const { ChannelType, PermissionFlagsBits } = require('discord.js');
const { Categories } = require('../config');
const { stmts } = require('../database');
const { successEmbed, infoEmbed } = require('../utils/embeds');

module.exports = {
    name: 'create channels',
    async execute(client, message) {
        const guildId = process.env.GUILD_ID;
        const guild = await client.guilds.fetch(guildId);

        await message.reply({ embeds: [infoEmbed('Creating Channels', 'Setting up categories and channels...')] });

        const results = [];

        // Build a role map for permission overwrites
        const roleMap = new Map();
        roleMap.set('everyone', guild.roles.everyone);
        guild.roles.cache.forEach(r => roleMap.set(r.name, r));

        for (const catDef of Categories) {
            // Check if category already exists
            let category = guild.channels.cache.find(
                c => c.type === ChannelType.GuildCategory && c.name === catDef.name
            );

            if (!category) {
                // Build category-level permission overwrites
                const catOverwrites = buildCategoryOverwrites(catDef, roleMap);

                category = await guild.channels.create({
                    name: catDef.name,
                    type: ChannelType.GuildCategory,
                    permissionOverwrites: catOverwrites,
                    reason: 'WSB Setup',
                });
                results.push(`📁 **${catDef.name}** — category created`);
            } else {
                results.push(`📁 **${catDef.name}** — already exists`);
            }

            // Create child channels
            for (const chDef of catDef.channels) {
                const existing = guild.channels.cache.find(
                    c => c.name === chDef.name && c.parentId === category.id
                );
                if (existing) {
                    // Store channel ID in bot state for later reference
                    stmts.setState.run(`channel_${chDef.name}`, existing.id);
                    results.push(`  └ **${chDef.name}** — already exists`);
                    continue;
                }

                const channelType = chDef.type === 'voice'
                    ? ChannelType.GuildVoice
                    : ChannelType.GuildText;

                // Build channel-specific permission overwrites
                const channelOverwrites = buildChannelOverwrites(catDef, chDef, roleMap);

                const channel = await guild.channels.create({
                    name: chDef.name,
                    type: channelType,
                    parent: category.id,
                    permissionOverwrites: channelOverwrites,
                    reason: 'WSB Setup',
                });

                // Store in bot state
                stmts.setState.run(`channel_${chDef.name}`, channel.id);

                results.push(`  └ **${chDef.name}** — created`);
            }
        }

        await message.reply({
            embeds: [successEmbed('Channels Created', results.join('\n'))],
        });
    },
};

/**
 * Build permission overwrites for a category.
 */
function buildCategoryOverwrites(catDef, roleMap) {
    const overrideMap = catDef.permOverrides(roleMap);
    const overwrites = [];

    for (const [roleName, perms] of Object.entries(overrideMap)) {
        const role = roleName === 'everyone' ? roleMap.get('everyone') : roleMap.get(roleName);
        if (!role) continue;

        const allow = [];
        const deny = [];

        if (perms.view === true) allow.push(PermissionFlagsBits.ViewChannel);
        if (perms.view === false) deny.push(PermissionFlagsBits.ViewChannel);
        if (perms.send === true) allow.push(PermissionFlagsBits.SendMessages);
        if (perms.send === false) deny.push(PermissionFlagsBits.SendMessages);

        overwrites.push({ id: role.id || role, allow, deny });
    }

    return overwrites;
}

/**
 * Build channel-specific overwrites, handling readOnly, staffOnly, noEmbeds, and special flags.
 */
function buildChannelOverwrites(catDef, chDef, roleMap) {
    const overrideMap = catDef.permOverrides(roleMap);
    const overwrites = [];

    for (const [roleName, perms] of Object.entries(overrideMap)) {
        const role = roleName === 'everyone' ? roleMap.get('everyone') : roleMap.get(roleName);
        if (!role) continue;

        const allow = [];
        const deny = [];

