ids: list[int] = []
                hashes: list[str] = []

                if freeform_union_search:
                    if not title_predicates and not freeform_predicates:
                        debug(f"{prefix} 0 result(s)")
                        return []

                    payloads: list[Any] = []
                    try:
                        payloads.append(
                            client.search_files(
                                tags=title_predicates,
                                return_hashes=True,
                                return_file_ids=True,
                            )
                        )
                    except Exception:
                        pass

                    try:
                        payloads.append(
                            client.search_files(
                                tags=freeform_predicates,
                                return_hashes=True,
                                return_file_ids=True,
                            )
                        )
                    except Exception:
                        pass

                    id_set: set[int] = set()
                    hash_set: set[str] = set()
                    for payload in payloads:
                        ids_part, hashes_part = _extract_search_ids(payload)
                        for fid in ids_part:
                            id_set.add(fid)
                        for hh in hashes_part:
                            hash_set.add(hh)
                    file_ids = list(id_set)
                    hashes = list(hash_set)
                else:
                    if not tags:
                        debug(f"{prefix} 0 result(s)")
                        return []

                    search_result = client.search_files(
                        tags=tags,
                        return_hashes=True,
                        return_file_ids=True
                    )
                    file_ids, hashes = _extract_search_ids(search_result)

                # Fast path: ext-only search. Avoid fetching metadata for an unbounded
                # system:everything result set; fetch in chunks until we have enough.
                if ext_only and ext_filter:
                    results: list[dict[str, Any]] = []
                    if not file_ids and not hashes:
                        debug(f"{prefix} 0 result(s)")
                        return []

                    # Prefer file_ids if available.
                    if file_ids:
                        chunk_size = 200
                        for start in range(0, len(file_ids), chunk_size):
                            if len(results) >= limit:
                                break
                            chunk = file_ids[start:start + chunk_size]
                            try:
                                payload = client.fetch_file_metadata(
                                    file_ids=chunk,
                                    include_service_keys_to_tags=True,
                                    include_file_url=False,
                                    include_duration=True,
                                    include_size=True,
                                    include_mime=True,
                                )
                            except Exception:
                                continue
                            metas = payload.get("metadata",
                                                []) if isinstance(payload,
                                                                  dict) else []
                            if not isinstance(metas, list):
                                continue
                            for meta in metas:
                                if len(results) >= limit:
                                    break
                                if not isinstance(meta, dict):
                                    continue
                                mime_type = meta.get("mime")
                                ext = str(meta.get("ext") or "").strip().lstrip(".")
                                if not ext and mime_type:
                                    for category in mime_maps.values():
                                        for _ext_key, info in category.items():
                                            if mime_type in info.get("mimes", []):
                                                ext = str(info.get("ext",
                                                                   "")
                                                          ).strip().lstrip(".")
                                                break
                                        if ext:
                                            break
                                if _normalize_ext_filter(ext) != ext_filter:
                                    continue

                                file_id = meta.get("file_id")
                                hash_hex = meta.get("hash")
                                size = meta.get("size", 0)

                                tags_set = meta.get("tags",
                                                    {})
                                all_tags: list[str] = []
                                title = f"Hydrus File {file_id}"
                                if isinstance(tags_set, dict):

                                    def _collect(tag_list: Any) -> None:
                                        nonlocal title
                                        if not isinstance(tag_list, list):
                                            return
                                        for tag in tag_list:
                                            tag_text = str(tag) if tag else ""
                                            if not tag_text:
                                                continue
                                            tag_l = tag_text.strip().lower()
                                            if not tag_l:
                                                continue
                                            all_tags.append(tag_l)
                                            if (tag_l.startswith("title:") and title
                                                    == f"Hydrus File {file_id}"):
                                                title = tag_l.split(":", 1)[1].strip()

                                    for _service_name, service_tags in tags_set.items():
                                        if not isinstance(service_tags, dict):
                                            continue
                                        storage_tags = service_tags.get(
                                            "storage_tags",
                                            {}
                                        )
                                        if isinstance(storage_tags, dict):
                                            for tag_list in storage_tags.values():
                                                _collect(tag_list)
                                        display_tags = service_tags.get(
                                            "display_tags",
                                            []
                                        )
                                        _collect(display_tags)

