class WebDAVModule {
    constructor() {
        this.commands = {};
        this.terminal = null;
        this.config = null;  // { url, username, password }
        this._browsingPath = '/';
        this._STORAGE_KEY = 'webx11_webdav_config';
        // Auto-discover space name from page URL
        this._spaceName = this._detectSpaceName();
        this._autoConfigured = false;
        this._loadConfig();
    }

    _detectSpaceName() {
        try {
            const path = window.location.pathname;
            // /spaces/chatstudio/newos4/ → chatstudio
            const parts = path.split('/').filter(p => p);
            const spacesIdx = parts.indexOf('spaces');
            if (spacesIdx >= 0 && spacesIdx + 1 < parts.length) {
                return parts[spacesIdx + 1];
            }
        } catch (e) {}
        return '';
    }

    requirements() {
        const cfg = localStorage.getItem('webx11_webdav_config');
        if (!cfg) return { met: false, missing: ['WebDAV endpoint not configured. Use webdav-config to set it up.'] };
        try {
            const parsed = JSON.parse(cfg);
            if (!parsed.url) return { met: false, missing: ['WebDAV URL not set'] };
            return { met: true, missing: [] };
        } catch (e) {
            return { met: false, missing: ['WebDAV config corrupted'] };
        }
    }

    getHelpInfo() {
        return {
            'webdav-config': 'webdav-config [url user pass] — Configure WebDAV. No args = auto-detect from current page URL',
            'webdav-status': 'Show current WebDAV configuration status',
            'webdav-ls': 'List files/directories on the WebDAV remote',
            'webdav-push': 'Upload a VFS file to WebDAV',
            'webdav-pull': 'Download a WebDAV file to VFS',
            'webdav-backup': 'Backup entire VFS to WebDAV as a dated JSON snapshot',
            'webdav-restore': 'Restore VFS from a WebDAV backup file',
            'webdav-backup-list': 'List available backup files on WebDAV',
            'webdav-explorer': 'webdav-explorer [path] — Interactive remote file browser',
        };
    }
    
    _loadConfig() {
        try {
            const saved = localStorage.getItem(this._STORAGE_KEY);
            if (saved) {
                this.config = JSON.parse(saved);
                // Try to get password from SecretVault
                if (window.webx11_secretVault && this.config && this.config.username) {
                    const encryptedPass = window.webx11_secretVault.decrypt('webdav_pass_' + this.config.username);
                    if (encryptedPass !== null && encryptedPass !== undefined) {
                        this.config.password = encryptedPass;
                    }
                }
            }
        } catch (e) { /* ignore */ }
    }
    
    _saveConfig() {
        try {
            if (this.config) {
                const toStore = {
                    url: this.config.url,
                    username: this.config.username
                };
                // Try SecretVault for encrypted password storage
                if (window.webx11_secretVault && this.config.password) {
                    window.webx11_secretVault.encrypt('webdav_pass_' + this.config.username, this.config.password);
                    // Also store space token
                    if (this._spaceName) {
                        window.webx11_secretVault.encrypt('webdav_token_' + this._spaceName, this.config.password);
                    }
                }
                // Also store in localStorage for backward compat (SecretVault decrypts later)
                // Store only url and username hint in plaintext lS, encrypted password handled above
                localStorage.setItem(this._STORAGE_KEY, JSON.stringify(toStore));
            } else {
                localStorage.removeItem(this._STORAGE_KEY);
            }
        } catch (e) { console.error('WebDAV config save error:', e); }
    }
    
    _getAuthHeader() {
        if (!this.config || !this.config.password) return {};
        const token = btoa(this.config.username + ':' + this.config.password);
        return { 'Authorization': 'Basic ' + token };
    }
    
    async _webdavRequest(method, path, options = {}) {
        if (!this.config || !this.config.url) {
            throw new Error('WebDAV not configured. Use webdav-config first.');
        }
        const baseUrl = this.config.url.replace(/\/+$/, '');
        const urlPath = path ? (path.startsWith('/') ? path : '/' + path) : '/';
        const url = baseUrl + urlPath;
        
        const headers = {
            ...this._getAuthHeader(),
            ...(options.headers || {})
        };
        
        const fetchOpts = {
            method: method,
            headers: headers,
            body: options.body || undefined
        };
        
        const response = await fetch(url, fetchOpts);
        return response;
    }
    
    async _listDir(path) {
        // Try PROPFIND first (works with WebDAV servers), fallback to nginx autoindex
        try {
            const response = await this._webdavRequest('PROPFIND', path, {
                headers: { 'Depth': '1' }
            });
            if (response.ok) {
                const text = await response.text();
                return this._parsePropfind(text);
            }
        } catch (e) { /* PROPFIND failed, try autoindex */ }
        // Fallback: use nginx __list__ endpoint
        return this._listDirViaAutoIndex(path);
    }

    async _listDirViaAutoIndex(path) {
        const baseUrl = this.config.url.replace(/\/+$/, '');
        const urlPath = path ? (path.startsWith('/') ? path : '/' + path) : '/';
        // Use __list__ for directory listing
        const listUrl = baseUrl.replace(/\/spaces\/([^/]+)\//, '/spaces/$1/__list__/') + urlPath.replace(/^\//, '');
        try {
            const resp = await fetch(listUrl, { method: 'GET' });
            if (!resp.ok) throw new Error('Autoindex failed: HTTP ' + resp.status);
            const html = await resp.text();
            return this._parseAutoindex(html);
        } catch (e) {
            throw new Error('Cannot list directory: ' + e.message);
        }
    }

