const cheerio = require("cheerio");
const compressjs = require("compressjs");
const Promise = require("bluebird");
const request = require("request-promise").defaults({
	gzip: true,
	headers: {
		'User-Agent': process.env.fmUserAgent
	}
});
const zlib = require("zlib");

const elevation = require("./elevation");
const utils = require("./utils");

const nameFinderUrl = "https://nominatim.openstreetmap.org";
const limit = 25;
const stateAbbr = {
	"us" : {
		"alabama":"AL","alaska":"AK","arizona":"AZ","arkansas":"AR","california":"CA","colorado":"CO","connecticut":"CT",
		"delaware":"DE","florida":"FL","georgia":"GA","hawaii":"HI","idaho":"ID","illinois":"IL","indiana":"IN","iowa":"IA",
		"kansas":"KS","kentucky":"KY","louisiana":"LA","maine":"ME","maryland":"MD","massachusetts":"MA","michigan":"MI",
		"minnesota":"MN","mississippi":"MS","missouri":"MO","montana":"MT","nebraska":"NE","nevada":"NV","new hampshire":"NH",
		"new jersey":"NJ","new mexico":"NM","new york":"NY","north carolina":"NC","north dakota":"ND","ohio":"OH","oklahoma":"OK",
		"oregon":"OR","pennsylvania":"PA","rhode island":"RI","south carolina":"SC","south dakota":"SD","tennessee":"TN",
		"texas":"TX","utah":"UT","vermont":"VT","virginia":"VA","washington":"WA","west virginia":"WV","wisconsin":"WI","wyoming":"WY"
	},
	"it" : {
		"agrigento":"AG","alessandria":"AL","ancona":"AN","aosta":"AO","arezzo":"AR","ascoli piceno":"AP","asti":"AT",
		"avellino":"AV","bari":"BA","barletta":"BT","barletta-andria-trani":"BT","belluno":"BL","benevento":"BN",
		"bergamo":"BG","biella":"BI","bologna":"BO","bolzano":"BZ","brescia":"BS","brindisi":"BR","cagliari":"CA",
		"caltanissetta":"CL","campobasso":"CB","carbonia-iglesias":"CI","caserta":"CE","catania":"CT","catanzaro":"CZ",
		"chieti":"CH","como":"CO","cosenza":"CS","cremona":"CR","crotone":"KR","cuneo":"CN","enna":"EN","fermo":"FM",
		"ferrara":"FE","firenze":"FI","foggia":"FG","forli-cesena":"FC","frosinone":"FR","genova":"GE","gorizia":"GO",
		"grosseto":"GR","imperia":"IM","isernia":"IS","la spezia":"SP","l'aquila":"AQ","latina":"LT","lecce":"LE",
		"lecco":"LC","livorno":"LI","lodi":"LO","lucca":"LU","macerata":"MC","mantova":"MN","massa e carrara":"MS",
		"matera":"MT","medio campidano":"VS","messina":"ME","milano":"MI","modena":"MO","monza e brianza":"MB",
		"napoli":"NA","novara":"NO","nuoro":"NU","ogliastra":"OG","olbia-tempio":"OT","oristano":"OR","padova":"PD",
		"palermo":"PA","parma":"PR","pavia":"PV","perugia":"PG","pesaro e urbino":"PU","pescara":"PE","piacenza":"PC",
		"pisa":"PI","pistoia":"PT","pordenone":"PN","potenza":"PZ","prato":"PO","ragusa":"RG","ravenna":"RA",
		"reggio calabria":"RC","reggio emilia":"RE","rieti":"RI","rimini":"RN","roma":"RM","rovigo":"RO","salerno":"SA",
		"sassari":"SS","savona":"SV","siena":"SI","siracusa":"SR","sondrio":"SO","taranto":"TA","teramo":"TE","terni":"TR",
		"torino":"TO","trapani":"TP","trento":"TN","treviso":"TV","trieste":"TS","udine":"UD","varese":"VA","venezia":"VE",
		"verbano":"VB","verbano-cusio-ossola":"VB","vercelli":"VC","verona":"VR","vibo valentia":"VV","vicenza":"VI","viterbo":"VT"
	},
	"ca" : {
		"ontario":"ON","quebec":"QC","nova scotia":"NS","new brunswick":"NB","manitoba":"MB","british columbia":"BC",
		"prince edward island":"PE","saskatchewan":"SK","alberta":"AB","newfoundland and labrador":"NL"
	},
	"au" : {
		"australian capital territory":"ACT","jervis bay territory":"JBT","new south wales":"NSW","northern territory":"NT",
		"queensland":"QLD","south australia":"SA","tasmania":"TAS","victoria":"VIC","western australia":"WA"
	}
};