                                file_url = f"{self.URL.rstrip('/')}/get_files/file?hash={hash_hex}"
                                results.append(
                                    {
                                        "hash": hash_hex,
                                        "url": file_url,
                                        "name": title,
                                        "title": title,
                                        "size": size,
                                        "size_bytes": size,
                                        "store": self.NAME,
                                        "tag": all_tags,
                                        "file_id": file_id,
                                        "mime": mime_type,
                                        "ext": ext,
                                    }
                                )

                        debug(f"{prefix} {len(results)} result(s)")
                        return results[:limit]

                    # If we only got hashes, fall back to the normal flow below.

                if not file_ids and not hashes:
                    debug(f"{prefix} 0 result(s)")
                    return []

                if file_ids:
                    metadata = client.fetch_file_metadata(
                        file_ids=file_ids,
                        include_service_keys_to_tags=True,
                        include_file_url=False,
                        include_duration=True,
                        include_size=True,
                        include_mime=True,
                    )
                    metadata_list = metadata.get("metadata", [])
                elif hashes:
                    metadata = client.fetch_file_metadata(
                        hashes=hashes,
                        include_service_keys_to_tags=True,
                        include_file_url=False,
                        include_duration=True,
                        include_size=True,
                        include_mime=True,
                    )
                    metadata_list = metadata.get("metadata", [])
                else:
                    metadata_list = []

                # If our free-text searches produce nothing (or nothing survived downstream filtering), fallback to scanning.
                if (not metadata_list) and (query_lower
                                            != "*") and (":" not in query_lower):
                    try:
                        search_result = client.search_files(
                            tags=["system:everything"],
                            return_hashes=True,
                            return_file_ids=True,
                        )
                        file_ids, hashes = _extract_search_ids(search_result)

                        if file_ids:
                            metadata = client.fetch_file_metadata(
                                file_ids=file_ids,
                                include_service_keys_to_tags=True,
                                include_file_url=False,
                                include_duration=True,
                                include_size=True,
                                include_mime=True,
                            )
                            metadata_list = metadata.get("metadata", [])
                        elif hashes:
                            metadata = client.fetch_file_metadata(
                                hashes=hashes,
                                include_service_keys_to_tags=True,
                                include_file_url=False,
                                include_duration=True,
                                include_size=True,
                                include_mime=True,
                            )
                            metadata_list = metadata.get("metadata", [])
                    except Exception:
                        pass

            if not isinstance(metadata_list, list):
                metadata_list = []

            for meta in metadata_list:
                if len(results) >= limit:
                    break

                file_id = meta.get("file_id")
                hash_hex = meta.get("hash")
                size = meta.get("size", 0)

                # Get tags for this file and extract title
                tags_set = meta.get("tags",
                                    {})
                all_tags = []
                title = f"Hydrus File {file_id}"  # Default fallback
                all_tags_str = ""  # For substring matching

                # debug(f"[HydrusBackend.search] Processing file_id={file_id}, tags type={type(tags_set)}")

                if isinstance(tags_set, dict):
                    # Collect both storage_tags and display_tags to capture siblings/parents and ensure title: is seen
                    def _collect(tag_list: Any) -> None:
                        nonlocal title, all_tags_str
                        if not isinstance(tag_list, list):
                            return
                        for tag in tag_list:
                            tag_text = str(tag) if tag else ""
                            if not tag_text:
                                continue
                            tag_l = tag_text.strip().lower()
                            if not tag_l:
                                continue
                            all_tags.append(tag_l)
                            all_tags_str += " " + tag_l
                            if tag_l.startswith("title:"
                                                ) and title == f"Hydrus File {file_id}":
                                title = tag_l.split(":", 1)[1].strip()

                    for _service_name, service_tags in tags_set.items():
                        if not isinstance(service_tags, dict):
                            continue

                        storage_tags = service_tags.get("storage_tags",
                                                        {})
                        if isinstance(storage_tags, dict):
                            for tag_list in storage_tags.values():
                                _collect(tag_list)

                        display_tags = service_tags.get("display_tags", [])
                        _collect(display_tags)

                    # Also consider top-level flattened tags payload if provided (Hydrus API sometimes includes it)
                    top_level_tags = meta.get("tags_flat", []) or meta.get("tags", [])
                    _collect(top_level_tags)

