package funkin.backend.chart;

import funkin.backend.system.Conductor;
import funkin.backend.chart.ChartData;
import flixel.util.FlxColor;
import haxe.io.Path;
import haxe.Json;

#if sys
import sys.io.File;
import sys.FileSystem;
#end

using StringTools;

class Chart {
	/**
	 * Default background colors for songs without bg color
	 */
	public inline static var defaultColor:FlxColor = 0xFF9271FD;

	public static function loadEventsJson(songName:String) {
		var path = Paths.file('songs/${songName.toLowerCase()}/events.json');
		var data:Array<ChartEvent> = null;
		if (Assets.exists(path)) {
			try {
				data = Json.parse(Assets.getText(path)).events;
			} catch(e) {
				Logs.trace('Failed to load song event data for ${songName} ($path): ${Std.string(e)}', ERROR);
			}
		}
		return data;
	}

	public static function loadChartMeta(songName:String, difficulty:String = "normal", fromMods:Bool = true) {
		var metaPath = Paths.file('songs/${songName.toLowerCase()}/meta.json');
		var metaDiffPath = Paths.file('songs/${songName.toLowerCase()}/meta-${difficulty.toLowerCase()}.json');

		var data:ChartMetaData = null;
		var fromMods:Bool = fromMods;
		for(path in [metaDiffPath, metaPath]) {
			if (Assets.exists(path)) {
				fromMods = Paths.assetsTree.existsSpecific(path, "TEXT", MODS);
				try {
					data = Json.parse(Assets.getText(path));
				} catch(e) {
					Logs.trace('Failed to load song metadata for ${songName} ($path): ${Std.string(e)}', ERROR);
				}
				if (data != null) break;
			}
		}

		if (data == null)
			data = {
				name: songName,
				bpm: 100
			};
		data.setFieldDefault("name", songName);
		data.setFieldDefault("beatsPerMeasure", 4);
		data.setFieldDefault("stepsPerBeat", 4);
		data.setFieldDefault("needsVoices", true);
		data.setFieldDefault("icon", "face");
		data.setFieldDefault("difficulties", []);
		data.setFieldDefault("coopAllowed", false);
		data.setFieldDefault("opponentModeAllowed", false);
		data.setFieldDefault("displayName", data.name);
		data.setFieldDefault("parsedColor", data.color.getColorFromDynamic().getDefault(defaultColor));

		if (data.difficulties.length <= 0) {
			data.difficulties = [for(f in Paths.getFolderContent('songs/${songName.toLowerCase()}/charts/', false, !fromMods)) if (Path.extension(f = f.toUpperCase()) == "JSON") Path.withoutExtension(f)];
			if (data.difficulties.length == 3) {
				var hasHard = false, hasNormal = false, hasEasy = false;
				for(d in data.difficulties) {
					switch(d) {
						case "EASY":	hasEasy = true;
						case "NORMAL":	hasNormal = true;
						case "HARD":	hasHard = true;
					}
				}
				if (hasHard && hasNormal && hasEasy) {
					data.difficulties[0] = "EASY";
					data.difficulties[1] = "NORMAL";
					data.difficulties[2] = "HARD";
				}
			}
		}

		return data;
	}

	public static function parse(songName:String, difficulty:String = "normal"):ChartData {
		var chartPath = Paths.chart(songName, difficulty);
		var base:ChartData = {
			strumLines: [],
			noteTypes: [],
			events: [],
			meta: {
				name: null
			},
			scrollSpeed: 2,
			stage: "stage",
			codenameChart: true,
			fromMods: Paths.assetsTree.existsSpecific(chartPath, "TEXT", MODS)
		};

		var valid:Bool = true;
		if (!Assets.exists(chartPath)) {
			Logs.trace('Chart for song ${songName} ($difficulty) at "$chartPath" was not found.', ERROR, RED);
			valid = false;
		}
		var data:Dynamic = null;
		try {
			if (valid)
				data = Json.parse(Assets.getText(chartPath));
		} catch(e) {
			Logs.trace('Could not parse chart for song ${songName} ($difficulty): ${Std.string(e)}', ERROR, RED);
		}

		if (data != null) {
			/**
			 * CHART CONVERSION
			 */
			#if REGION
			if (Reflect.hasField(data, "codenameChart") && Reflect.field(data, "codenameChart") == true) {
				// backward compat on events since its caused problems
				var eventTypesToString:Map<Int, String> = [
					-1 => "HScript Call",
					0 => "Unknown",
					1 => "Camera Movement",
					2 => "BPM Change",
					3 => "Alt Animation Toggle",
				];

				if (data.events == null) data.events = [];
				for (event in cast(data.events, Array<Dynamic>)) {
					if (Reflect.hasField(event, "type")) {
						if(event.type != null)
							event.name = eventTypesToString[event.type];
						Reflect.deleteField(event, "type");
					}
				}

