function Searxng(matrixClient) {
	this.matrixClient = matrixClient;
	this.uploadMatrixClient = matrixClient;
	this.blacklistedImgRooms = [];
	this.blacklistedUimgRooms = [];
	this.cooldownImmuneUsers = [];
	this.roomCooldowns = new Map();
	this.roomUserWhitelists = new Map();
	this.searxngInstance = "";
	this.searxngParameters = "enabled_engines=duckduckgo images__images,google images__images,bing images__images&disabled_engines=flickr__images,nyaa__images,qwant images__images,artic__images,deviantart__images,library of congress__images,unsplash__images,openverse__images"
}

Searxng.prototype.setUploadMatrixClient = function(uploadMatrixClient){ this.uploadMatrixClient = uploadMatrixClient; };
Searxng.prototype.setBlacklistedImgRooms = function(blacklistedImgRooms){ this.blacklistedImgRooms = blacklistedImgRooms; };
Searxng.prototype.setBlacklistedUimgRooms = function(blacklistedUimgRooms){ this.blacklistedUimgRooms = blacklistedUimgRooms; };
Searxng.prototype.setCooldownImmuneUsers = function(cooldownImmuneUsers){ this.cooldownImmuneUsers = cooldownImmuneUsers; };
Searxng.prototype.setRoomCooldowns = function(roomCooldowns){ this.roomCooldowns = roomCooldowns; };
Searxng.prototype.setRoomUserWhitelists = function(roomUserWhitelists){ this.roomUserWhitelists = roomUserWhitelists; };
Searxng.prototype.setSearxngInstance = function(searxngInstance){ this.searxngInstance = searxngInstance; };
Searxng.prototype.setSearxngParameters = function(searxngParameters){ this.searxngParameters = searxngParameters; };

const axios = require('axios');
const request = require('request');

const lastCooldownTimes = new Map();
const lastWarningTimes = new Map();

const imageSearchCmd = "!img"
const unsafeImageSearchCmd = "!uimg"

const searxngCommands = [
  imageSearchCmd,
  unsafeImageSearchCmd
];

function sendImage(results, resultIndex, roomId, name, searchCommand, retryCount, matrixClient, uploadMatrixClient) {

	const resultObj = results[resultIndex]
	var imageURL;
	if (typeof resultObj === 'undefined' || resultObj == null || typeof resultObj.img_src === 'undefined' || resultObj.img_src == null || resultObj.img_src === '') {
		imageURL = "";
	}
	else  {
		imageURL = resultObj.img_src;
		if (imageURL.startsWith("//")) {
			imageURL = "https:" + imageURL;
		}
	}

	(async () => {
		try {
			const imageResponse = await axios.get(imageURL, { responseType: 'arraybuffer' });
			var imageType = imageResponse.headers['content-type'];
			console.debug("[Search text: "+searchCommand+"], "+"[imageURL: "+imageURL+"], "+"[retryCount: "+retryCount+"]"+", [Engine: "+resultObj.engines[0]+"]"+", [content-type: "+imageType+"]");
	 		const uploadResponse = await uploadMatrixClient.uploadContent(imageResponse.data, { rawResponse: false, type: imageType });
	 		const matrixUrl = uploadResponse.content_uri;
			switch(imageType) {
			case "image/jpeg":
			case "image/jpg":
				name = name + ".jpg";
				break;
			case "image/png":
				name = name + ".png";
				break;
			case "image/gif":
				name = name + ".gif";
				break;
			case "application/octet-stream":
				const urlImageType = imageURL.substring(imageURL.lastIndexOf("."));

				switch(urlImageType) {
					case ".jpg":
					case ".jpeg":
						imageType = "image/jpg";
						name = name + ".jpg";
						break;
					case ".png":
						imageType = "image/png";
						name = name + ".png";
						break;
					case ".gif":
						imageType = "image/gif";
						name = name + ".gif";
						break;
				}

				break;
			}
	 		matrixClient.sendImageMessage(roomId, matrixUrl, {"mimetype": imageType}, name, null);
			matrixClient.sendTyping(roomId, false, 3000);
	 	} catch (error) {
				retryCount = retryCount + 1;
				resultIndex = resultIndex + 1;

				if (retryCount > 3 || resultIndex > (results.length - 1)) {
					matrixClient.sendNotice(roomId, "Error occurred during \"" + searchCommand + "\"");
					console.error("ERROR! [Search text: "+searchCommand+"], "+"[imageURL: "+imageURL+"], "+"[retryCount: "+retryCount+"]"+", [Engine: "+resultObj.engines[0]+"]");
					console.error(error);
				}
				else {
					console.warn("Trying next result for '"+searchCommand+"'");
					console.error(error);
					sendImage(results, resultIndex, roomId, name, searchCommand, retryCount, matrixClient, uploadMatrixClient);
				}
		}
	})();
}