                # Prefer Hydrus-provided extension (e.g. ".webm"); fall back to MIME map.
                mime_type = meta.get("mime")
                ext = str(meta.get("ext") or "").strip().lstrip(".")
                if not ext and mime_type:
                    for category in mime_maps.values():
                        for _ext_key, info in category.items():
                            if mime_type in info.get("mimes", []):
                                ext = str(info.get("ext", "")).strip().lstrip(".")
                                break
                        if ext:
                            break

                # Filter results based on query type
                # If user provided explicit namespace (has ':'), don't do substring filtering
                # Just include what the tag search returned
                has_namespace = ":" in query_lower

                if has_namespace:
                    # Explicit namespace search - already filtered by Hydrus tag search
                    # Include this result as-is
                    file_url = f"{self.URL.rstrip('/')}/get_files/file?hash={hash_hex}"
                    results.append(
                        {
                            "hash": hash_hex,
                            "url": file_url,
                            "name": title,
                            "title": title,
                            "size": size,
                            "size_bytes": size,
                            "store": self.NAME,
                            "tag": all_tags,
                            "file_id": file_id,
                            "mime": mime_type,
                            "ext": ext,
                        }
                    )
                else:
                    # Free-form search: check if search terms match title or FREEFORM tags.
                    # Do NOT implicitly match other namespace tags (except title:).
                    freeform_tags = [
                        t for t in all_tags
                        if isinstance(t, str) and t and (":" not in t)
                    ]
                    searchable_text = (title + " " + " ".join(freeform_tags)).lower()

                    match = True
                    if query_lower != "*" and search_terms:
                        for term in search_terms:
                            if term not in searchable_text:
                                match = False
                                break

                    if match:
                        file_url = f"{self.URL.rstrip('/')}/get_files/file?hash={hash_hex}"
                        results.append(
                            {
                                "hash": hash_hex,
                                "url": file_url,
                                "name": title,
                                "title": title,
                                "size": size,
                                "size_bytes": size,
                                "store": self.NAME,
                                "tag": all_tags,
                                "file_id": file_id,
                                "mime": mime_type,
                                "ext": ext,
                            }
                        )

            debug(f"{prefix} {len(results)} result(s)")
            if ext_filter:
                wanted = ext_filter
                filtered: list[dict[str, Any]] = []
                for item in results:
                    try:
                        if _normalize_ext_filter(str(item.get("ext") or "")) == wanted:
                            filtered.append(item)
                    except Exception:
                        continue
                results = filtered

            return results[:limit]

        except Exception as exc:
            log(f"❌ Hydrus search failed: {exc}", file=sys.stderr)
            import traceback

            traceback.print_exc(file=sys.stderr)
            raise

    def get_file(self, file_hash: str, **kwargs: Any) -> Path | str | None:
        """Return a browser URL for the file.

        IMPORTANT: this method must be side-effect free (do not auto-open a browser).
        Only explicit user actions (e.g. the get-file cmdlet) should open files.
        """

        debug(f"{self._log_prefix()} get_file: start hash={file_hash[:12]}...")

        # Build browser URL with access key
        base_url = str(self.URL).rstrip("/")
        access_key = str(self.API)
        browser_url = (
            f"{base_url}/get_files/file?hash={file_hash}&Hydrus-Client-API-Access-Key={access_key}"
        )
        debug(f"{self._log_prefix()} get_file: url={browser_url}")
        return browser_url

    def delete_file(self, file_identifier: str, **kwargs: Any) -> bool:
        """Delete a file from Hydrus, then clear the deletion record.

        This is used by the delete-file cmdlet when the item belongs to a HydrusNetwork store.
        """
        try:
            client = self._client
            if client is None:
                debug(f"{self._log_prefix()} delete_file: client unavailable")
                return False

            file_hash = str(file_identifier or "").strip().lower()
            if len(file_hash) != 64 or not all(ch in "0123456789abcdef"
                                               for ch in file_hash):
                debug(
                    f"{self._log_prefix()} delete_file: invalid file hash '{file_identifier}'"
                )
                return False

            reason = kwargs.get("reason")
            reason_text = (
                str(reason).strip() if isinstance(reason,
                                                  str) and reason.strip() else None
            )

            # 1) Delete file
            client.delete_files([file_hash], reason=reason_text)

            # 2) Clear deletion record (best-effort)
            try:
                client.clear_file_deletion_record([file_hash])
            except Exception as exc:
                debug(
                    f"{self._log_prefix()} delete_file: clear_file_deletion_record failed: {exc}"
                )

            return True
        except Exception as exc:
            debug(f"{self._log_prefix()} delete_file failed: {exc}")
            return False

    def get_metadata(self, file_hash: str, **kwargs: Any) -> Optional[Dict[str, Any]]:
        """Get metadata for a file from Hydrus by hash.

