import {MusicClientEntry, SongInfo} from "tc-shared/ui/client";
import {PlaylistSong} from "tc-shared/connection/ServerConnectionDeclaration";
import {guid} from "tc-shared/crypto/uid";
import * as React from "react";

export interface Event<Events, T = keyof Events> {
    readonly type: T;
    as<T extends keyof Events>() : Events[T];
}

interface SingletonEvents {
    "singletone-instance": never;
}

export class SingletonEvent implements Event<SingletonEvents, "singletone-instance"> {
    static readonly instance = new SingletonEvent();

    readonly type = "singletone-instance";
    private constructor() { }
    as<T extends keyof SingletonEvents>() : SingletonEvents[T] { return; }
}

const event_annotation_key = guid();
export class Registry<Events> {
    private readonly registry_uuid;

    private handler: {[key: string]: ((event) => void)[]} = {};
    private connections: {[key: string]:Registry<string>[]} = {};
    private event_handler_objects: {
        object: any,
        handlers: {[key: string]: ((event) => void)[]}
    }[] = [];
    private debug_prefix = undefined;
    private warn_unhandled_events = true;

    constructor() {
        this.registry_uuid = "evreg_data_" + guid();
    }


    enable_debug(prefix: string) { this.debug_prefix = prefix || "---"; }
    disable_debug() { this.debug_prefix = undefined; }

    enable_warn_unhandled_events() { this.warn_unhandled_events = true; }
    disable_warn_unhandled_events() { this.warn_unhandled_events = false; }

    on<T extends keyof Events>(event: T, handler: (event?: Events[T] & Event<Events, T>) => void);
    on(events: (keyof Events)[], handler: (event?: Event<Events, keyof Events>) => void);
    on(events, handler) {
        if(!Array.isArray(events))
            events = [events];

        handler[this.registry_uuid] = {
            singleshot: false
        };
        for(const event of events) {
            const handlers = this.handler[event] || (this.handler[event] = []);
            handlers.push(handler);
        }
    }

    /* one */
    one<T extends keyof Events>(event: T, handler: (event?: Events[T] & Event<Events, T>) => void);
    one(events: (keyof Events)[], handler: (event?: Event<Events, keyof Events>) => void);
    one(events, handler) {
        if(!Array.isArray(events))
            events = [events];

        for(const event of events) {
            const handlers = this.handler[event] || (this.handler[event] = []);

            handler[this.registry_uuid] = { singleshot: true };
            handlers.push(handler);
        }
    }

    off<T extends keyof Events>(handler: (event?: Event<Events, T>) => void);
    off<T extends keyof Events>(event: T, handler: (event?: Event<Events, T>) => void);
    off(event: (keyof Events)[], handler: (event?: Event<Events, keyof Events>) => void);
    off(handler_or_events, handler?) {
        if(typeof handler_or_events === "function") {
            for(const key of Object.keys(this.handler))
                this.handler[key].remove(handler_or_events);
        } else {
            if(!Array.isArray(handler_or_events))
                handler_or_events = [handler_or_events];

            for(const event of handler_or_events) {
                const handlers = this.handler[event];
                if(handlers) handlers.remove(handler);
            }
        }
    }

    connect<EOther, T extends keyof Events & keyof EOther>(events: T | T[], target: Registry<EOther>) {
        for(const event of Array.isArray(events) ? events : [events])
            (this.connections[event as string] || (this.connections[event as string] = [])).push(target as any);
    }

    disconnect<EOther, T extends keyof Events & keyof EOther>(events: T | T[], target: Registry<EOther>) {
        for(const event of Array.isArray(events) ? events : [events])
            (this.connections[event as string] || []).remove(target as any);
    }

    disconnect_all<EOther>(target: Registry<EOther>) {
        for(const event of Object.keys(this.connections))
            this.connections[event].remove(target as any);
    }

    fire<T extends keyof Events>(event_type: T, data?: Events[T]) {
        if(this.debug_prefix) console.log("[%s] Trigger event: %s", this.debug_prefix, event_type);

        const event = Object.assign(typeof data === "undefined" ? SingletonEvent.instance : data, {
            type: event_type,
            as: function () { return this; }
        });

        let invoke_count = 0;
        for(const handler of (this.handler[event_type as string] || [])) {
            handler(event);
            invoke_count++;

            const reg_data = handler[this.registry_uuid];
            if(typeof reg_data === "object" && reg_data.singleshot)
                this.handler[event_type as string].remove(handler);
        }

        for(const evhandler of (this.connections[event_type as string] || [])) {
            evhandler.fire(event_type as any, event as any);
            invoke_count++;
        }
        if(invoke_count === 0) {
            console.warn("Event handler (%s) triggered event %s which has no consumers.", this.debug_prefix, event_type);
        }
    }

