import {getClient} from "../utils/database.js";
import {query} from "express-validator";


export async function create(req, res) {
    const channel = {
        name: req.body.name,
        description: req.body.description,
        owner: req.body.owner,
    }

    const client = await getClient();

    const query = `INSERT INTO channels (name, description, owner) VALUES ('${channel.name}', '${channel.description}', ${channel.owner})`;

    await client.query(query);

    const logger = req.body.logger;
    logger.action("try to create new channel with owner " + channel.owner + " and name " + channel.name);

    logger.write("Successfully created new channel with name " + channel.name, 200);
    res.status(200).json(channel);
}

export async function getById(req, res) {
    const id = req.params.id;

    const logger = req.body.logger;
    logger.action("try to get channel with id " + id);
    const client = await getClient();
    const query = `SELECT * FROM channels WHERE id = ${id}`;
    const result = await client.query(query);
    logger.write("Successfully get channel with id " + id, 200);
    res.status(200).json(result);

}

export async function getAll(req, res) {
    const logger = req.body.logger;
    logger.action("try to get all channels");
    const client = await getClient();

    const query = `SELECT * FROM channels`;
    const channels = await client.query(query);

    let result = []

    for (const channelNbr in channels.rows) {
        const channel = channels.rows[channelNbr];
        const subQuery = `SELECT * FROM subscriptions WHERE channel = ${channel.id}`;
        const subResult = await client.query(subQuery);
        if (subResult.rows.length > 0) {
            channel.subscriptions = subResult.rows.length;
            result.push(channel);
        } else {
            channel.subscriptions = 0;
            result.push(channel);
        }
    }

    result.sort((a, b) => {
        var keyA = a.subscriptions;
        var keyB = b.subscriptions;
        if (keyA > keyB) return 1;
        if (keyA < keyB) return -1;
    })

    logger.write("Successfully get all channels", 200);
    res.status(200).json(result);
}

export async function update(req, res) {
    const id = req.params.id;
    const channel = {
        name: req.body.name,
        description: req.body.description,
    }

    const client = await getClient();
    const logger = req.body.logger;
    logger.action("try to update channel with id " + req.params.id);

    const channelQuery = `SELECT * FROM channels WHERE id = ${req.params.id}`;
    const channelResult = await client.query(channelQuery);
    const channelInBase = channelResult.rows[0];

    if (channelInBase.name !== channel.name) {
        const nameQuery = `SELECT name FROM channels WHERE name = '${channel.name}'`;
        const nameResult = await client.query(nameQuery);
        if (nameResult.rows.length > 0) {
            logger.write("failed to update channel because name already taken", 400);
            res.status(400).json({error: 'Name already used'});
            return
        }
    }

    const updateQuery = `UPDATE channels SET name = '${channel.name}', description = '${channel.description}' WHERE id = ${id}`;
    await client.query(updateQuery);
    logger.write("Successfully updated channel", 200);
    res.status(200).json(channel);

}

export async function del(req, res) {
    const id = req.params.id;
    const logger = req.body.logger;
    logger.action("try to delete channel with id " + id);
    const client = await getClient();
    const query = `DELETE FROM channels WHERE id = ${id}`;
    await client.query(query);
    logger.write("Successfully deleted channel", 200);
    res.status(200).json({message: 'Successfully deleted'});
}

export async function toggleSubscription(req, res) {
    const id = req.params.id;
    const userId = req.body.userId;
    const logger = req.body.logger;
    logger.action("try to toggle subscription for channel with id " + id);

    const client = await getClient();
    const query = `SELECT * FROM subscriptions WHERE channel = ${id} AND owner = ${userId}`;
    const result = await client.query(query);

    if (result.rows.length > 0) {
        // Unsubscribe
        const deleteQuery = `DELETE FROM subscriptions WHERE channel = ${id} AND owner = ${userId}`;
        await client.query(deleteQuery);
        logger.write("Successfully unsubscribed from channel", 200);
        res.status(200).json({message: 'Unsubscribed successfully'});
    } else {
        // Subscribe
        const insertQuery = `INSERT INTO subscriptions (channel, owner) VALUES (${id}, ${userId})`;
        await client.query(insertQuery);
        logger.write("Successfully subscribed to channel", 200);
        res.status(200).json({message: 'Subscribed successfully'});
    }
}