const search = module.exports = {

	find(query, loadUrls, loadElevation) {
		return Promise.resolve().then(function() {
			query = query.replace(/^\s+/, "").replace(/\s+$/, "");

			if(loadUrls) {
				let m = query.match(/^(node|way|relation)\s+(\d+)$/);
				if(m)
					return search._loadUrl("https://api.openstreetmap.org/api/0.6/" + m[1] + "/" + m[2] + (m[1] != "node" ? "/full" : ""), true);

				m = query.match(/^trace\s+(\d+)$/);
				if(m)
					return search._loadUrl("https://www.openstreetmap.org/trace/" + m[1] + "/data");

				if(query.match(/^https?:\/\//))
					return search._loadUrl(query);
			}

			let lonlat_match = query.match(/^(geo\s*:\s*)?(-?\s*\d+([.,]\d+)?)\s*[,;]\s*(-?\s*\d+([.,]\d+)?)(\s*\?z\s*=\s*(\d+))?$/);
			if(lonlat_match) {
				return search._findLonLat({
					lat: 1*lonlat_match[2].replace(",", ".").replace(/\s+/, ""),
					lon : 1*lonlat_match[4].replace(",", ".").replace(/\s+/, ""),
					zoom : lonlat_match[7] != null ? 1*lonlat_match[7] : null
				}, loadElevation).then((res) => (res.map((res) => (Object.assign(res, {id: query})))));
			}

			let osm_match = query.match(/^([nwr])(\d+)$/i);
			if(osm_match)
				return search._findOsmObject(osm_match[1], osm_match[2], loadElevation);

			return search._findQuery(query, loadElevation);
		});
	},

	_findQuery(query, loadElevation) {
		return request({
			url: nameFinderUrl + "/search?format=jsonv2&polygon_geojson=1&addressdetails=1&namedetails=1&limit=" + encodeURIComponent(limit) + "&extratags=1&q=" + encodeURIComponent(query),
			json: true
		}).then(function(body) {
			if(!body)
				throw "Invalid response from name finder.";

			if(body.error)
				throw body.error;

			let points = body.filter((res) => (res.lon && res.lat));
			if(loadElevation && points.length > 0) {
				return elevation.getElevationForPoints(points).then((elevations) => {
					elevations.forEach((elevation, i) => {
						points[i].elevation = elevation;
					});

					return body;
				});
			} else
				return body;
		}).then((body) => (body.map(search._prepareSearchResult)));
	},

	_findOsmObject(type, id, loadElevation) {
		return request({
			url: `${nameFinderUrl}/reverse?format=json&addressdetails=1&polygon_geojson=1&extratags=1&namedetails=1&osm_type=${encodeURI(type.toUpperCase())}&osm_id=${encodeURI(id)}`,
			json: true
		}).then(function(body) {
			if(!body || body.error) {
				throw body ? body.error : "Invalid response from name finder";
			}

			if(loadElevation && body.lat && body.lon)
				return elevation.getElevationForPoint(body).then((elevation) => (Object.assign(body, { elevation })));
			else
				return body;
		}).then((body) => ([ search._prepareSearchResult(body) ]));
	},

	_findLonLat(lonlatWithZoom, loadElevation) {
		return Promise.all([
			request({
				url: `${nameFinderUrl}/reverse?format=json&addressdetails=1&polygon_geojson=1&extratags=1&namedetails=1&lat=${encodeURI(lonlatWithZoom.lat)}&lon=${encodeURI(lonlatWithZoom.lon)}&zoom=${encodeURI(lonlatWithZoom.zoom != null ? (lonlatWithZoom.zoom >= 12 ? lonlatWithZoom.zoom+2 : lonlatWithZoom.zoom) : 17)}`,
				json: true
			}),
			...(loadElevation ? [elevation.getElevationForPoint(lonlatWithZoom)] : [])
		]).then(function([body, elevation]) {
			if(!body || body.error) {
				let name = utils.round(lonlatWithZoom.lat, 5) + ", " + utils.round(lonlatWithZoom.lon, 5);
				return [ {
					lat: lonlatWithZoom.lat,
					lon : lonlatWithZoom.lon,
					type : "coordinates",
					short_name: name,
					display_name : name,
					zoom: lonlatWithZoom.zoom != null ? lonlatWithZoom.zoom : 15,
					icon: null,
					elevation: elevation
				} ];
			}