        Args:
            file_hash: SHA256 hash of the file (64-char hex string)

        Returns:
            Dict with metadata fields or None if not found
        """
        try:
            client = self._client
            if not client:
                debug(f"{self._log_prefix()} get_metadata: client unavailable")
                return None

            # Fetch file metadata with the fields we need for CLI display.
            payload = client.fetch_file_metadata(
                hashes=[file_hash],
                include_service_keys_to_tags=True,
                include_file_url=True,
                include_duration=True,
                include_size=True,
                include_mime=True,
            )

            if not payload or not payload.get("metadata"):
                return None

            meta = payload["metadata"][0]

            # Hydrus can return placeholder metadata rows for unknown hashes.
            if not isinstance(meta, dict) or meta.get("file_id") is None:
                return None

            # Extract title from tags
            title = f"Hydrus_{file_hash[:12]}"
            tags_payload = meta.get("tags",
                                    {})
            if isinstance(tags_payload, dict):
                for service_data in tags_payload.values():
                    if isinstance(service_data, dict):
                        display_tags = service_data.get("display_tags",
                                                        {})
                        if isinstance(display_tags, dict):
                            current_tags = display_tags.get("0", [])
                            if isinstance(current_tags, list):
                                for tag in current_tags:
                                    if str(tag).lower().startswith("title:"):
                                        title = tag.split(":", 1)[1].strip()
                                        break
                    if title != f"Hydrus_{file_hash[:12]}":
                        break

            # Hydrus may return mime as an int enum, or sometimes a human label.
            mime_val = meta.get("mime")
            filetype_human = (
                meta.get("filetype_human") or meta.get("mime_human")
                or meta.get("mime_string")
            )

            # Determine ext: prefer Hydrus metadata ext, then filetype_human (when it looks like an ext),
            # then title suffix, then file path suffix.
            ext = str(meta.get("ext") or "").strip().lstrip(".")
            if not ext:
                ft = str(filetype_human or "").strip().lstrip(".").lower()
                if ft and ft != "unknown filetype" and ft.isalnum() and len(ft) <= 8:
                    # Treat simple labels like "mp4", "m4a", "webm" as extensions.
                    ext = ft
            if not ext and isinstance(title, str) and "." in title:
                try:
                    ext = Path(title).suffix.lstrip(".")
                except Exception:
                    ext = ""
            if not ext:
                try:
                    path_payload = client.get_file_path(file_hash)
                    if isinstance(path_payload, dict):
                        p = path_payload.get("path")
                        if isinstance(p, str) and p.strip():
                            ext = Path(p.strip()).suffix.lstrip(".")
                except Exception:
                    ext = ""

            # If extension is still unknown, attempt a best-effort lookup from MIME.
            def _mime_from_ext(ext_value: str) -> str:
                ext_clean = str(ext_value or "").strip().lstrip(".").lower()
                if not ext_clean:
                    return ""
                try:
                    for category in mime_maps.values():
                        info = category.get(ext_clean)
                        if isinstance(info, dict):
                            mimes = info.get("mimes")
                            if isinstance(mimes, list) and mimes:
                                first = mimes[0]
                                return str(first)
                except Exception:
                    return ""
                return ""

            # Normalize to a MIME string for CLI output.
            # Avoid passing through human labels like "unknown filetype".
            mime_type = ""
            if isinstance(mime_val, str):
                candidate = mime_val.strip()
                if "/" in candidate and candidate.lower() != "unknown filetype":
                    mime_type = candidate
            if not mime_type and isinstance(filetype_human, str):
                candidate = filetype_human.strip()
                if "/" in candidate and candidate.lower() != "unknown filetype":
                    mime_type = candidate
            if not mime_type:
                mime_type = _mime_from_ext(ext)

