const { ActionRowBuilder, ButtonBuilder, ButtonStyle } = require('discord.js');
const { Octokit } = require('@octokit/rest');
const { createEmbed } = require('../utils/embeds');
const { Colors } = require('../config');

/**
 * Scans a channel for old drop embeds with broken GitHub Link buttons
 * and replaces them with new interactive download buttons (dl_<assetId>).
 *
 * Usage: fix downloads <channel_id>
 */
module.exports = {
    async execute(client, message, args) {
        const channelId = args[0]?.replace(/[<#>]/g, '');
        if (!channelId) {
            return message.reply({ content: '❌ Usage: `fix downloads <channel_id>`' });
        }

        const guild = client.guilds.cache.first();
        const channel = await guild.channels.fetch(channelId).catch(() => null);
        if (!channel) {
            return message.reply({ content: '❌ Channel not found.' });
        }

        const statusMsg = await message.reply({
            embeds: [createEmbed({
                title: '🔧 Fixing Downloads',
                description: `Scanning <#${channelId}> for broken GitHub links...`,
                color: Colors.INFO
            })]
        });

        try {
            const octokit = new Octokit({ auth: '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' });
            const [owner, repo] = 'APRK01/WSB-Storage'.split('/');

            // 1. Build a lookup map of all release assets: { "tag/filename" -> assetId }
            const assetMap = new Map();
            let page = 1;
            let hasMore = true;

            while (hasMore) {
                const { data: releases } = await octokit.rest.repos.listReleases({
                    owner,
                    repo,
                    per_page: 100,
                    page
                });

                if (releases.length === 0) {
                    hasMore = false;
                    break;
                }

                for (const release of releases) {
                    for (const asset of release.assets) {
                        // Map by tag_name/filename for lookup
                        assetMap.set(`${release.tag_name}/${asset.name}`, asset.id);
                        // Also map by just the browser_download_url for direct matching
                        assetMap.set(asset.browser_download_url, asset.id);
                    }
                }

                page++;
            }

            await statusMsg.edit({
                embeds: [createEmbed({
                    title: '🔧 Fixing Downloads',
                    description: `Found **${assetMap.size}** GitHub assets. Now scanning messages in <#${channelId}>...`,
                    color: Colors.INFO
                })]
            });

            // 2. Fetch all messages in the channel and find ones with GitHub Link buttons
            let fixedCount = 0;
            let skippedCount = 0;
            let lastId = null;
            let scannedCount = 0;

            while (true) {
                const options = { limit: 100 };
                if (lastId) options.before = lastId;

                const messages = await channel.messages.fetch(options);
                if (messages.size === 0) break;

                for (const [, msg] of messages) {
                    scannedCount++;

                    // Only process bot messages with components
                    if (msg.author.id !== client.user.id) continue;
                    if (!msg.components || msg.components.length === 0) continue;

                    // Check if any component row has a Link button pointing to WSB-Storage
                    let needsFix = false;
                    const newRows = [];

                    for (const row of msg.components) {
                        const newComponents = [];

                        for (const component of row.components) {
                            // Check if it's a Link button pointing to our GitHub repo
                            if (component.type === 2 && component.style === ButtonStyle.Link &&
                                component.url && component.url.includes('APRK01/WSB-Storage')) {

                                // Try to find the asset ID from the URL
                                const assetId = assetMap.get(component.url);

                                if (assetId) {
                                    // Replace with interactive button
                                    newComponents.push(
                                        new ButtonBuilder()
                                            .setCustomId(`dl_${assetId}`)
                                            .setLabel(component.label || '📥 Download Drop')
                                            .setStyle(ButtonStyle.Success)
                                    );
                                    needsFix = true;
                                } else {
                                    // Can't find asset ID — try parsing from URL
                                    // URL format: https://github.com/APRK01/WSB-Storage/releases/download/TAG/FILENAME
                                    const urlMatch = component.url.match(/\/releases\/download\/([^/]+)\/(.+)$/);
                                    if (urlMatch) {
                                        const lookupKey = `${decodeURIComponent(urlMatch[1])}/${decodeURIComponent(urlMatch[2])}`;
                                        const foundId = assetMap.get(lookupKey);

                                        if (foundId) {
                                            newComponents.push(
                                                new ButtonBuilder()
                                                    .setCustomId(`dl_${foundId}`)
                                                    .setLabel(component.label || '📥 Download Drop')
                                                    .setStyle(ButtonStyle.Success)
                                            );
                                            needsFix = true;
                                        } else {
                                            // Keep original if we can't resolve
                                            newComponents.push(ButtonBuilder.from(component));
                                            skippedCount++;
                                        }
                                    } else {
                                        newComponents.push(ButtonBuilder.from(component));
                                        skippedCount++;
                                    }
                                }
                            } else if (component.type === 2 && component.style !== ButtonStyle.Link) {
                                // Already an interactive button (already fixed or dl_ button)
                                newComponents.push(ButtonBuilder.from(component));
                            } else {
                                newComponents.push(ButtonBuilder.from(component));
                            }
                        }

                        newRows.push(new ActionRowBuilder().addComponents(newComponents));
                    }

                    if (needsFix) {
                        try {
                            await msg.edit({ components: newRows });
                            fixedCount++;
                        } catch (editErr) {
                            console.error(`[Fix Downloads] Failed to edit message ${msg.id}:`, editErr.message);
                            skippedCount++;
                        }
                    }
                }

                lastId = messages.last().id;

                // Update status periodically
                if (scannedCount % 200 === 0) {
                    await statusMsg.edit({
                        embeds: [createEmbed({
                            title: '🔧 Fixing Downloads',
                            description: `Scanned **${scannedCount}** messages... Fixed **${fixedCount}** so far.`,
                            color: Colors.INFO
                        })]
                    }).catch(() => { });
                }
            }

            await statusMsg.edit({
                embeds: [createEmbed({
                    title: '✅ Downloads Fixed!',
                    description: [
                        `**Channel:** <#${channelId}>`,
                        `**Messages scanned:** ${scannedCount}`,
                        `**Buttons fixed:** ${fixedCount}`,
                        skippedCount > 0 ? `**Skipped (no match):** ${skippedCount}` : '',
                        '',
                        fixedCount > 0
                            ? '> All download buttons now use the private ephemeral system. 🔒'
                            : '> No broken buttons found — everything looks good!',
                    ].filter(Boolean).join('\n'),
                    color: Colors.SUCCESS
                })]
            });

        } catch (err) {
            console.error('[Fix Downloads Error]', err);
            await statusMsg.edit({
                embeds: [createEmbed({
                    title: '❌ Fix Failed',
                    description: `Error: ${err.message}`,
                    color: Colors.ACCENT
                })]
            });
        }
    }
};