// ============ 全局变量 ============
let currentDbName = null;
let pendingImport = null;
let allBackups = [];

// ============ 初始化 ============
async function init() {
    try {
        await window.electronAPI.initDatabase();
        loadDatabases();
        setupDropZone();
        setupEventListeners();
    } catch (err) {
        console.error("初始化失败:", err);
        showToast("初始化失败: " + err.message, "error");
    }
}

// ============ 工具函数 ============
const formatFileSize = (b) => window.electronAPI.formatFileSize(b);
const formatDateDisplay = (d) => window.electronAPI.formatDateDisplay(d);

// ============ 数据库管理 ============
function loadDatabases() {
    const databases = window.electronAPI.listDatabases();
    const listEl = document.getElementById("databaseList");

    if (databases.length === 0) {
        listEl.innerHTML = "<div style=\"color: var(--text-muted); text-align: center; padding: 20px; font-size: 11px;\">暂无数据库</div>";
        return;
    }

    listEl.innerHTML = databases.map(db => `
        <div class="database-item ${db.name === currentDbName ? "active" : ""}" data-name="${db.name}">
            <div class="db-details">
                <div class="db-name">${db.name}</div>
                <div class="db-info">${db.count} 备份 · ${formatFileSize(db.totalSize)}</div>
            </div>
            <div class="db-actions">
                <button class="db-action-btn" title="重命名" onclick="event.stopPropagation(); showRenameDb('${db.name}')"><i class="fa-solid fa-pen"></i></button>
                <button class="db-action-btn delete" title="删除" onclick="event.stopPropagation(); confirmDeleteDb('${db.name}')"><i class="fa-solid fa-trash"></i></button>
            </div>
        </div>
    `).join("");

    listEl.querySelectorAll(".database-item").forEach(item => {
        item.addEventListener("click", () => selectDatabase(item.dataset.name));
    });
}

function selectDatabase(dbName) {
    try {
        window.electronAPI.openDatabase(dbName);
        currentDbName = dbName;

        document.getElementById("noDatabase").style.display = "none";
        document.getElementById("databaseContent").style.display = "flex";
        document.getElementById("searchInput").value = "";

        document.querySelectorAll(".database-item").forEach(item => {
            item.classList.toggle("active", item.dataset.name === dbName);
        });

        loadBackups();
    } catch (err) {
        showToast(err.message, "error");
    }
}

function loadBackups() {
    allBackups = window.electronAPI.getBackups(); // 已按 date_modified 降序排序
    renderBackups(allBackups);
}

function renderBackups(backups) {
    const listEl = document.getElementById("backupList");
    document.getElementById("backupCount").textContent = `${backups.length} 个备份`;

    if (backups.length === 0) {
        listEl.innerHTML = "";
        return;
    }

    const icons = { "zip": "fa-file-zipper", "rar": "fa-file-zipper", "7z": "fa-file-zipper", "tar": "fa-file-archive", "gz": "fa-file-archive" };

    listEl.innerHTML = backups.map(b => `
        <div class="backup-item" data-id="${b.id}" data-search="${b.filename.toLowerCase()} ${(b.tag || "").toLowerCase()}">
            <div class="backup-icon"><i class="fa-solid ${icons[b.archive_type] || "fa-file"}"></i></div>
            <div class="backup-details">
                <div class="backup-name">${b.filename}</div>
                <div class="backup-meta">
                    <span><i class="fa-regular fa-calendar"></i> ${formatDateDisplay(b.date_modified)}</span>
                    <span><i class="fa-regular fa-file"></i> ${formatFileSize(b.file_size)}</span>
                    <span class="backup-tag ${b.tag ? "" : "empty"}" onclick="showEditTag(${b.id}, '${escapeHtml(b.tag || "")}')">
                        <i class="fa-solid fa-tag"></i> ${b.tag || "标签"}
                    </span>
                </div>
            </div>
            <div class="backup-actions">
                <button class="backup-action-btn export" title="导出" onclick="exportBackup(${b.id})"><i class="fa-solid fa-download"></i></button>
                <button class="backup-action-btn delete" title="删除" onclick="confirmDeleteBackup(${b.id})"><i class="fa-solid fa-trash"></i></button>
            </div>
        </div>
    `).join("");
}