    fire_async<T extends keyof Events>(event_type: T, data?: Events[T]) {
        setTimeout(() => this.fire(event_type, data));
    }

    destroy() {
        this.handler = {};
        this.connections = {};
        this.event_handler_objects = [];
    }

    register_handler(handler: any) {
        if(typeof handler !== "object")
            throw "event handler must be an object";
        const proto = Object.getPrototypeOf(handler);
        if(typeof proto !== "object")
            throw "event handler must have a prototype";

        let registered_events = {};
        for(const function_name of Object.getOwnPropertyNames(proto)) {
            if(function_name === "constructor") continue;
            if(typeof proto[function_name][event_annotation_key] !== "object") continue;

            const event_data = proto[function_name][event_annotation_key];
            const ev_handler = event => proto[function_name].call(handler, event);
            for(const event of event_data.events) {
                registered_events[event] = registered_events[event] || [];
                registered_events[event].push(ev_handler);
                this.on(event, ev_handler);
            }
        }
        if(Object.keys(registered_events).length === 0)
            throw "no events found in event handler";

        this.event_handler_objects.push({
            handlers: registered_events,
            object: handler
        });
    }

    unregister_handler(handler: any) {
        const data = this.event_handler_objects.find(e => e.object === handler);
        if(!data) throw "unknown event handler";
        this.event_handler_objects.remove(data);

        for(const key of Object.keys(data.handlers)) {
            for(const evhandler of data.handlers[key])
                this.off(evhandler);
        }
    }
}

export function EventHandler<EventTypes>(events: (keyof EventTypes) | (keyof EventTypes)[]) {
    return function (target: any,
                     propertyKey: string,
                     descriptor: PropertyDescriptor) {
        if(typeof target[propertyKey] !== "function")
            throw "Invalid event handler annotation. Expected to be on a function type.";

        target[propertyKey][event_annotation_key] = {
            events: Array.isArray(events) ? events : [events]
        };
    }
}

export function ReactEventHandler<ObjectClass = React.Component<any, any>, EventTypes = any>(registry_callback: (object: ObjectClass) => Registry<EventTypes>) {
    return function (constructor: Function) {
        if(!React.Component.prototype.isPrototypeOf(constructor.prototype))
            throw "Class/object isn't an instance of React.Component";

        const didMount = constructor.prototype.componentDidMount;
        constructor.prototype.componentDidMount = function() {
            const registry = registry_callback(this);
            if(!registry) throw "Event registry returned for an event object is invalid";
            registry.register_handler(this);

            if(typeof didMount === "function")
                didMount.call(this, arguments);
        };

        const willUnmount = constructor.prototype.componentWillUnmount;
        constructor.prototype.componentWillUnmount = function () {
            const registry = registry_callback(this);
            if(!registry) throw "Event registry returned for an event object is invalid";
            registry.unregister_handler(this);

            if(typeof willUnmount === "function")
                willUnmount.call(this, arguments);
        };
    }
}

export namespace channel_tree {
    export interface client {
        "enter_view": {},
        "left_view": {},

        "property_update": {
            properties: string[]
        },

        "music_status_update": {
            player_buffered_index: number,
            player_replay_index: number
        },
        "music_song_change": {
            "song": SongInfo
        },

        /* TODO: Move this out of the music bots interface? */
        "playlist_song_add": { song: PlaylistSong },
        "playlist_song_remove": { song_id: number },
        "playlist_song_reorder": { song_id: number, previous_song_id: number },
        "playlist_song_loaded": { song_id: number, success: boolean, error_msg?: string, metadata?: string },
    }
}

export namespace sidebar {
    export interface music {
        "open": {}, /* triggers when frame should be shown */
        "close": {}, /* triggers when frame will be closed */

        "bot_change": {
            old: MusicClientEntry | undefined,
            new: MusicClientEntry | undefined
        },
        "bot_property_update": {
            properties: string[]
        },

        "action_play": {},
        "action_pause": {},
        "action_song_set": { song_id: number },
        "action_forward": {},
        "action_rewind": {},
        "action_forward_ms": {
            units: number;
        },
        "action_rewind_ms": {
            units: number;
        },
        "action_song_add": {},
        "action_song_delete": { song_id: number },
        "action_playlist_reload": {},

        "playtime_move_begin": {},
        "playtime_move_end": {
            canceled: boolean,
            target_time?: number
        },

        "reorder_begin": { song_id: number; entry: JQuery },
        "reorder_end": { song_id: number; canceled: boolean; entry: JQuery; previous_entry?: number },