            # Normalize size/duration to stable scalar types.
            size_val = meta.get("size")
            if size_val is None:
                size_val = meta.get("size_bytes")
            try:
                size_int: int | None = int(size_val) if size_val is not None else None
            except Exception:
                size_int = None

            dur_val = meta.get("duration")
            if dur_val is None:
                dur_val = meta.get("duration_ms")
            try:
                dur_int: int | None = int(dur_val) if dur_val is not None else None
            except Exception:
                dur_int = None

            raw_urls = meta.get("known_urls") or meta.get("urls") or meta.get("url"
                                                                              ) or []
            url_list: list[str] = []
            if isinstance(raw_urls, str):
                s = raw_urls.strip()
                url_list = [s] if s else []
            elif isinstance(raw_urls, list):
                url_list = [
                    str(u).strip() for u in raw_urls
                    if isinstance(u, str) and str(u).strip()
                ]

            return {
                "hash": file_hash,
                "title": title,
                "ext": ext,
                "size": size_int,
                "mime": mime_type,
                # Keep raw fields available for troubleshooting/other callers.
                "hydrus_mime": mime_val,
                "filetype_human": filetype_human,
                "duration_ms": dur_int,
                "url": url_list,
            }

        except Exception as exc:
            debug(f"{self._log_prefix()} get_metadata failed: {exc}")
            return None

    def get_tag(self, file_identifier: str, **kwargs: Any) -> Tuple[List[str], str]:
        """Get tags for a file from Hydrus by hash.

        Args:
            file_identifier: File hash (SHA256 hex string)
            **kwargs: Optional service_name parameter

        Returns:
            Tuple of (tags_list, source_description)
            where source is always "hydrus"
        """
        try:
            from API import HydrusNetwork as hydrus_wrapper

            file_hash = str(file_identifier or "").strip().lower()
            if len(file_hash) != 64 or not all(ch in "0123456789abcdef"
                                               for ch in file_hash):
                debug(
                    f"{self._log_prefix()} get_tags: invalid file hash '{file_identifier}'"
                )
                return [], "unknown"

            # Get Hydrus client and service info
            client = self._client
            if not client:
                debug(f"{self._log_prefix()} get_tags: client unavailable")
                return [], "unknown"

            # Fetch file metadata
            payload = client.fetch_file_metadata(
                hashes=[file_hash],
                include_service_keys_to_tags=True,
                include_file_url=False
            )

            items = payload.get("metadata") if isinstance(payload, dict) else None
            if not isinstance(items, list) or not items:
                debug(
                    f"{self._log_prefix()} get_tags: no metadata for hash {file_hash}"
                )
                return [], "unknown"

            meta = items[0] if isinstance(items[0], dict) else None
            if not isinstance(meta, dict) or meta.get("file_id") is None:
                debug(
                    f"{self._log_prefix()} get_tags: invalid metadata for hash {file_hash}"
                )
                return [], "unknown"

            # Extract tags using service name
            service_name = "my tags"
            service_key = hydrus_wrapper.get_tag_service_key(client, service_name)

            # Extract tags from metadata
            tags = self._extract_tags_from_hydrus_meta(meta, service_key, service_name)

            return [
                str(t).strip().lower() for t in tags if isinstance(t, str) and t.strip()
            ], "hydrus"

        except Exception as exc:
            debug(f"{self._log_prefix()} get_tags failed: {exc}")
            return [], "unknown"

    def add_tag(self, file_identifier: str, tags: List[str], **kwargs: Any) -> bool:
        """Add tags to a Hydrus file."""
        try:
            client = self._client
            if client is None:
                debug(f"{self._log_prefix()} add_tag: client unavailable")
                return False

            file_hash = str(file_identifier or "").strip().lower()
            if len(file_hash) != 64 or not all(ch in "0123456789abcdef"
                                               for ch in file_hash):
                debug(
                    f"{self._log_prefix()} add_tag: invalid file hash '{file_identifier}'"
                )
                return False
            service_name = kwargs.get("service_name") or "my tags"

            incoming_tags = [
                str(t).strip().lower() for t in (tags or [])
                if isinstance(t, str) and str(t).strip()
            ]
            if not incoming_tags:
                return True

            try:
                existing_tags, _src = self.get_tag(file_hash)
            except Exception:
                existing_tags = []

            from metadata import compute_namespaced_tag_overwrite

            tags_to_remove, tags_to_add, _merged = compute_namespaced_tag_overwrite(
                existing_tags, incoming_tags
            )