function filterBackups() {
    const query = document.getElementById("searchInput").value.toLowerCase().trim();

    if (!query) {
        renderBackups(allBackups);
        return;
    }

    const filtered = allBackups.filter(b =>
        b.filename.toLowerCase().includes(query) ||
        (b.tag && b.tag.toLowerCase().includes(query)) ||
        b.date_modified.includes(query)
    );

    renderBackups(filtered);
}

function escapeHtml(str) {
    return str ? str.replace(/'/g, "\\'").replace(/"/g, "\\\"") : "";
}

// ============ 拖拽处理 ============
function setupDropZone() {
    const dropZone = document.getElementById("dropZone");

    ["dragenter", "dragover", "dragleave", "drop"].forEach(e => {
        dropZone.addEventListener(e, ev => { ev.preventDefault(); ev.stopPropagation(); });
        document.body.addEventListener(e, ev => { ev.preventDefault(); ev.stopPropagation(); });
    });

    ["dragenter", "dragover"].forEach(e => dropZone.addEventListener(e, () => dropZone.classList.add("drag-over")));
    ["dragleave", "drop"].forEach(e => dropZone.addEventListener(e, () => dropZone.classList.remove("drag-over")));

    dropZone.addEventListener("drop", handleDrop);
}

async function handleDrop(e) {
    if (!currentDbName) { showToast("请先选择数据库", "warning"); return; }
    const files = e.dataTransfer.files;
    if (files.length === 0) return;
    await processImport(files[0].path);
}

async function processImport(filePath) {
    showLoading("处理中...");

    try {
        const stats = window.electronAPI.getFileStats(filePath);
        if (!stats) throw new Error("无法读取文件");

        const originalName = window.electronAPI.pathBasename(filePath);
        let dateModified, archiveType, sourcePath = filePath, tempFile = null;

        if (stats.isDirectory) {
            showLoading("压缩文件夹...");
            const latestTime = window.electronAPI.getLatestModifiedTime(filePath);
            dateModified = window.electronAPI.formatDateModified(latestTime);
            archiveType = "zip";

            const dataPath = await window.electronAPI.getDataPath();
            const tempDir = window.electronAPI.pathJoin(dataPath, "temp");
            window.electronAPI.ensureDir(tempDir);
            tempFile = window.electronAPI.pathJoin(tempDir, `temp_${Date.now()}.zip`);
            await window.electronAPI.compressFolder(filePath, tempFile);
            sourcePath = tempFile;
        } else {
            if (!window.electronAPI.isSupportedArchive(filePath)) {
                throw new Error("不支持的格式");
            }
            dateModified = window.electronAPI.formatDateModified(new Date(stats.mtime));
            archiveType = window.electronAPI.getArchiveType(filePath);
        }

        const targetFilename = window.electronAPI.generateBackupFilename(currentDbName, dateModified, archiveType);

        if (!window.electronAPI.isNameMatching(originalName, currentDbName)) {
            hideLoading();
            pendingImport = { sourcePath, originalName, dateModified, archiveType, targetFilename, tempFile };
            showNameMismatchModal(originalName, currentDbName, targetFilename);
            return;
        }

        await performImport(sourcePath, originalName, dateModified, archiveType, targetFilename, tempFile);
    } catch (err) {
        hideLoading();
        showToast(err.message, "error");
    }
}

async function performImport(sourcePath, originalName, dateModified, archiveType, targetFilename, tempFile) {
    showLoading("导入中...");

    try {
        const storagePath = window.electronAPI.getCurrentStoragePath();
        const targetPath = window.electronAPI.pathJoin(storagePath, targetFilename);

        const existing = window.electronAPI.findByDateModified(dateModified);
        if (existing) {
            window.electronAPI.deleteFile(window.electronAPI.pathJoin(storagePath, existing.filename));
        }

        await window.electronAPI.copyArchive(sourcePath, targetPath);
        const targetStats = window.electronAPI.getFileStats(targetPath);

        window.electronAPI.upsertBackup({
            filename: targetFilename,
            original_name: originalName,
            date_modified: dateModified,
            archive_type: archiveType,
            file_size: targetStats.size
        });

        if (tempFile) window.electronAPI.deleteFile(tempFile);

        hideLoading();
        showToast("导入成功", "success");
        loadBackups();
        loadDatabases();
    } catch {
        hideLoading();
        showToast("导入失败", "error");
    }
}

