import * as path from "path";
import * as escodegen from "escodegen";
import { BundleSource } from "../BundleSource";
import { File, ScriptTarget } from "./File";
import { Log } from "../Log";
import * as NativeEmitter from "events";
import { IPackageInformation, IPathInformation, AllowedExtenstions } from "./PathMaster";
import { ModuleCollection } from "./ModuleCollection";
import { ModuleCache } from "../ModuleCache";
import { EventEmitter } from "../EventEmitter";
import { utils } from "realm-utils";
import { ensureDir, removeFolder } from "../Utils";
import { SourceChangedEvent } from "../devServer/Server";
import { registerDefaultAutoImportModules, AutoImportedModule } from "./AutoImportedModule";
import { Defer } from "../Defer";
import { UserOutput } from "./UserOutput";
import { FuseBox } from "./FuseBox";
import { Bundle } from "./Bundle";
import { BundleProducer } from "./BundleProducer";
import { QuantumSplitConfig, QuantumSplitResolveConfiguration } from "../quantum/plugin/QuantumSplit";
import { isPolyfilledByFuseBox } from "./ServerPolyfillList";
import { CSSDependencyExtractor, ICSSDependencyExtractorOptions } from "../lib/CSSDependencyExtractor";
import { ExtensionOverrides } from "./ExtensionOverrides";
import { TypescriptConfig } from "./TypescriptConfig";
import { QuantumBit } from "../quantum/plugin/QuantumBit";

const appRoot = require("app-root-path");

/**
 * All the plugin method names
 */
export type PluginMethodName =
    "init"
    | "preBuild"
    | "preBundle"
    | "bundleStart"
    | "bundleEnd"
    | "postBundle"
    | "postBuild";

/**
 * Interface for a FuseBox plugin
 */
export interface Plugin {
    test?: RegExp;
    options?: any;
    init?(context: WorkFlowContext): any;
    transform?(file: File, ast?: any): any;
    transformGroup?(file: File): any;
    onTypescriptTransform?(file: File): any;
    bundleStart?(context: WorkFlowContext): any;
    bundleEnd?(context: WorkFlowContext): any;
    producerEnd?(producer: BundleProducer): any;
    onSparky?(): any;
    /**
     * If provided then the dependencies are loaded on the client
     *  before the plugin is invoked
     */
    dependencies?: string[];
}

/**
 * Gets passed to each plugin to track FuseBox configuration
 */
export class WorkFlowContext {
    /**
     * defaults to app-root-path, but can be set by user
     * @see FuseBox
     */
    public appRoot: any = appRoot.path;

    public dynamicImportsEnabled = true;

    public shim: any;

    public writeBundles = true;

    public fuse: FuseBox;

    public useTypescriptCompiler = false;

    public userWriteBundles = true;

    public showWarnings = true;

    public ensureTsConfig = true;

    public useJsNext: boolean | string[] = false;

    public showErrors = true;

    public showErrorsInBrowser = true;

    public sourceChangedEmitter = new EventEmitter<SourceChangedEvent>();

    public emitter = new NativeEmitter();

    public quantumBits = new Map<string, QuantumBit>();

    /**
     * The default package name or the package name configured in options
     */
    public defaultPackageName = "default";

    public transformTypescript?: (contents: string) => string;

    public ignoreGlobal: string[] = [];

    public pendingPromises: Promise<any>[] = [];

    public emitHMRDependencies = false;
    public languageLevel: ScriptTarget;
    public forcedLanguageLevel: ScriptTarget;


    public filterFile: { (file: File): boolean }

    public polyfillNonStandardDefaultUsage: boolean | string[] = false;

    public customAPIFile: string;

    public defaultEntryPoint: string;

    public output: UserOutput;

    public extensionOverrides?: ExtensionOverrides;

    public hash: string | Boolean;

    public target: string = "universal";
    /**
     * Explicitly target bundle to server
     */
    public serverBundle = false;

    public nodeModules: Map<string, ModuleCollection> = new Map();

    public libPaths: Map<string, IPackageInformation> = new Map();

    public homeDir: string;

    public printLogs = true;

    public runAllMatchedPlugins = false;

    public plugins: Plugin[];

    public fileGroups: Map<string, File>;

    public useCache = true;

    public doLog = true;

    public cache: ModuleCache;

    public tsConfig: TypescriptConfig;

    public customModulesFolder: string;

    public tsMode = false;

    public loadedTsConfig: string;

    public dependents = new Map<string, Set<string>>();