    _parseAutoindex(html) {
        const entries = [];
        // Parse nginx autoindex HTML format
        const linkRegex = /<a href="([^"]+)">([^<]+)<\/a>\s+(\d{2}-[A-Za-z]{3}-\d{4}\s+\d{2}:\d{2})\s+([\d\w.-]+)/g;
        let match;
        while ((match = linkRegex.exec(html)) !== null) {
            const href = match[1];
            const name = match[2].replace(/\/$/, '');
            const sizeStr = match[4];
            if (name === '..' || name === '../') continue;
            if (name === '__list__') continue;
            const isDir = href.endsWith('/');
            let size = 0;
            if (!isDir && sizeStr !== '-') {
                size = parseInt(sizeStr) || 0;
            }
            entries.push({
                name: name,
                type: isDir ? 'dir' : 'file',
                size: size,
                href: href
            });
        }
        // Fallback: if regex failed, try simpler parse
        if (entries.length === 0) {
            const simpleRegex = /<a href="([^"]+)">/g;
            const names = [];
            while ((match = simpleRegex.exec(html)) !== null) {
                const href = match[1];
                if (href === '../' || href === '/' || href === './') continue;
                if (href.startsWith('?')) continue;
                names.push(href);
            }
            for (const href of names) {
                const isDir = href.endsWith('/');
                entries.push({
                    name: decodeURIComponent(href.replace(/\/$/, '').split('/').pop() || href),
                    type: isDir ? 'dir' : 'file',
                    size: 0,
                    href: href
                });
            }
        }
        return entries;
    }
    
    _parsePropfind(xml) {
        const parser = new DOMParser();
        const doc = parser.parseFromString(xml, 'text/xml');
        const responses = doc.querySelectorAll('D\\:response, response');
        const entries = [];
        responses.forEach((resp) => {
            const href = (resp.querySelector('D\\:href, href') || {}).textContent || '';
            const isDir = !!((resp.querySelector('D\\:collection, collection') || {}).textContent);
            const getContentLength = (resp.querySelector('D\\:getcontentlength, getcontentlength, lp1\\:getcontentlength') || {}).textContent;
            const size = getContentLength ? parseInt(getContentLength) : 0;
            const displayName = href.split('/').filter(Boolean).pop() || '/';
            if (displayName) {
                entries.push({
                    name: decodeURIComponent(displayName),
                    type: isDir ? 'dir' : 'file',
                    size: size,
                    href: href
                });
            }
        });
        // Remove the root entry (same as first child's dir)
        return entries.filter((e, i) => i > 0 || e.type !== 'dir' || entries.length <= 1);
    }
    
    async _ensureDir(remotePath) {
        // Try MKCOL — ignore 405 (already exists) and 409 (parent missing)
        const response = await this._webdavRequest('MKCOL', remotePath);
        if (response.ok || response.status === 405 || response.status === 301 || response.status === 302) return true;
        if (response.status === 409) {
            // Parent missing — try creating parent recursively
            const parts = remotePath.replace(/\/$/, '').split('/').filter(Boolean);
            if (parts.length > 1) {
                const parent = parts.slice(0, -1).join('/');
                await this._ensureDir(parent);
                // Retry MKCOL
                const retry = await this._webdavRequest('MKCOL', remotePath);
                if (retry.ok || retry.status === 405) return true;
            }
            // Try creating path component by component as a fallback
            let current = '';
            for (const part of parts) {
                current += '/' + part;
                try {
                    const attempt = await this._webdavRequest('MKCOL', current);
                    if (!attempt.ok && attempt.status !== 405) {
                        // Ignore — it likely exists already or we can't create it
                    }
                } catch (e) { /* ignore */ }
            }
            return true;
        }
        return false;
    }
    
    registerCommands() {
        const self = this;
        
        // --- webdav-config: set WebDAV endpoint and credentials ---
        this.commands['webdav-config'] = async (args) => {
            // No args: auto-detect space name and try to configure from token
            if (!args || args.length === 0) {
                const spaceName = self._spaceName;
                if (!spaceName) {
                    self.terminal.print('Could not detect space name from URL.', 'warning');
                    self.terminal.print('Usage: webdav-config <url> [username] [password]', 'info');
                    return;
                }