            if not tags_to_add and not tags_to_remove:
                return True

            did_any = False
            if tags_to_remove:
                try:
                    client.delete_tag(file_hash, tags_to_remove, service_name)
                    did_any = True
                except Exception as exc:
                    debug(f"{self._log_prefix()} add_tag: delete_tag failed: {exc}")
            if tags_to_add:
                try:
                    client.add_tag(file_hash, tags_to_add, service_name)
                    did_any = True
                except Exception as exc:
                    debug(f"{self._log_prefix()} add_tag: add_tag failed: {exc}")

            return did_any
        except Exception as exc:
            debug(f"{self._log_prefix()} add_tag failed: {exc}")
            return False

    def delete_tag(self, file_identifier: str, tags: List[str], **kwargs: Any) -> bool:
        """Delete tags from a Hydrus file."""
        try:
            client = self._client
            if client is None:
                debug(f"{self._log_prefix()} delete_tag: client unavailable")
                return False

            file_hash = str(file_identifier or "").strip().lower()
            if len(file_hash) != 64 or not all(ch in "0123456789abcdef"
                                               for ch in file_hash):
                debug(
                    f"{self._log_prefix()} delete_tag: invalid file hash '{file_identifier}'"
                )
                return False
            service_name = kwargs.get("service_name") or "my tags"
            raw_list = list(tags) if isinstance(tags, (list, tuple)) else [str(tags)]
            tag_list = [
                str(t).strip().lower() for t in raw_list
                if isinstance(t, str) and str(t).strip()
            ]
            if not tag_list:
                return False
            client.delete_tag(file_hash, tag_list, service_name)
            return True
        except Exception as exc:
            debug(f"{self._log_prefix()} delete_tag failed: {exc}")
            return False

    def get_url(self, file_identifier: str, **kwargs: Any) -> List[str]:
        """Get known url for a Hydrus file."""
        try:
            client = self._client

            file_hash = str(file_identifier or "").strip().lower()
            if len(file_hash) != 64 or not all(ch in "0123456789abcdef"
                                               for ch in file_hash):
                return []

            payload = client.fetch_file_metadata(
                hashes=[file_hash],
                include_file_url=False
            )
            items = payload.get("metadata") if isinstance(payload, dict) else None
            if not isinstance(items, list) or not items:
                return []
            meta = items[0] if isinstance(items[0],
                                          dict) else {}

            raw_urls: Any = meta.get("known_urls"
                                     ) or meta.get("urls") or meta.get("url") or []
            if isinstance(raw_urls, str):
                val = raw_urls.strip()
                return [val] if val else []
            if isinstance(raw_urls, list):
                out: list[str] = []
                for u in raw_urls:
                    if not isinstance(u, str):
                        continue
                    u = u.strip()
                    if u:
                        out.append(u)
                return out
            return []
        except Exception as exc:
            debug(f"{self._log_prefix()} get_url failed: {exc}")
            return []

    def add_url(self, file_identifier: str, url: List[str], **kwargs: Any) -> bool:
        """Associate one or more url with a Hydrus file."""
        try:
            client = self._client
            if client is None:
                debug(f"{self._log_prefix()} add_url: client unavailable")
                return False
            for u in url:
                client.associate_url(file_identifier, u)
            return True
        except Exception as exc:
            debug(f"{self._log_prefix()} add_url failed: {exc}")
            return False

    def add_url_bulk(self, items: List[tuple[str, List[str]]], **kwargs: Any) -> bool:
        """Bulk associate urls with Hydrus files.

        This is a best-effort convenience wrapper used by cmdlets to batch url associations.
        Hydrus' client API is still called per (hash,url) pair, but this consolidates the
        cmdlet-level control flow so url association can be deferred until the end.
        """
        try:
            client = self._client
            if client is None:
                debug(f"{self._log_prefix()} add_url_bulk: client unavailable")
                return False

            any_success = False
            for file_identifier, urls in items or []:
                h = str(file_identifier or "").strip().lower()
                if len(h) != 64:
                    continue
                for u in urls or []:
                    s = str(u or "").strip()
                    if not s:
                        continue
                    try:
                        client.associate_url(h, s)
                        any_success = True
                    except Exception:
                        continue
            return any_success
        except Exception as exc:
            debug(f"{self._log_prefix()} add_url_bulk failed: {exc}")
            return False