    public globals: { [packageName: string]: /** Variable name */ string };

    public standaloneBundle: boolean = true;

    public source: BundleSource;

    public sourceMapsProject: boolean = false;
    public sourceMapsVendor: boolean = false;
    public inlineSourceMaps: boolean = true;
    public sourceMapsRoot: string = "";
    public useSourceMaps: boolean;

    public initialLoad = true;

    public debugMode = false;

    public quantumSplitConfig: QuantumSplitConfig = new QuantumSplitConfig(this)

    public log: Log = new Log(this);

    public pluginTriggers: Map<string, Set<String>>;

    public natives = {
        process: true,
        stream: true,
        Buffer: true,
        http: true,
    }
    public autoImportConfig = {};

    public bundle: Bundle;

    public storage: Map<string, any>;

    public aliasCollection: any[];

    public experimentalAliasEnabled = false;

    public customCodeGenerator: any;

    public defer = new Defer;

    public cacheType = 'file';

    public initCache() {
        this.cache = new ModuleCache(this);
    }

    public resolve() {
        return Promise.all(this.pendingPromises).then(() => {
            this.pendingPromises = [];
        });
    }

    public queue(obj: any) {
        this.pendingPromises.push(obj);
    }


    public convertToFuseBoxPath(name: string) {
        let root = this.homeDir;
        name = name.replace(/\\/g, "/");
        root = root.replace(/\\/g, "/");
        name = name.replace(root, "").replace(/^\/|\\/, "");
        return name;
    }
    public isBrowserTarget() {
        return this.target === "browser";
    }

    public shouldPolyfillNonStandardDefault(file: File) {
        if (file.belongsToProject()) {
            return false;
        }
        let collectionName = file.collection && file.collection.name;
        if (collectionName === "fuse-heresy-default") {
            return false;
        }
        if (this.polyfillNonStandardDefaultUsage === true) {
            return true;
        }
        if (Array.isArray(this.polyfillNonStandardDefaultUsage)) {
            return this.polyfillNonStandardDefaultUsage.indexOf(collectionName) > -1
        }
    }

    public shouldUseJsNext(libName: string) {
        if (this.useJsNext === true) {
            return true;
        }
        if (Array.isArray(this.useJsNext)) {

            return this.useJsNext.indexOf(libName) > -1
        }
    }

    public nameSplit(name: string, filePath: string) {
        this.quantumSplitConfig.register(name, filePath);
    }

    public configureQuantumSplitResolving(opts: QuantumSplitResolveConfiguration) {
        this.quantumSplitConfig.resolveOptions = opts;
    }

    public setCodeGenerator(fn: any) {
        this.customCodeGenerator = fn;
    }

    public generateCode(ast: any, opts?: any) {
        if (this.customCodeGenerator) {
            try {
                return this.customCodeGenerator(ast);
            } catch (e) { }
        }
        return escodegen.generate(ast, opts);
    }

    public replaceAliases(requireStatement: string)
        : { requireStatement: string, replaced: boolean } {
        const aliasCollection = this.aliasCollection;
        let replaced = false;
        if (aliasCollection) {
            aliasCollection.forEach(props => {
                if (props.expr.test(requireStatement)) {
                    replaced = true;
                    requireStatement = requireStatement.replace(props.expr, `${props.replacement}$2`);
                }
            });
        }
        return { requireStatement, replaced };
    }

    public emitJavascriptHotReload(file: File) {
        if (file.ignoreCache) {
            return
        }

        let content = file.contents;
        if (file.context.emitHMRDependencies) {
            this.emitter.addListener("bundle-collected", () => {
                if (file.headerContent) {
                    content = file.headerContent.join("\n") + "\n" + content;
                }
                let dependants = {};
                this.dependents.forEach((set, key) => {
                    dependants[key] = [...set];
                });
                this.sourceChangedEmitter.emit({
                    type: "js",
                    content,
                    dependants: dependants,
                    path: file.info.fuseBoxPath,
                });
            });
        } else {
            if (file.headerContent) {
                content = file.headerContent.join("\n") + "\n" + content;
            }
            this.sourceChangedEmitter.emit({
                type: "js",
                content,
                path: file.info.fuseBoxPath,
            });
        }
    }

    public debug(group: string, text: string) {
        if (this.debugMode) {
            this.log.echo(`${group} : ${text}`);
        }
    }

    public nukeCache() {
        this.resetNodeModules();
        if (this.cache) {
            removeFolder(this.cache.cacheFolder);
            this.cache.initialize();
        }
    }

