const db = require("../plugin/DataBase/db");

function normalizeClientType(value) {
    return String(value || "").trim().toLowerCase();
}

function parseVersionParts(version) {
    return String(version || "")
        .trim()
        .replace(/^[vV]/, "")
        .split(/[.+_-]/)
        .map(part => {
            const n = Number.parseInt(part, 10);
            return Number.isFinite(n) ? n : 0;
        });
}

function compareVersionName(a, b) {
    const left = parseVersionParts(a);
    const right = parseVersionParts(b);
    const len = Math.max(left.length, right.length);
    for (let i = 0; i < len; i++) {
        const diff = (left[i] || 0) - (right[i] || 0);
        if (diff !== 0) return diff > 0 ? 1 : -1;
    }
    return 0;
}

function isVersionNewer(remote, local) {
    const remoteCode = Number(remote.version_code);
    const localCode = Number(local.version_code);
    if (Number.isFinite(remoteCode) && remoteCode > 0 && Number.isFinite(localCode) && localCode > 0)
        return remoteCode > localCode;
    return compareVersionName(remote.version_name, local.version_name) > 0;
}

function toUniAppPayload(row) {
    return {
        describe: row.release_notes_html || row.release_notes || "",
        edition_url: row.download_url,
        edition_force: Number(row.force_update) || 0,
        package_type: Number(row.package_type) || 0,
        edition_issue: Number(row.is_active) === 0 ? 0 : 1,
        edition_number: Number(row.version_code) || 0,
        edition_name: row.version_name,
        edition_silence: Number(row.silent_update) || 0,
        log: row.release_notes || ""
    };
}

function toPublicPayload(row, localVersion = {}) {
    if (!row) {
        return {
            has_update: false,
            update_available: false
        };
    }
    const remote = {
        version_name: row.version_name,
        version_code: Number(row.version_code) || 0
    };
    const local = {
        version_name: localVersion.version_name,
        version_code: localVersion.version_code
    };
    const hasUpdate = isVersionNewer(remote, local);
    const payload = {
        has_update: hasUpdate,
        update_available: hasUpdate,
        client_type: row.client_type,
        title: row.title || "",
        version: row.version_name,
        version_name: row.version_name,
        version_code: Number(row.version_code) || 0,
        download_url: row.download_url,
        sha256: row.sha256 || "",
        file_size: Number(row.file_size) || 0,
        package_type: Number(row.package_type) || 0,
        force_update: Number(row.force_update) || 0,
        silent_update: Number(row.silent_update) || 0,
        release_notes: row.release_notes || "",
        release_notes_html: row.release_notes_html || "",
        min_supported_version: row.min_supported_version || ""
    };
    if (normalizeClientType(row.client_type) === "android") {
        Object.assign(payload, toUniAppPayload(row), {
            uniapp: toUniAppPayload(row)
        });
    }
    return payload;
}

async function getLatestVersion(clientType) {
    const normalized = normalizeClientType(clientType);
    const rows = await db.query(`
        SELECT id, client_type, version_name, version_code, title, download_url,
               sha256, file_size, package_type, force_update, silent_update,
               is_active, release_notes, release_notes_html, min_supported_version,
               sort_order, created_at, updated_at
        FROM download_version
        WHERE client_type = ? AND is_active = 1
        ORDER BY version_code DESC, sort_order ASC, id DESC
        LIMIT 1
    `, [normalized]);
    return rows && rows[0] ? rows[0] : null;
}

async function listVersions(clientType = "") {
    const normalized = normalizeClientType(clientType);
    if (normalized) {
        return await db.query(`
            SELECT id, client_type, version_name, version_code, title, download_url,
                   sha256, file_size, package_type, force_update, silent_update,
                   is_active, release_notes, release_notes_html, min_supported_version,
                   sort_order, created_at, updated_at
            FROM download_version
            WHERE client_type = ?
            ORDER BY client_type ASC, version_code DESC, sort_order ASC, id DESC
        `, [normalized]);
    }
    return await db.query(`
        SELECT id, client_type, version_name, version_code, title, download_url,
               sha256, file_size, package_type, force_update, silent_update,
               is_active, release_notes, release_notes_html, min_supported_version,
               sort_order, created_at, updated_at
        FROM download_version
        ORDER BY client_type ASC, version_code DESC, sort_order ASC, id DESC
    `);
}

async function saveVersion(payload) {
    const now = Date.now();
    const data = {
        client_type: normalizeClientType(payload.client_type),
        version_name: String(payload.version_name || payload.version || "").trim(),
        version_code: Number(payload.version_code) || 0,
        title: String(payload.title || "").trim(),
        download_url: String(payload.download_url || "").trim(),
        sha256: String(payload.sha256 || "").trim().toLowerCase(),
        file_size: Number(payload.file_size) || 0,
        package_type: Number(payload.package_type) || 0,
        force_update: Number(payload.force_update) === 1 ? 1 : 0,
        silent_update: Number(payload.silent_update) === 1 ? 1 : 0,
        is_active: Number(payload.is_active) === 0 ? 0 : 1,
        release_notes: payload.release_notes || "",
        release_notes_html: payload.release_notes_html || "",
        min_supported_version: String(payload.min_supported_version || "").trim(),
        sort_order: Number(payload.sort_order) || 0
    };

    if (payload.id) {
        const result = await db.query(`
            UPDATE download_version SET
                client_type = ?, version_name = ?, version_code = ?, title = ?,
                download_url = ?, sha256 = ?, file_size = ?, package_type = ?,
                force_update = ?, silent_update = ?, is_active = ?,
                release_notes = ?, release_notes_html = ?, min_supported_version = ?,
                sort_order = ?, updated_at = ?
            WHERE id = ?
        `, [
            data.client_type, data.version_name, data.version_code, data.title,
            data.download_url, data.sha256, data.file_size, data.package_type,
            data.force_update, data.silent_update, data.is_active,
            data.release_notes, data.release_notes_html, data.min_supported_version,
            data.sort_order, now, payload.id
        ]);
        return { id: payload.id, result };
    }

    const result = await db.query(`
        INSERT INTO download_version
            (client_type, version_name, version_code, title, download_url,
             sha256, file_size, package_type, force_update, silent_update,
             is_active, release_notes, release_notes_html, min_supported_version,
             sort_order, created_at, updated_at)
        VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
    `, [
        data.client_type, data.version_name, data.version_code, data.title,
        data.download_url, data.sha256, data.file_size, data.package_type,
        data.force_update, data.silent_update, data.is_active,
        data.release_notes, data.release_notes_html, data.min_supported_version,
        data.sort_order, now, now
    ]);
    return { id: result && result.insertId, result };
}

async function deleteVersion(id) {
    return await db.query("DELETE FROM download_version WHERE id = ?", [id]);
}

module.exports = {
    getLatestVersion,
    listVersions,
    saveVersion,
    deleteVersion,
    toPublicPayload,
    toUniAppPayload,
    normalizeClientType
};