        "player_time_update": channel_tree.client["music_status_update"],
        "player_song_change": channel_tree.client["music_song_change"],

        "playlist_song_add": channel_tree.client["playlist_song_add"] & { insert_effect?: boolean },
        "playlist_song_remove": channel_tree.client["playlist_song_remove"],
        "playlist_song_reorder": channel_tree.client["playlist_song_reorder"],
        "playlist_song_loaded": channel_tree.client["playlist_song_loaded"] & { html_entry?: JQuery },
    }
}

export namespace modal {
    export type BotStatusType = "name" | "description" | "volume" | "country_code" | "channel_commander" | "priority_speaker";
    export type PlaylistStatusType = "replay_mode" | "finished" | "delete_played" | "max_size" | "notify_song_change";
    export interface music_manage {
        show_container: { container: "settings" | "permissions"; };

        /* setting relevant */
        query_bot_status: {},
        bot_status: {
            status: "success" | "error";
            error_msg?: string;
            data?: {
                name: string,
                description: string,
                volume: number,

                country_code: string,
                default_country_code: string,

                channel_commander: boolean,
                priority_speaker: boolean,

                client_version: string,
                client_platform: string,

                uptime_mode: number,
                bot_type: number
            }
        },
        set_bot_status: {
            key: BotStatusType,
            value: any
        },
        set_bot_status_result: {
            key: BotStatusType,
            status: "success" | "error" | "timeout",
            error_msg?: string,
            value?: any
        }

        query_playlist_status: {},
        playlist_status: {
            status: "success" | "error",
            error_msg?: string,
            data?: {
                replay_mode: number,
                finished: boolean,
                delete_played: boolean,
                max_size: number,
                notify_song_change: boolean
            }
        },
        set_playlist_status: {
            key: PlaylistStatusType,
            value: any
        },
        set_playlist_status_result: {
            key: PlaylistStatusType,
            status: "success" | "error" | "timeout",
            error_msg?: string,
            value?: any
        }

        /* permission relevant */
        show_client_list: {},
        hide_client_list: {},

        filter_client_list: { filter: string | undefined },

        "refresh_permissions": {},

        query_special_clients: {},
        special_client_list: {
            status: "success" | "error" | "error-permission",
            error_msg?: string,
            clients?: {
                name: string,
                unique_id: string,
                database_id: number
            }[]
        },

        search_client: { text: string },
        search_client_result: {
            status: "error" | "timeout" | "empty" | "success",
            error_msg?: string,
            client?: {
                name: string,
                unique_id: string,
                database_id: number
            }
        },

        /* sets a client to set the permission for */
        special_client_set: {
            client?: {
                name: string,
                unique_id: string,
                database_id: number
            }
        },

        "query_general_permissions": {},
        "general_permissions": {
            status: "error" | "timeout" | "success",
            error_msg?: string,
            permissions?: {[key: string]:number}
        },
        "set_general_permission_result": {
            status: "error" | "success",
            key: string,
            value?: number,
            error_msg?: string
        },
        "set_general_permission": { /* try to change a permission for the server */
            key: string,
            value: number
        },


        "query_client_permissions": { client_database_id: number },
        "client_permissions": {
            status: "error" | "timeout" | "success",
            client_database_id: number,
            error_msg?: string,
            permissions?: {[key: string]:number}
        },
        "set_client_permission_result": {
            status: "error" | "success",
            client_database_id: number,
            key: string,
            value?: number,
            error_msg?: string
        },
        "set_client_permission": { /* try to change a permission for the server */
            client_database_id: number,
            key: string,
            value: number
        },

        "query_group_permissions": { permission_name: string },
        "group_permissions": {
            permission_name: string;
            status: "error" | "timeout" | "success"
            groups?: {
                name: string,
                value: number,
                id: number
            }[],
            error_msg?: string
        }
    }

    export interface newcomer {
        "show_step": {
            "step": "welcome" | "microphone" | "identity" | "finish"
        },
        "exit_guide": {
            ask_yesno: boolean
        },

        "modal-shown": {},


        "step-status": {
            next_button: boolean,
            previous_button: boolean
        }
    }

    export namespace settings {
        export type ProfileInfo = {
            id: string,
            name: string,
            nickname: string,
            identity_type: "teaforo" | "teamspeak" | "nickname",

            identity_forum?: {
                valid: boolean,
                fallback_name: string
            },
            identity_nickname?: {
                name: string,
                fallback_name: string
            },
            identity_teamspeak?: {
                unique_id: string,
                fallback_name: string
            }
        }

        export interface profiles {
            "reload-profile": { profile_id?: string },
            "select-profile": { profile_id: string },