			body.lat = lonlatWithZoom.lat;
			body.lon = lonlatWithZoom.lon;

			if(lonlatWithZoom.zoom != null)
				body.zoom = lonlatWithZoom.zoom;

			body.elevation = elevation;

			return [ search._prepareSearchResult(body) ];
		});
	},

	_prepareSearchResult(result) {
		let displayName = search._makeDisplayName(result);
		return {
			short_name: result.namedetails.name || displayName.split(',')[0],
			display_name: displayName,
			boundingbox: result.boundingbox,
			lat: result.lat,
			lon: result.lon,
			zoom: result.zoom,
			extratags: result.extratags,
			geojson: result.geojson,
			icon: result.icon && result.icon.replace(/^.*\/([a-z0-9_]+)\.[a-z0-9]+\.[0-9]+\.[a-z0-9]+$/i, "$1"),
			type: result.type == "yes" ? result.category : result.type,
			id: result.osm_id ? result.osm_type.charAt(0) + result.osm_id : null,
			elevation: result.elevation
		};
	},

	/**
	 * Tries to format a search result in a readable way according to the address notation habits in
	 * the appropriate country.
	 * @param result {Object} A place object as returned by Nominatim
	 * @return {String} A readable name for the search result
	 */
	_makeDisplayName(result) {
		// See http://en.wikipedia.org/wiki/Address_%28geography%29#Mailing_address_format_by_country for
		// address notation guidelines

		let type = result.type;
		let name = result.namedetails.name;
		let countryCode = result.address.country_code;

		let road = result.address.road;
		let housenumber = result.address.house_number;
		let suburb = result.address.town || result.address.suburb || result.address.village || result.address.hamlet || result.address.residential;
		let postcode = result.address.postcode;
		let city = result.address.city;
		let county = result.address.county;
		let state = result.address.state;
		let country = result.address.country;

		if([ "road", "residential", "town", "suburb", "village", "hamlet", "residential", "city", "county", "state" ].indexOf(type) != -1)
			name = "";

		if(!city && suburb)
		{
			city = suburb;
			suburb = "";
		}

		if(road)
		{
			switch(countryCode)
			{
				case "pl":
					road = "ul. "+road;
					break;
				case "ro":
					road = "str. "+road;
					break;
			}
		}

		// Add house number to road
		if(road && housenumber)
		{
			switch(countryCode)
			{
				case "ar":
				case "at":
				case "ca":
				case "de":
				case "hr":
				case "cz":
				case "dk":
				case "fi":
				case "is":
				case "il":
				case "it":
				case "nl":
				case "no":
				case "pe":
				case "pl":
				case "sk":
				case "si":
				case "se":
				case "tr":
					road += " "+housenumber;
					break;
				case "be":
				case "es":
					road += ", "+housenumber;
					break;
				case "cl":
					road += " N° "+housenumber;
					break;
				case "hu":
					road += " "+housenumber+".";
					break;
				case "id":
					road += " No. "+housenumber;
					break;
				case "my":
					road = "No." +housenumber+", "+road;
					break;
				case "ro":
					road += ", nr. "+road;
					break;
				case "au":
				case "fr":
				case "hk":
				case "ie":
				case "in":
				case "nz":
				case "sg":
				case "lk":
				case "tw":
				case "gb":
				case "us":
				default:
					road += housenumber+" "+road;
					break;
			}
		}