				// codename chart
				base = data;
			} else {
				// base game chart
				FNFLegacyParser.parse(data, base);
			}
			#end
		}

		if (base.meta == null)
			base.meta = loadChartMeta(songName, difficulty, base.fromMods);
		else {
			var loadedMeta = loadChartMeta(songName, difficulty, base.fromMods);
			for(field in Reflect.fields(base.meta)) {
				var f = Reflect.field(base.meta, field);
				if (f != null)
					Reflect.setField(loadedMeta, field, f);
			}
			base.meta = loadedMeta;
		}

		/**
		 * events.json LOADING
		 */
		#if REGION
		var extraEvents:Array<ChartEvent> = loadEventsJson(songName);
		if (extraEvents != null)
			base.events = base.events.concat(extraEvents);
		#end

		return base;
	}

	public static function addNoteType(chart:ChartData, noteTypeName:String):Int {
		switch(noteTypeName.trim()) {
			case "Default Note" | null | "":
				return 0;
			default:
				var index = chart.noteTypes.indexOf(noteTypeName);
				if (index > -1)
					return index+1;
				chart.noteTypes.push(noteTypeName);
				return chart.noteTypes.length;
		}
	}

	/**
	 * Saves the chart to the specific song folder path.
	 * @param songFolderPath Path to the song folder (ex: `mods/your mod/songs/song/`)
	 * @param chart Chart to save
	 * @param difficulty Name of the difficulty
	 * @param saveSettings
	 * @return Filtered chart used for saving.
	 */
	public static function save(songFolderPath:String, chart:ChartData, difficulty:String = "normal", ?saveSettings:ChartSaveSettings):ChartData {
		if (saveSettings == null) saveSettings = {};

		if (saveSettings.saveMetaInChart == null) saveSettings.saveMetaInChart = true;
		if (saveSettings.saveEventsInChart == null) saveSettings.saveEventsInChart = true;

		var filteredChart = filterChartForSaving(chart, saveSettings.saveMetaInChart, saveSettings.saveEventsInChart);
		var meta = filteredChart.meta;

		#if sys
		var saveFolder:String = saveSettings.folder == null ? "charts" : saveSettings.folder;

		if (!FileSystem.exists('${songFolderPath}/$saveFolder/'))
			FileSystem.createDirectory('${songFolderPath}/$saveFolder/');

		var chartPath = '${songFolderPath}/$saveFolder/${difficulty.trim()}.json';
		var metaPath = '${songFolderPath}/meta.json';

		CoolUtil.safeSaveFile(chartPath, Json.stringify(filteredChart, null, saveSettings.prettyPrint == true ? "\t" : null));

		// idk how null reacts to it so better be sure
		if (saveSettings.overrideExistingMeta == true || !FileSystem.exists(metaPath))
			CoolUtil.safeSaveFile(metaPath, Json.stringify(meta, null, saveSettings.prettyPrint == true ? "\t" : null));
		#end
		return filteredChart;
	}

	public static function filterChartForSaving(chart:ChartData, ?saveMetaInChart:Null<Bool>, ?saveEventsInChart:Null<Bool>):ChartData {
		var data = Reflect.copy(chart); // make a copy of the chart to leave the OG intact
		if (saveMetaInChart != true) {
			data.meta = null;
		} else {
			data.meta = Reflect.copy(chart.meta); // also make a copy of the metadata to leave the OG intact.
			if(data.meta != null && Reflect.hasField(data.meta, "parsedColor")) Reflect.deleteField(data.meta, "parsedColor");
		}

		data.events = saveEventsInChart != true ? null : Reflect.copy(chart.events);  // same here once again
		data.fromMods = null;

		var sortedData:Dynamic = {};
		for(f in Reflect.fields(data)) {
			var v = Reflect.field(data, f);
			if (v != null)
				Reflect.setField(sortedData, f, v);
		}
		return sortedData;
	}
}

typedef ChartSaveSettings = {
	var ?overrideExistingMeta:Bool;
	var ?saveMetaInChart:Bool;
	var ?saveEventsInChart:Bool;
	var ?prettyPrint:Bool;
	var ?folder:String;
}