// Devlog-Endpoint: nimmt Discord-Webhook-kompatible Payloads von tools/devlog.py
// entgegen (JSON oder Multipart mit Bildern), postet ein gebrandetes Embed als
// Bot in den Devlog-Kanal und archiviert Text + Bilder direkt in SQLite.
//
// devlog.py bleibt unverändert — in tools/.devlog_webhook steht einfach
// https://bot.d4rkst3r.de/webhooks/devlog/<DEVLOG_POST_SECRET> statt der Discord-URL.
import crypto from 'node:crypto';
import { writeFile } from 'node:fs/promises';
import { join } from 'node:path';
import { AttachmentBuilder, EmbedBuilder } from 'discord.js';
import { config } from '../config.js';
import { saveDevlog } from '../db.js';
import { devlogChannelId } from '../runtime-settings.js';
import { imagesDir } from '../bot/devlog-archive.js';

const BRAND_YELLOW = 0xf5c518;
const MAX_IMAGES = 4;

/** Secret timing-safe vergleichen */
function secretOk(given) {
    const a = Buffer.from(String(given ?? ''));
    const b = Buffer.from(config.devlogPostSecret);
    return a.length === b.length && crypto.timingSafeEqual(a, b);
}

/** Multipart-Request einlesen → { payload, files: [{name, buffer}] } */
async function readMultipart(request) {
    let payload = {};
    const files = [];
    for await (const part of request.parts()) {
        if (part.type === 'file') {
            if (files.length < MAX_IMAGES && /\.(png|jpe?g|gif|webp)$/i.test(part.filename ?? '')) {
                files.push({ name: part.filename, buffer: await part.toBuffer() });
            } else {
                await part.toBuffer(); // Stream leeren, sonst hängt der Request
            }
        } else if (part.fieldname === 'payload_json') {
            // @fastify/multipart parst Felder mit Content-Type application/json bereits selbst
            payload = typeof part.value === 'string' ? JSON.parse(part.value) : part.value;
        }
    }
    return { payload, files };
}

export function registerDevlogEndpoint(app, client) {
    app.post('/webhooks/devlog/:secret', async (request, reply) => {
        if (!secretOk(request.params.secret)) {
            request.log.warn('Devlog-Post mit ungültigem Secret abgelehnt');
            return reply.code(401).send({ error: 'invalid secret' });
        }

        // Payload lesen: Multipart (mit Bildern) oder plain JSON
        let payload;
        let files = [];
        if (request.isMultipart()) {
            ({ payload, files } = await readMultipart(request));
        } else {
            payload = request.body ?? {};
        }

        const srcEmbed = payload.embeds?.[0] ?? {};
        const title = srcEmbed.title ?? 'Devlog';
        const description = srcEmbed.description ?? payload.content ?? '';
        if (!description.trim()) {
            return reply.code(400).send({ error: 'empty devlog' });
        }

        const targetChannel = devlogChannelId();
        if (!targetChannel) {
            return reply.code(500).send({ error: 'no devlog channel configured' });
        }
        const channel = await client.channels.fetch(targetChannel);
        if (!channel?.isTextBased()) {
            return reply.code(500).send({ error: 'devlog channel not found' });
        }

        // Gebrandetes Embed; bis zu 4 Bilder als Grid (Discord gruppiert Embeds mit gleicher URL)
        const groupUrl = srcEmbed.url || `${config.publicUrl}/devlogs`;
        const attachments = files.map(
            (f, i) => new AttachmentBuilder(f.buffer, { name: `devlog_${i}.${f.name.split('.').pop().toLowerCase()}` })
        );
        const embeds = [
            new EmbedBuilder()
                .setColor(BRAND_YELLOW)
                .setTitle(title)
                .setURL(groupUrl)
                .setDescription(description)
                .setFooter({ text: 'D4RKST3R // DEVLOG' })
                .setTimestamp(),
        ];
        attachments.forEach((att, i) => {
            if (i === 0) {
                embeds[0].setImage(`attachment://${att.name}`);
            } else {
                embeds.push(
                    new EmbedBuilder().setURL(groupUrl).setImage(`attachment://${att.name}`)
                );
            }
        });

        const message = await channel.send({ embeds, files: attachments });

        // Direkt archivieren (der Live-Listener ignoriert eigene Bot-Posts bewusst)
        const imageFiles = [];
        for (const [i, f] of files.entries()) {
            const file = `${message.id}_${i}.${f.name.split('.').pop().toLowerCase()}`;
            await writeFile(join(imagesDir, file), f.buffer);
            imageFiles.push(file);
        }
        saveDevlog({
            message_id: message.id,
            channel_id: message.channelId,
            content: `${title}\n\n${description}`,
            author_name: 'D4RKST3R // DEVLOG',
            posted_at: message.createdAt.toISOString(),
            images: JSON.stringify(imageFiles),
        });

        request.log.info(`Devlog gepostet + archiviert (${message.id}, ${imageFiles.length} Bilder)`);
        return { ok: true, message_id: message.id, images: imageFiles.length };
    });
}