            "query-profile-list": { },
            "query-profile-list-result": {
                status: "error" | "success" | "timeout",

                error?: string;
                profiles?: ProfileInfo[]
            }

            "query-profile": { profile_id: string },
            "query-profile-result": {
                status: "error" | "success" | "timeout",
                profile_id: string,

                error?: string;
                info?: ProfileInfo
            },

            "select-identity-type": {
                profile_id: string,
                identity_type: "teamspeak" | "teaforo" | "nickname" | "unset"
            },

            "query-profile-validity": { profile_id: string },
            "query-profile-validity-result": {
                profile_id: string,
                status: "error" | "success" | "timeout",

                error?: string,
                valid?: boolean
            }

            "create-profile": { name: string },
            "create-profile-result": {
                status: "error" | "success" | "timeout",
                name: string;

                profile_id?: string;
                error?: string;
            },

            "delete-profile": { profile_id: string },
            "delete-profile-result": {
                status: "error" | "success" | "timeout",
                profile_id: string,
                error?: string
            }

            "set-default-profile": { profile_id: string },
            "set-default-profile-result": {
                status: "error" | "success" | "timeout",

                /* the profile which now has the id "default" */
                old_profile_id: string,

                /* the "default" profile which now has a new id */
                new_profile_id?: string

                error?: string;
            }

            /* profile name events */
            "set-profile-name": {
                profile_id: string,
                name: string
            },
            "set-profile-name-result": {
                status: "error" | "success" | "timeout",
                profile_id: string,
                name?: string
            },

            /* profile nickname events */
            "set-default-name": {
                profile_id: string,
                name: string | null
            },
            "set-default-name-result": {
                status: "error" | "success" | "timeout",
                profile_id: string,
                name?: string | null
            },

            "query-identity-teamspeak": { profile_id: string },
            "query-identity-teamspeak-result": {
                status: "error" | "success" | "timeout",
                profile_id: string,

                error?: string,
                level?: number
            }

            "set-identity-name-name": { profile_id: string, name: string },
            "set-identity-name-name-result": {
                status: "error" | "success" | "timeout",
                profile_id: string,

                error?: string,
                name?: string
            },

            "generate-identity-teamspeak": { profile_id: string },
            "generate-identity-teamspeak-result": {
                profile_id: string,
                status: "error" | "success" | "timeout",

                error?: string,

                level?: number
                unique_id?: string
            },

            "improve-identity-teamspeak-level": { profile_id: string },
            "improve-identity-teamspeak-level-update": {
                profile_id: string,
                new_level: number
            },

            "import-identity-teamspeak": { profile_id: string },
            "import-identity-teamspeak-result": {
                profile_id: string,

                level?: number
                unique_id?: string
            }

            "export-identity-teamspeak": {
                profile_id: string,
                filename: string
            },


            "setup-forum-connection": {}
        }

        export type MicrophoneSettings = "volume" | "vad-type" | "ppt-key" | "ppt-release-delay" | "ppt-release-delay-active" | "threshold-threshold";
        export interface microphone {
            "query-devices": { refresh_list: boolean },
            "query-device-result": {
                status: "success" | "error" | "timeout",

                error?: string,
                devices?: {
                    id: string,
                    name: string,
                    driver: string
                }[]
                active_device?: string;
            },

            "query-settings": {},
            "query-settings-result": {
                status: "success" | "error" | "timeout",

                error?: string,
                info?: {
                    volume: number,
                    vad_type: string,

                    vad_ppt: {
                        key: any, /* ppt.KeyDescriptor */
                        release_delay: number,
                        release_delay_active: boolean
                    },
                    vad_threshold: {
                        threshold: number
                    }
                }
            },

            "set-device": { device_id: string },
            "set-device-result": {
                device_id: string,
                status: "success" | "error" | "timeout",

                error?: string
            },

            "set-setting": {
                setting: MicrophoneSettings;
                value: any;
            },
            "set-setting-result": {
                setting: MicrophoneSettings,
                status: "success" | "error" | "timeout",

                error?: string,
                value?: any
            },

            "update-device-level": {
                devices: {
                    device_id: string,
                    status: "success" | "error",

                    level?: number,
                    error?: string
                }[]
            },

            "audio-initialized": {},
            "deinitialize": {}
        }
    }
}

//Some test code
const eclient = new Registry<channel_tree.client>();
const emusic = new Registry<sidebar.music>();

eclient.on("property_update", event => { event.as<"playlist_song_loaded">(); });
eclient.connect("playlist_song_loaded", emusic);
eclient.connect("playlist_song_loaded", emusic);