    public setSourceMapsProperty(params: any) {
        if (typeof params === "boolean") {
            this.sourceMapsProject = params;
        } else {
            if (utils.isPlainObject(params)) {
                this.sourceMapsProject = params.project !== undefined ? params.project : true;
                this.sourceMapsVendor = params.vendor === true;
                if (params.inline !== undefined) {
                    this.inlineSourceMaps = params.inline;
                }
                if (params.sourceRoot || params.sourceRoot === '') {
                    this.sourceMapsRoot = params.sourceRoot;
                }
            }
        }
        if (this.sourceMapsProject || this.sourceMapsVendor) {
            this.useSourceMaps = true;
        }
    }

    public warning(str: string) {
        return this.log.echoWarning(str);
    }

    public fatal(str: string) {
        throw new Error(str);
    }
    public debugPlugin(plugin: Plugin, text: string) {
        const name = plugin.constructor && plugin.constructor.name ? plugin.constructor.name : "Unknown";
        this.debug(name, text);
    }

    public isShimed(name: string): boolean {
        if (!this.shim) {
            return false;
        }
        return this.shim[name] !== undefined;
    }

    public isHashingRequired() {
        const hashOption = this.hash;
        let useHash = false;
        if (typeof hashOption === "string") {
            if (hashOption !== "md5") {
                throw new Error(`Uknown algorythm ${hashOption}`)
            }
            useHash = true;
        }
        if (hashOption === true) {
            useHash = true;
        }
        return useHash;
    }

    /**
     * Resets significant class members
     */
    public reset() {
        this.log.reset();
        this.dependents = new Map<string, Set<string>>();
        this.emitter = new NativeEmitter();
        this.storage = new Map();
        this.source = new BundleSource(this);
        this.nodeModules = new Map();
        this.pluginTriggers = new Map();
        this.fileGroups = new Map();
        this.libPaths = new Map();
    }

    public registerDependant(target: File, dependant: File) {

        let fileSet: Set<string>;
        if (!this.dependents.has(target.info.fuseBoxPath)) {
            fileSet = new Set<string>();
            this.dependents.set(target.info.fuseBoxPath, fileSet);
        } else {
            fileSet = this.dependents.get(target.info.fuseBoxPath);
        }
        if (!fileSet.has(dependant.info.fuseBoxPath)) {
            fileSet.add(dependant.info.fuseBoxPath);
        }
    }

    public initAutoImportConfig(userNatives, userImports) {
        if (this.target !== "server") {
            this.autoImportConfig = registerDefaultAutoImportModules(userNatives);
            if (utils.isPlainObject(userImports)) {
                for (let varName in userImports) {
                    this.autoImportConfig[varName] = new AutoImportedModule(varName, userImports[varName]);
                }
            }
        }
    }

    public setItem(key: string, obj: any) {
        this.storage.set(key, obj);
    }

    public getItem(key: string, defaultValue?: any): any {
        return this.storage.get(key) !== undefined ? this.storage.get(key) : defaultValue;
    }

    public setCSSDependencies(file: File, userDeps: string[]) {
        let collection = this.getItem("cssDependencies") || {};
        collection[file.info.absPath] = userDeps;
        this.setItem("cssDependencies", collection);
    }

    public extractCSSDependencies(file: File, opts: ICSSDependencyExtractorOptions): string[] {
        const extractor = CSSDependencyExtractor.init(opts);
        this.setCSSDependencies(file, extractor.getDependencies())
        return extractor.getDependencies();
    }

    public getCSSDependencies(file: File): string[] {
        let collection = this.getItem("cssDependencies") || {};
        return collection[file.info.absPath];
    }
    /**
     * Create a new file group
     * Mocks up file
     */
    public createFileGroup(name: string, collection: ModuleCollection, handler: Plugin): File {
        let info = <IPathInformation>{
            fuseBoxPath: name,
            absPath: name,
        };
        let file = new File(this, info);
        file.collection = collection;
        file.contents = "";
        file.groupMode = true;
        // Pass it along
        // Transformation might happen in a different plugin
        file.groupHandler = handler;

        this.fileGroups.set(name, file);
        return file;
    }

    public getFileGroup(name: string): File {
        return this.fileGroups.get(name);
    }

    public allowExtension(ext: string) {
        if (!AllowedExtenstions.has(ext)) {
            AllowedExtenstions.add(ext);
        }
    }

