#!/usr/bin/env node
/**
 * Cleanup helper:
 * - Removes Photo docs whose main/variant paths are not WebP.
 * - Deletes non-WebP files in uploads.
 * - Optionally deletes orphaned WebP files (not referenced by any Photo) when DELETE_ORPHANS=1.
 *
 * Dry-run by default. Set APPLY=1 to make changes.
 */
const fs = require('fs');
const path = require('path');
const mongoose = require('mongoose');
const Photo = require('../models/photo');

const MONGO_URI = process.env.MONGO_URI || 'mongodb://localhost:27017/photogallery';
const APPLY = process.env.APPLY === '1';
const DELETE_ORPHANS = process.env.DELETE_ORPHANS === '1';
const UPLOAD_DIR = path.join(__dirname, '..', 'uploads');

const isWebp = (p) => /\.webp$/i.test(p || '');

async function main() {
    await mongoose.connect(MONGO_URI);
    console.log(`Connected to Mongo: ${MONGO_URI}`);

    // Find docs with non-webp main or variants
    const nonWebpDocs = await Photo.find({
        $or: [
            { path: { $not: /\.webp$/i } },
            { 'variants.medium': { $exists: true, $not: /\.webp$/i } },
            { 'variants.thumb': { $exists: true, $not: /\.webp$/i } },
        ]
    }).select('_id path variants filename');

    // Build referenced file set from remaining docs
    const allDocs = await Photo.find().select('path variants');
    const referenced = new Set();
    for (const doc of allDocs) {
        if (doc.path) referenced.add(doc.path);
        if (doc.variants?.medium) referenced.add(doc.variants.medium);
        if (doc.variants?.thumb) referenced.add(doc.variants.thumb);
    }

    // Scan uploads directory
    const filesOnDisk = [];
    const walk = (dir) => {
        for (const entry of fs.readdirSync(dir)) {
            const full = path.join(dir, entry);
            const stat = fs.statSync(full);
            if (stat.isDirectory()) walk(full);
            else filesOnDisk.push(full);
        }
    };
    walk(UPLOAD_DIR);

    const nonWebpFiles = filesOnDisk.filter(f => !isWebp(f));
    const orphans = filesOnDisk
        .filter(f => isWebp(f))
        .filter(f => !referenced.has(path.relative(path.join(__dirname, '..'), f).replace(/\\/g, '/')));

    console.log(`Found ${nonWebpDocs.length} photo docs with non-WebP paths/variants.`);
    console.log(`Found ${nonWebpFiles.length} non-WebP files on disk.`);
    console.log(`Found ${orphans.length} orphaned WebP files${DELETE_ORPHANS ? ' (will delete if APPLY=1)' : ''}.`);

    if (!APPLY) {
        console.log('Dry run (set APPLY=1 to apply changes).');
        await mongoose.disconnect();
        return;
    }

    if (nonWebpDocs.length) {
        const ids = nonWebpDocs.map(d => d._id);
        await Photo.deleteMany({ _id: { $in: ids } });
        console.log(`Deleted ${ids.length} photo docs with non-WebP paths/variants.`);
    }

    for (const file of nonWebpFiles) {
        try {
            fs.unlinkSync(file);
        } catch (err) {
            console.error('Failed to delete', file, err.message);
        }
    }
    console.log(`Deleted ${nonWebpFiles.length} non-WebP files.`);

    if (DELETE_ORPHANS && orphans.length) {
        for (const file of orphans) {
            try {
                fs.unlinkSync(file);
            } catch (err) {
                console.error('Failed to delete orphan', file, err.message);
            }
        }
        console.log(`Deleted ${orphans.length} orphaned WebP files.`);
    }

    await mongoose.disconnect();
    console.log('Cleanup complete.');
}

main().catch(err => {
    console.error(err);
    process.exit(1);
});