import { parseYaml } from "../util";
import { Command, ICommandData, Plugin } from "src/model/plugin";
import { tryDo } from "@shared/common/async_utils";
import * as t from "io-ts";
import { logger } from "src/logging";
import { getRepository } from "typeorm";
import { GiveRoleMessage } from "@shared/db/entity/GiveRoleMessage";
import { Message, MessageReaction, ReactionCollector, ReactionEmoji, TextChannel, User } from "discord.js";
import { client } from "src/client";

const ReactRoleMessageParams = t.type({
    message: t.string,
    roleId: t.string
});

const REACT_EMOTE = "⭐";
const MSG_COLOR = 9830318;

@Plugin
export class GiveRoleForReact {
    @Command({
        type: "mention",
        pattern: "add role message",
        documentation: {
            description: "Add role giver message",
            example: "add role message { message: \"This is a role!\", roleId: \"0237894783782\" }"
        },
        allowDM: false,
        auth: true
    })
    async makeRoleMessage({ message, contents }: ICommandData): Promise<void> {
        const textContent = (contents as string).substring("add role message".length).trim();
        
        tryDo(message.delete());

        const opts = parseYaml(ReactRoleMessageParams, textContent);
        if (!opts.ok) {
            await this.sendDM(message.author, `Sorry, I don't understand the command! Got the following errors: ${opts.errors.join("\n")}`);
            return;
        }

        const params = opts.result;

        if (!message.guild?.roles.cache.has(params.roleId)) {
            await this.sendDM(message.author, "Sorry, the role ID is not a valid role on the server!");
            return;
        }

        const msgSendResult = await tryDo(message.channel.send({
            embed: {
                title: `React with ${REACT_EMOTE} to gain role`,
                description: params.message,
                color: MSG_COLOR
            }
        }));

        if (!msgSendResult.ok) {
            logger.error(`GiveRoleForReact: failed to create message because ${msgSendResult.error}`);
            return;
        }

        const msg = msgSendResult.result;
        await msg.react(REACT_EMOTE);
        const roleGiveMessageRepo = getRepository(GiveRoleMessage);

        if (!msg.guild) {
            logger.error("GiveRoleForReact: tried to set up role react for DMs (this should never happen!)");
            return;
        }
        
        await roleGiveMessageRepo.save({
            messageId: msg.id,
            guildId: msg.guild.id,
            channelId: msg.channel.id,
            roleToGive: params.roleId
        });

        this.initReactCollector(msg, params.roleId);
    }

    private initReactCollector(msg: Message, role: string) {
        const check = (reaction: MessageReaction) => {
            return reaction.emoji.name == REACT_EMOTE;
        };
        const collector = new ReactionCollector(msg, check, {
            dispose: true
        });

        const guild = msg.guild;
        if (!guild) {
            throw new Error("Tried to initialize role collector for non-guild channel.");
        }

        collector.on("collect", async (_, user) => {
            if (user.bot) {
                return;
            }
            const gu = guild.member(user);
            if (!gu) {
                return;
            }
            const result = await tryDo(gu.roles.add(role));
            if (!result.ok) {
                logger.error("GiveRoleForReact: Can't add role %s to user %s: %s", role, gu.id, result.error);
            }
        });

        collector.on("remove", async (_, user) => {
            if (user.bot) {
                return;
            }
            const gu = guild.member(user);
            if (!gu) {
                return;
            }
            const result = await tryDo(gu.roles.remove(role));
            if (!result.ok) {
                logger.error("GiveRoleForReact: Can't remove role %s to user %s: %s", role, gu.id, result.error);
            }
        });
    }

    private async sendDM(usr: User, messageText: string) {
        const dmResult = await tryDo(usr.createDM());
        if (dmResult.ok) {
            tryDo(dmResult.result.send(messageText));
        }
    }

    async start(): Promise<void> {
        logger.info("Initializing role give messages");
        const roleGiveMessageRepo = getRepository(GiveRoleMessage);

        const reactMessages = await roleGiveMessageRepo.find();

        const staleEntities = [];
        for (const reactMessage of reactMessages) {
            const guildResult = await tryDo(client.bot.guilds.fetch(reactMessage.guildId));
            if (!guildResult.ok) {
                staleEntities.push(reactMessage);
                continue;
            }

            const guild = guildResult.result;
            const channel = guild.channels.resolve(reactMessage.channelId);
            if (!channel || !(channel instanceof TextChannel)) {
                staleEntities.push(reactMessage);
                continue;
            }

            const msgResult = await tryDo(channel.messages.fetch(reactMessage.messageId));
            if (!msgResult.ok) {
                staleEntities.push(reactMessage);
                continue;
            }
            
            this.initReactCollector(msgResult.result, reactMessage.roleToGive);
        }

        await roleGiveMessageRepo.remove(staleEntities);
    }
}