// ============ 模态框 ============
function showModal(id) { document.getElementById(id).classList.add("show"); }
function closeModal(id) {
    document.getElementById(id).classList.remove("show");
    if (id === "nameMismatchModal" && pendingImport?.tempFile) {
        window.electronAPI.deleteFile(pendingImport.tempFile);
        pendingImport = null;
    }
}

function showNewDbModal() {
    document.getElementById("dbModalTitle").textContent = "新建数据库";
    document.getElementById("dbName").value = "";
    document.getElementById("btnConfirmDb").onclick = confirmCreateDb;
    showModal("dbModal");
    document.getElementById("dbName").focus();
}

function confirmCreateDb() {
    const name = document.getElementById("dbName").value.trim();
    if (!name) { showToast("请输入名称", "warning"); return; }
    if (!/^[\w\u4e00-\u9fa5]+$/.test(name)) { showToast("名称包含非法字符", "warning"); return; }

    try {
        window.electronAPI.createDatabase(name);
        closeModal("dbModal");
        showToast("创建成功", "success");
        loadDatabases();
        selectDatabase(name);
    } catch (err) {
        showToast(err.message, "error");
    }
}

function showRenameDb(dbName) {
    document.getElementById("dbModalTitle").textContent = "重命名";
    document.getElementById("dbName").value = dbName;
    document.getElementById("btnConfirmDb").onclick = () => confirmRenameDb(dbName);
    showModal("dbModal");
    document.getElementById("dbName").focus();
    document.getElementById("dbName").select();
}

function confirmRenameDb(oldName) {
    const newName = document.getElementById("dbName").value.trim();
    if (!newName) { showToast("请输入名称", "warning"); return; }
    if (newName === oldName) { closeModal("dbModal"); return; }
    if (!/^[\w\u4e00-\u9fa5]+$/.test(newName)) { showToast("名称包含非法字符", "warning"); return; }

    try {
        showLoading("重命名中...");
        window.electronAPI.renameDatabase(oldName, newName);
        if (currentDbName === oldName) {
            currentDbName = newName;
            window.electronAPI.openDatabase(newName);
        }
        hideLoading();
        closeModal("dbModal");
        showToast("重命名成功", "success");
        loadDatabases();
        loadBackups();
    } catch (err) {
        hideLoading();
        showToast(err.message, "error");
    }
}

function confirmDeleteDb(dbName) {
    showConfirm("删除数据库", `确定删除 "${dbName}"？所有备份将被删除！`, () => {
        try {
            window.electronAPI.deleteDatabase(dbName);
            if (currentDbName === dbName) {
                currentDbName = null;
                document.getElementById("noDatabase").style.display = "flex";
                document.getElementById("databaseContent").style.display = "none";
            }
            showToast("已删除", "success");
            loadDatabases();
        } catch (err) {
            showToast(err.message, "error");
        }
    });
}

function showConfirm(title, message, onConfirm) {
    document.getElementById("confirmTitle").textContent = title;
    document.getElementById("confirmMessage").textContent = message;
    document.getElementById("btnConfirmAction").onclick = () => { closeModal("confirmModal"); onConfirm(); };
    showModal("confirmModal");
}

function showNameMismatchModal(sourceName, dbName, newFileName) {
    document.getElementById("sourceFileName").textContent = sourceName;
    document.getElementById("targetDbName").textContent = dbName;
    document.getElementById("newFileName").textContent = newFileName;
    showModal("nameMismatchModal");
}

async function confirmMismatchImport() {
    closeModal("nameMismatchModal");
    if (pendingImport) {
        const { sourcePath, originalName, dateModified, archiveType, targetFilename, tempFile } = pendingImport;
        pendingImport = null;
        await performImport(sourcePath, originalName, dateModified, archiveType, targetFilename, tempFile);
    }
}

