const cloud = require('wx-server-sdk');

cloud.init({ env: cloud.DYNAMIC_CURRENT_ENV });

const VALID_STATUS = new Set(['draft', 'active', 'hidden']);
const STATUS_ORDER = { draft: 0, hidden: 1, active: 2 };

function mergeSeedStats(items) {
    for (const item of items) {
        item.likes = (item.likes || 0) + (item.likes_seed || 0);
        item.downloads = (item.downloads || 0) + (item.downloads_seed || 0);
    }
}

exports.main = async (event) => {
    try {
        const db = cloud.database();
        const collection = db.collection('worksheets');

        const category = String(event.category || '').trim();
        const status = String(event.status || '').trim();
        const rawStats = event.rawStats === true;

        // Build query condition
        const where = {};
        if (category) where.category = category;
        if (status && VALID_STATUS.has(status)) where.status = status;

        // Query worksheets (cloud DB limit is 100 per call)
        const { data } = await collection
            .where(where)
            .orderBy('sortOrder', 'asc')
            .orderBy('updatedAt', 'desc')
            .limit(100)
            .get();

        // Sort by status order: draft → hidden → active
        data.sort((a, b) => {
            const orderA = STATUS_ORDER[a.status] ?? 99;
            const orderB = STATUS_ORDER[b.status] ?? 99;
            return orderA - orderB;
        });

        // Compute stats for the category (all statuses)
        let allData = data;
        if (status) {
            // If filtered by status, need a separate query for stats
            const statsWhere = {};
            if (category) statsWhere.category = category;
            const { data: allItems } = await collection
                .where(statsWhere)
                .limit(100)
                .get();
            allData = allItems;
        }

        const stats = { total: 0, draft: 0, active: 0, hidden: 0 };
        for (const item of allData) {
            stats.total++;
            if (item.status === 'draft') stats.draft++;
            else if (item.status === 'active') stats.active++;
            else if (item.status === 'hidden') stats.hidden++;
        }

        if (!rawStats) {
            mergeSeedStats(data);
        }

        return {
            success: true,
            data,
            stats,
        };
    } catch (error) {
        return {
            success: false,
            message:
                error instanceof Error ? error.message : '查询 worksheet 失败',
        };
    }
};