		// Add postcode and districts to city
		switch(countryCode)
		{
			case "ar":
				if(postcode && city)
					city = postcode+", "+city;
				else if(postcode)
					city = postcode;
				break;
			case "at":
			case "ch":
			case "de":
				if(city)
				{
					if(suburb)
						city += "-"+(suburb);
					suburb = null;
					if(type == "suburb" || type == "residential")
						type = "city";

					if(postcode)
						city = postcode+" "+city;
				}
				break;
			case "be":
			case "hr":
			case "cz":
			case "dk":
			case "fi":
			case "fr":
			case "hu":
			case "is":
			case "il":
			case "my":
			case "nl":
			case "no":
			case "sk":
			case "si":
			case "es":
			case "se":
			case "tr":
				if(city && postcode)
					city = postcode+" "+city;
				break;
			case "au":
			case "ca":
			case "us":
				if(city && state)
				{
					let thisStateAbbr = stateAbbr[countryCode][state.toLowerCase()];
					if(thisStateAbbr)
					{
						city += " "+thisStateAbbr;
						state = null;
					}
				}
				if(city && postcode)
					city += " "+postcode;
				else if(postcode)
					city = postcode;
				break;
			case "it":
				if(city)
				{
					if(county)
					{
						let countyAbbr = stateAbbr.it[county.toLowerCase().replace(/ì/g, "i")];
						if(countyAbbr)
						{
							city += " ("+countyAbbr+")";
							county = null;
						}
					}
					if(postcode)
						city  = postcode+" "+city;
				}
				break;
			case "ro":
				if(city && county)
				{
					city += ", jud. "+county;
					county = null;
				}
				if(city && postcode)
					city += ", "+postcode;
				break;
			case "cl":
			case "hk":
				// Postcode rarely/not used
			case "ie":
			case "in":
			case "id":
			case "nz":
			case "pe":
			case "sg":
			case "lk":
			case "tw":
			case "gb":
			default:
				if(city && postcode)
					city = city+" "+postcode;
				else if(postcode)
					city = postcode;
				break;
		}

		let ret = [ ];

		if(name)
			ret.push(name);
		if(road)
			ret.push(road);
		if(suburb)
			ret.push(suburb);
		if(city)
			ret.push(city);
		if([ "residential", "town", "suburb", "village", "hamlet", "residential", "city", "county", "state" ].indexOf(type) != -1)
		{ // Searching for a town
			if(county && county != city)
				ret.push(county);
			if(state && state != city)
				ret.push(state);
		}

		if(country)
			ret.push(country);

		return ret.join(", ");
	},

	_loadUrl(url, completeOsmObjects) {
		return request(url, { encoding: null }).then(function(bodyBuf) {
			if(!bodyBuf)
				throw "Invalid response from server.";

			if(bodyBuf[0] == 0x42 && bodyBuf[1] == 0x5a && bodyBuf[2] == 0x68) {// bzip2
				return new Buffer(compressjs.Bzip2.decompressFile(bodyBuf));
			}
			else if(bodyBuf[0] == 0x1f && bodyBuf[1] == 0x8b && bodyBuf[2] == 0x08) // gzip
				return Promise.promisify(zlib.gunzip.bind(zlib))(bodyBuf);
			else
				return bodyBuf;
		}).then(function(bodyBuf) {
			let body = bodyBuf.toString();

			if(url.match(/^https?:\/\/www\.freietonne\.de\/seekarte\/getOpenLayerPois\.php\?/))
				return body;
			else if(body.match(/^\s*</)) {
				let $ = cheerio.load(body, { xmlMode: true });
				let rootEl = $.root().children();

				if(rootEl.is("osm") && completeOsmObjects) {
					return search._loadSubRelations($).then(function() { return $.xml(); });
				} else if(rootEl.is("gpx,kml,osm"))
					return body;
				else
					throw "Unknown file format.";
			} else if(body.match(/^\s*\{/)) {
				let content = JSON.parse(body);
				if(content.type)
					return body;
				else
					throw "Unknown file format.";
			} else {
				throw "Unknown file format.";
			}
		});
	},

	_loadSubRelations($) {
		let ret = [ ];
		$("member[type='relation']").each(function() {
			let relId = $(this).attr("ref");
			if($("relation[id='" + relId + "']").length == 0) {
				ret.push(request("https://api.openstreetmap.org/api/0.6/relation/" + relId + "/full"));
			}
		});

		if(ret.length > 0) {
			return Promise.all(ret).then(function(relations) {
				relations.forEach(function(relation) {
					$.root().children().append(cheerio.load(relation, { xmlMode: true }).root().children().children());
				});

				return search._loadSubRelations($);
			});
		} else {
			return Promise.resolve();
		}
	}

};