// ============ 标签编辑 ============
let editingTagId = null;

function showEditTag(id, currentTag) {
    editingTagId = id;
    document.getElementById("tagInput").value = currentTag || "";
    showModal("tagModal");
    document.getElementById("tagInput").focus();
}

function saveTag() {
    const tag = document.getElementById("tagInput").value.trim();
    try {
        window.electronAPI.updateTag(editingTagId, tag);
        closeModal("tagModal");
        showToast("已保存", "success");
        loadBackups();
    } catch (err) {
        showToast(err.message, "error");
    }
}

function clearTag() {
    try {
        window.electronAPI.updateTag(editingTagId, null);
        closeModal("tagModal");
        showToast("已清除", "success");
        loadBackups();
    } catch (err) {
        showToast(err.message, "error");
    }
}

// ============ 导出和删除 ============
async function exportBackup(id) {
    const backup = allBackups.find(b => b.id === id);
    if (!backup) { showToast("不存在", "error"); return; }

    const exportDir = await window.electronAPI.selectExportDir();
    if (!exportDir) return;

    const storagePath = window.electronAPI.getCurrentStoragePath();
    const sourcePath = window.electronAPI.pathJoin(storagePath, backup.filename);
    const targetPath = window.electronAPI.pathJoin(exportDir, backup.filename);

    try {
        showLoading("导出中...");
        await window.electronAPI.copyArchive(sourcePath, targetPath);
        hideLoading();
        showToast("导出成功", "success");
        window.electronAPI.showInFolder(targetPath);
    } catch {
        hideLoading();
        showToast("导出失败", "error");
    }
}

function confirmDeleteBackup(id) {
    showConfirm("删除备份", "确定删除？不可恢复！", () => {
        try {
            window.electronAPI.deleteBackup(id);
            showToast("已删除", "success");
            loadBackups();
            loadDatabases();
        } catch (err) {
            showToast(err.message, "error");
        }
    });
}

// ============ 工具函数 ============
function showToast(message, type = "success") {
    const toast = document.getElementById("toast");
    const icons = { success: "fa-check", error: "fa-xmark", warning: "fa-exclamation" };

    toast.className = "toast " + type;
    document.getElementById("toastIcon").className = "toast-icon fa-solid " + (icons[type] || "fa-check");
    document.getElementById("toastMessage").textContent = message;
    toast.classList.add("show");

    setTimeout(() => toast.classList.remove("show"), 2500);
}

function showLoading(text = "处理中...") {
    document.getElementById("loadingText").textContent = text;
    document.getElementById("loadingOverlay").classList.add("show");
}

function hideLoading() {
    document.getElementById("loadingOverlay").classList.remove("show");
}

// ============ 事件监听 ============
function setupEventListeners() {
    document.getElementById("btnConfirmImport").addEventListener("click", confirmMismatchImport);
    document.getElementById("btnConfirmTag").addEventListener("click", saveTag);
    document.getElementById("btnClearTag").addEventListener("click", clearTag);

    document.querySelectorAll(".modal-overlay").forEach(overlay => {
        overlay.addEventListener("click", e => {
            const modal = e.target.closest(".modal");
            if (modal) closeModal(modal.id);
        });
    });

    document.addEventListener("keydown", e => {
        if (e.key === "Escape") {
            const openModal = document.querySelector(".modal.show");
            if (openModal) closeModal(openModal.id);
        }
    });

    document.getElementById("dbName").addEventListener("keydown", e => {
        if (e.key === "Enter") document.getElementById("btnConfirmDb").click();
    });

    document.getElementById("tagInput").addEventListener("keydown", e => {
        if (e.key === "Enter") saveTag();
    });
}

// 初始化
document.addEventListener("DOMContentLoaded", init);

// 暴露全局函数
window.showNewDbModal = showNewDbModal;
window.showRenameDb = showRenameDb;
window.confirmDeleteDb = confirmDeleteDb;
window.showEditTag = showEditTag;
window.exportBackup = exportBackup;
window.confirmDeleteBackup = confirmDeleteBackup;
window.closeModal = closeModal;
window.filterBackups = filterBackups;