    def delete_url(self, file_identifier: str, url: List[str], **kwargs: Any) -> bool:
        """Delete one or more url from a Hydrus file."""
        try:
            client = self._client
            if client is None:
                debug(f"{self._log_prefix()} delete_url: client unavailable")
                return False
            for u in url:
                client.delete_url(file_identifier, u)
            return True
        except Exception as exc:
            debug(f"{self._log_prefix()} delete_url failed: {exc}")
            return False

    def get_note(self, file_identifier: str, **kwargs: Any) -> Dict[str, str]:
        """Get notes for a Hydrus file (default note service only)."""
        try:
            client = self._client
            if client is None:
                debug(f"{self._log_prefix()} get_note: client unavailable")
                return {}

            file_hash = str(file_identifier or "").strip().lower()
            if len(file_hash) != 64 or not all(ch in "0123456789abcdef"
                                               for ch in file_hash):
                return {}

            payload = client.fetch_file_metadata(hashes=[file_hash], include_notes=True)
            items = payload.get("metadata") if isinstance(payload, dict) else None
            if not isinstance(items, list) or not items:
                return {}
            meta = items[0] if isinstance(items[0], dict) else None
            if not isinstance(meta, dict):
                return {}

            notes_payload = meta.get("notes")
            if isinstance(notes_payload, dict):
                return {
                    str(k): str(v or "")
                    for k, v in notes_payload.items() if str(k).strip()
                }

            return {}
        except Exception as exc:
            debug(f"{self._log_prefix()} get_note failed: {exc}")
            return {}

    def set_note(
        self,
        file_identifier: str,
        name: str,
        text: str,
        **kwargs: Any
    ) -> bool:
        """Set a named note for a Hydrus file (default note service only)."""
        try:
            client = self._client
            if client is None:
                debug(f"{self._log_prefix()} set_note: client unavailable")
                return False

            file_hash = str(file_identifier or "").strip().lower()
            if len(file_hash) != 64 or not all(ch in "0123456789abcdef"
                                               for ch in file_hash):
                return False

            note_name = str(name or "").strip()
            if not note_name:
                return False
            note_text = str(text or "")

            client.set_notes(file_hash,
                             {
                                 note_name: note_text
                             })
            return True
        except Exception as exc:
            debug(f"{self._log_prefix()} set_note failed: {exc}")
            return False

    def delete_note(self, file_identifier: str, name: str, **kwargs: Any) -> bool:
        """Delete a named note for a Hydrus file (default note service only)."""
        try:
            client = self._client
            if client is None:
                debug(f"{self._log_prefix()} delete_note: client unavailable")
                return False

            file_hash = str(file_identifier or "").strip().lower()
            if len(file_hash) != 64 or not all(ch in "0123456789abcdef"
                                               for ch in file_hash):
                return False

            note_name = str(name or "").strip()
            if not note_name:
                return False

            client.delete_notes(file_hash, [note_name])
            return True
        except Exception as exc:
            debug(f"{self._log_prefix()} delete_note failed: {exc}")
            return False

    @staticmethod
    def _extract_tags_from_hydrus_meta(
        meta: Dict[str,
                   Any],
        service_key: Optional[str],
        service_name: str
    ) -> List[str]:
        """Extract current tags from Hydrus metadata dict.

        Prefers display_tags (includes siblings/parents, excludes deleted).
        Falls back to storage_tags status '0' (current).
        """
        tags_payload = meta.get("tags")
        if not isinstance(tags_payload, dict):
            return []

        svc_data = None
        if service_key:
            svc_data = tags_payload.get(service_key)
        if not isinstance(svc_data, dict):
            return []

        # Prefer display_tags (Hydrus computes siblings/parents)
        display = svc_data.get("display_tags")
        if isinstance(display, list) and display:
            return [
                str(t) for t in display
                if isinstance(t, (str, bytes)) and str(t).strip()
            ]

        # Fallback to storage_tags status '0' (current)
        storage = svc_data.get("storage_tags")
        if isinstance(storage, dict):
            current_list = storage.get("0") or storage.get(0)
            if isinstance(current_list, list):
                return [
                    str(t) for t in current_list
                    if isinstance(t, (str, bytes)) and str(t).strip()
                ]

        return []