        // Public channels: @everyone can view (overrides category deny)
        if (chDef.public && roleName === 'everyone') {
            allow.push(PermissionFlagsBits.ViewChannel);
            allow.push(PermissionFlagsBits.ReadMessageHistory);
            allow.push(PermissionFlagsBits.AddReactions);
        } else {
            if (perms.view === true) allow.push(PermissionFlagsBits.ViewChannel);
            if (perms.view === false) deny.push(PermissionFlagsBits.ViewChannel);
        }

        // hideFromVerified: deny view for @@ Verified (verify channel after verification)
        if (chDef.hideFromVerified && roleName === '@@ Verified') {
            // Override: verified users cannot see this channel
            const viewIdx = allow.indexOf(PermissionFlagsBits.ViewChannel);
            if (viewIdx !== -1) allow.splice(viewIdx, 1);
            deny.push(PermissionFlagsBits.ViewChannel);
        }

        if (chDef.ownerOnly) {
            // Only Owner and Co-Owner can send
            if (['@@ Owner', '@@ Co-Owner'].includes(roleName)) {
                allow.push(PermissionFlagsBits.SendMessages);
            } else {
                deny.push(PermissionFlagsBits.SendMessages);
            }
        } else if (chDef.readOnly) {
            // Only Staff and Owner can send in read-only channels
            if (['@@ Staff', '@@ Server Manager', '@@ Owner', '@@ Co-Owner'].includes(roleName)) {
                if (perms.send === true) allow.push(PermissionFlagsBits.SendMessages);
            } else {
                deny.push(PermissionFlagsBits.SendMessages);
            }
        } else if (chDef.staffOnly) {
            // Only Staff and Owner can see/send
            if (['@@ Staff', '@@ Server Manager', '@@ Owner', '@@ Co-Owner'].includes(roleName)) {
                allow.push(PermissionFlagsBits.ViewChannel, PermissionFlagsBits.SendMessages);
            } else {
                deny.push(PermissionFlagsBits.ViewChannel);
            }
        } else if (chDef.special === 'owner-chat') {
            // Only Owner, Co-Owner, and Server Manager can see/send
            if (['@@ Owner', '@@ Co-Owner', '@@ Server Manager'].includes(roleName)) {
                allow.push(PermissionFlagsBits.ViewChannel, PermissionFlagsBits.SendMessages);
            } else {
                deny.push(PermissionFlagsBits.ViewChannel);
            }
        } else if (chDef.special === 'community-content') {
            // Known + Helper + Staff + Owner can send; everyone else view-only
            if (['@@ Known', '@@ Helper', '@@ Staff', '@@ Owner', '@@ Co-Owner'].includes(roleName)) {
                allow.push(PermissionFlagsBits.SendMessages);
            } else {
                if (perms.view === true) {
                    // Can view but not send
                    deny.push(PermissionFlagsBits.SendMessages);
                }
            }
        } else {
            if (perms.send === true) allow.push(PermissionFlagsBits.SendMessages);
            if (perms.send === false) deny.push(PermissionFlagsBits.SendMessages);
        }

        // noEmbeds: block attachments, embeds, and external emojis (text-only channel)
        if (chDef.noEmbeds && !['@@ Staff', '@@ Server Manager', '@@ Owner', '@@ Co-Owner'].includes(roleName)) {
            deny.push(PermissionFlagsBits.AttachFiles);
            deny.push(PermissionFlagsBits.EmbedLinks);
            deny.push(PermissionFlagsBits.UseExternalEmojis);
        }

        // Add reactions for verify and ticket channels
        if (chDef.special === 'verify' || chDef.special === 'ticket') {
            allow.push(PermissionFlagsBits.AddReactions);
            allow.push(PermissionFlagsBits.ReadMessageHistory);
        }

        overwrites.push({ id: role.id || role, allow, deny });
    }

    // For community-content, add Known and Helper overwrites if they aren't in the category overrides
    if (chDef.special === 'community-content') {
        for (const extraRole of ['@@ Known', '@@ Helper']) {
            if (!overrideMap[extraRole]) {
                const role = roleMap.get(extraRole);
                if (role) {
                    overwrites.push({
                        id: role.id,
                        allow: [PermissionFlagsBits.ViewChannel, PermissionFlagsBits.SendMessages],
                        deny: [],
                    });
                }
            }
        }
    }

    return overwrites;
}