Searxng.prototype.handleMessage = function(event, room) {

	const messagePieces = event.getContent().body.split(" ");

	if (searxngCommands.indexOf(messagePieces[0]) > -1) {

		var cooldown = false;

		if (this.blacklistedImgRooms.indexOf(room.roomId) >=0) {
			this.matrixClient.sendNotice(room.roomId, "Image searching has been disabled in this room.");
			return;
		}
		else if (this.blacklistedUimgRooms.indexOf(room.roomId) >=0 && messagePieces[0] == unsafeImageSearchCmd) {
			this.matrixClient.sendNotice(room.roomId, "Image searching without safesearch is disabled in this room.");
			return;
		}
		else if (!room.currentState.maySendMessage(this.matrixClient.getUserId())) {
			console.warn("Don't have permission to post in room "+room.roomId);
			return;
		}
		else if (this.roomUserWhitelists.has(room.roomId) && this.roomUserWhitelists.get(room.roomId).indexOf(event.getSender()) < 0) {
			this.matrixClient.sendNotice(room.roomId, "You are not on the whitelist for this room.");
			return;
		}
		else if (this.cooldownImmuneUsers.indexOf(event.getSender()) < 0) {
			const roomCooldown = this.roomCooldowns.get(room.roomId);

			if (roomCooldown != undefined) {

				const currentTime = Date.now();
				const lastRoomCooldownTime = lastCooldownTimes.get(room.roomId);
				if (lastRoomCooldownTime != undefined) {
					const timeSinceLastCooldown = currentTime - lastRoomCooldownTime;

					if (!isNaN(timeSinceLastCooldown) && (currentTime - lastRoomCooldownTime) < roomCooldown) {

						const lastRoomWarningTime = lastWarningTimes.get(room.roomId);

						if  (isNaN(lastRoomWarningTime) || lastRoomWarningTime != lastRoomCooldownTime) {
							this.matrixClient.sendNotice(room.roomId, "This room has a mandatory cooldown between image commands. Try again later.");
							lastWarningTimes.set(room.roomId, lastRoomCooldownTime);
						}
						return;
					}
				}
				lastCooldownTimes.set(room.roomId, currentTime);
				cooldown = true;
			}
		}

		try {

			var toSearch;
			var resultIndex = 0;

			if (messagePieces.length <= 1) {
				this.matrixClient.sendNotice(room.roomId, "No search terms provided");
				return;
			}
			else if (messagePieces.length == 2) {
				toSearch = messagePieces[1].trim();
			}
			else {
				if (isNaN(messagePieces[1])) {
					toSearch = event.getContent().body.substr(messagePieces[0].length+1);
				}
				else {
					resultIndex = Number(messagePieces[1]) - 1;

					if (resultIndex < 0) {
						this.matrixClient.sendNotice(room.roomId, "Invalid result index given.");
						return;
					}

					toSearch = event.getContent().body.substr(messagePieces[0].length+messagePieces[1].length+2);
				}
			}


			const searchURL = this.searxngInstance + "/search?category_images=1&pageno=1&time_range=&format=json&"+this.searxngParameters+"&safesearch="+(messagePieces[0] == unsafeImageSearchCmd ? "0" : "1")+"&q=" + toSearch;
			this.matrixClient.sendTyping(room.roomId, true, 3000);
			const matrixClient = this.matrixClient;
			const uploadMatrixClient = this.uploadMatrixClient;
			request(searchURL, function (error, response, body) {
				try {
					if (error == null || error == "") {
						const bodyObj = JSON.parse(body);
						const results = bodyObj.results;

						if (typeof results === 'undefined' || results == null || results.length <= 0) {
							matrixClient.sendNotice(room.roomId, "No results found for \""+toSearch+"\"");
							return;
						}
						else if (resultIndex > (results.length - 1))  {
							matrixClient.sendNotice(room.roomId, "No result found for \""+toSearch+"\" at position "+(resultIndex+1));
							return;
						}

						sendImage(results, resultIndex, room.roomId, toSearch, event.getContent().body, 0, matrixClient, uploadMatrixClient);
					}
					else {
						matrixClient.sendNotice(room.roomId, "Error occurred during \"" + event.getContent().body + "\"");
						console.error(error);
					}
				} catch (error) {
			    		matrixClient.sendNotice(room.roomId, "Error occurred during \"" + event.getContent().body + "\"");
			    		console.error(error);
				}

				if (cooldown) {
					lastCooldownTimes.set(room.roomId, Date.now());
				}
			});


		} catch (error) {
		    this.matrixClient.sendNotice(room.roomId, "Error occurred during \"" + event.getContent().body + "\"");
		    console.error(error);
		}
	}

};

Searxng.prototype.startUploadMatrixClient = function() {
	(async () => {
		this.uploadMatrixClient.startClient({initialSyncLimit: 1});
	})();
}

Searxng.prototype.getFormattedHelp = function() {
	return "\
		<code>!img [image_search_text]</code> - Return top result for image<br />\
		       <code>!img [n] [image_search_text]</code> - Return nth result for image. [n] must be a positive number (example: <code>!img 3 cat memes</code>)<br />\
		       <code>!uimg</code> - Same as !img but without safesearch";

}

Searxng.prototype.getHelp = function() {
	return "!img [image_search_text]\" - Return top result for image\r\n\
	     \"!img [n] [image_search_text]\" - Return nth result for image. [n] must be a positive number (example: '!img 3 cat memes')\r\n\
	     \"!uimg\" - Same as !img but without safesearch";

}

module.exports = Searxng;