    public addAlias(obj: any, value?: any) {
        const aliases = [];
        if (!value) {
            for (const key in obj) {
                if (obj.hasOwnProperty(key)) {
                    if (path.isAbsolute(key)) {
                        // dying in agony
                        this.fatal(`Can't use absolute paths with alias "${key}"`);
                    }

                    aliases.push({ expr: new RegExp(`^(${key})(/|$)`), replacement: obj[key] });
                }
            }
        } else {
            aliases.push({ expr: new RegExp(`^(${obj})(/|$)`), replacement: value });
        }

        this.aliasCollection = this.aliasCollection || [];
        this.aliasCollection = this.aliasCollection.concat(aliases)
        this.experimentalAliasEnabled = true;
    }
    public setHomeDir(dir: string) {
        this.homeDir = ensureDir(dir);
    }

    public setLibInfo(name: string, version: string, info: IPackageInformation) {
        let key = `${name}@${version}`;
        if (!this.libPaths.has(key)) {
            return this.libPaths.set(key, info);
        }
    }

    /** Converts the file extension from `.ts` to `.js` */
    public convert2typescript(name: string) {
        return name.replace(/\.ts$/, ".js");
    }

    public getLibInfo(name: string, version: string): IPackageInformation {
        let key = `${name}@${version}`;
        if (this.libPaths.has(key)) {
            return this.libPaths.get(key);
        }
    }

    public setPrintLogs(printLogs: boolean) {
        this.printLogs = printLogs;
    }

    public setUseCache(useCache: boolean) {
        this.useCache = useCache;
    }

    public hasNodeModule(name: string): boolean {
        return this.nodeModules.has(name);
    }

    public isGlobalyIgnored(name: string): boolean {
        if (this.ignoreGlobal.indexOf(name) > -1) {
            return true;
        }
        if (this.target === "server") {
            return isPolyfilledByFuseBox(name)
        }

    }

    public resetNodeModules() {
        this.nodeModules = new Map<string, ModuleCollection>();
    }

    public addNodeModule(name: string, collection: ModuleCollection) {
        this.nodeModules.set(name, collection);
    }

    public isFirstTime() {
        return this.initialLoad === true;
    }

    public writeOutput(outFileWritten?: () => any) {
        this.initialLoad = false;

        const res = this.source.getResult();
        if (this.bundle) {

            this.bundle.generatedCode = res.content;
        }

        if (this.output && (!this.bundle || this.bundle && this.bundle.producer.writeBundles)) {
            this.output.writeCurrent(res.content).then(() => {

                if (this.source.includeSourceMaps) {
                    this.writeSourceMaps(res);
                }

                this.defer.unlock();
                if (utils.isFunction(outFileWritten)) {
                    outFileWritten();
                }
            });
        } else {

            this.defer.unlock();
            outFileWritten();
        }
    }

    protected writeSourceMaps(result: any) {
        // Writing sourcemaps
        if ((this.sourceMapsProject || this.sourceMapsVendor)) {
            this.output.writeToOutputFolder(`${this.output.filename}.js.map`, result.sourceMap);
        }
    }

    public getNodeModule(name: string): ModuleCollection {
        return this.nodeModules.get(name);
    }

    /**
     * @param fn if provided, its called once the plugin method has been triggered
     */
    public triggerPluginsMethodOnce(name: PluginMethodName, args: any, fn?: { (plugin: Plugin): void }) {
        this.plugins.forEach(plugin => {
            if (Array.isArray(plugin)) {
                plugin.forEach(p => {
                    if (utils.isFunction(p[name])) {
                        if (this.pluginRequiresTriggering(p, name)) {
                            p[name].apply(p, args);
                            if (fn) {
                                fn(p);
                            }
                        }
                    }
                });
            }
            if (plugin && utils.isFunction(plugin[name])) {
                if (this.pluginRequiresTriggering(plugin, name)) {
                    plugin[name].apply(plugin, args);
                    if (fn) {
                        fn(plugin);
                    }
                }
            }
        });
    }

    /**
     * Makes sure plugin method is triggered only once
     * @returns true if the plugin needs triggering
     */
    private pluginRequiresTriggering(cls: any, method: PluginMethodName) {
        if (!cls.constructor) {
            return true;
        }
        let name = cls.constructor.name;
        if (!this.pluginTriggers.has(name)) {
            this.pluginTriggers.set(name, new Set());
        }
        let items = this.pluginTriggers.get(name);
        if (!items.has(method)) {
            items.add(method);
            return true;
        }
        return false;
    }
}