const { EventEmitter } = require("events");

class WatchedGuild extends EventEmitter {
    constructor() {
        super();

        this.knownWebhooks = new Map();
        this.eventStack = [];
        this.upstreamGuildId = null;
    }

    pushEvent(e) {
        this.eventStack.push(e);
        this.emit("pushed", e);
    }

    consumeEvent() {
        return this.eventStack.pop();
    }

    consumeAll() {
        const events = [...this.eventStack];
        this.eventStack = [];
        return events;
    }

    hasEvents() {
        return this.eventStack.length > 0;
    }

    _pushMessageEvent(message) {
        this.pushEvent({
            eventType: "messageCreate",
            message: message.toJSON()
        });
    }

    discordConnect(bot) {
        this.bot = bot;
        this.bot.on("messageCreate", (message) => {
            if (message.guildId !== this.upstreamGuildId)
                return;

            this._pushMessageEvent(message);
        });
    }

    async discordSendMessage(messageContent, channelId, username, avatarURL=undefined) {
        if (!this.bot)
            throw new Error("Bot not connected");

        let webhook = this.knownWebhooks.get(channelId);
        if (!webhook) {
            webhook = (await this.bot.getChannelWebhooks(channelId))
                .filter(w => w.name == "well_known__bridge")[0];

            if (!webhook)
                webhook = await this.bot.createChannelWebhook(channelId, {
                    name: "well_known__bridge"
                }, "This webhook was created by the bridge API bot.");

            this.knownWebhooks.set(channelId, webhook);
        }

        await this.bot.executeWebhook(webhook.id, webhook.token, {
            allowedMentions: {
                everyone: false,
                roles: false,
                users: true
            },
            content: messageContent,
            tts: false,
            wait: true,
            avatarURL,
            username
        });
    }
}

module.exports = WatchedGuild;