                // Auto-configure URL from space name
                const autoUrl = 'https://webx11.duckdns.org/spaces/' + spaceName + '/';
                let token = null;

                // Check SecretVault first
                if (window.webx11_secretVault) {
                    token = window.webx11_secretVault.decrypt('webdav_token_' + spaceName);
                }

                // Fallback to localStorage
                if (!token) {
                    token = localStorage.getItem('webx11_spaces_' + spaceName);
                }

                if (token) {
                    self.config = {
                        url: autoUrl,
                        username: spaceName,
                        password: token
                    };
                    self._saveConfig();
                    self._autoConfigured = true;
                    self.terminal.print('Auto-configured WebDAV for space: ' + spaceName, 'success');
                    try {
                        const resp = await self._webdavRequest('OPTIONS', '/');
                        self.terminal.print('Connected: ' + resp.status + ' ' + resp.statusText, 'success');
                        self.terminal.print('WebDAV configured: ' + self.config.url, 'success');
                    } catch (e) {
                        self.terminal.print('Connection test failed: ' + e.message, 'warning');
                        self.terminal.print('Config saved but connection may need CORS or network access.', 'warning');
                    }
                } else {
                    self.terminal.print('No WebDAV token found for space: ' + spaceName, 'warning');
                    self.terminal.print('Get your token from /spaces/' + spaceName + '/.token or the dashboard.', 'info');
                    self.terminal.print('Auto-setting URL: ' + autoUrl, 'info');
                    self.terminal.print('Then configure with: webdav-config ' + autoUrl + ' ' + spaceName + ' <your-token>', 'info');
                    // At minimum set the URL
                    self.config = {
                        url: autoUrl,
                        username: spaceName,
                        password: ''
                    };
                    self._saveConfig();
                    self._autoConfigured = true;
                }
                return;
            }

            // Legacy 1-3 arg behavior
            self.config = {
                url: args[0],
                username: args[1] || (self.config ? self.config.username : ''),
                password: args[2] || (self.config ? self.config.password : '')
            };
            self._saveConfig();
            self.terminal.print('Testing WebDAV connection...', 'info');
            try {
                const resp = await self._webdavRequest('OPTIONS', '/');
                self.terminal.print('Connected: ' + resp.status + ' ' + resp.statusText, 'success');
                self.terminal.print('WebDAV configured: ' + self.config.url, 'success');
            } catch (e) {
                self.terminal.print('Connection test failed: ' + e.message, 'warning');
                self.terminal.print('Config saved but connection may need CORS or network access.', 'warning');
            }
        };
        
        // --- webdav-status: show current WebDAV config ---
        this.commands['webdav-status'] = () => {
            if (!self.config || !self.config.url) {
                self.terminal.print('WebDAV not configured. Use webdav-config <url> [username] [password]', 'warning');
                return;
            }
            self.terminal.print('WebDAV Status:', 'text-muted');
            self.terminal.print('  URL: ' + self.config.url);
            self.terminal.print('  User: ' + (self.config.username || '(none)'));
            self.terminal.print('  Password: ' + (self.config.password ? '**** (' + self.config.password.length + ' chars)' : '(none)'));
            self.terminal.print('  Space detected: ' + (self._spaceName || '(none)'));
            if (self._autoConfigured) {
                self.terminal.print('  Auto-configured: yes', 'success');
            }
        };
        
        // --- webdav-ls: list remote directory ---
        this.commands['webdav-ls'] = async (args) => {
            const remotePath = args[0] || '/';
            try {
                const entries = await self._listDir(remotePath);
                if (entries.length === 0) {
                    self.terminal.print('(empty)', 'info');
                    return;
                }
                entries.forEach(e => {
                    const icon = e.type === 'dir' ? '📁' : '📄';
                    const sizeStr = e.type === 'file' ? ' (' + self._formatSize(e.size) + ')' : '/';
                    self.terminal.print(icon + ' ' + e.name + (e.type === 'dir' ? '/' : '') + (e.type === 'file' ? sizeStr : ''));
                });
                self.terminal.print(entries.length + ' item(s)', 'text-muted');
            } catch (e) {
                self.terminal.print('Failed to list: ' + e.message, 'error');
            }
        };
        
        // --- webdav-push: upload a VFS file to WebDAV ---
        this.commands['webdav-push'] = async (args) => {
            if (!args[0]) {
                self.terminal.print('Usage: webdav-push <vfs-path> [remote-path]', 'warning');
                return;
            }
            const vfsPath = args[0];
            const remotePath = args[1] || vfsPath;
            const content = self.terminal.fs.readFile(vfsPath);
            if (content === null) {
                self.terminal.print('File not found in VFS: ' + vfsPath, 'error');
                return;
            }
            try {
                // Ensure remote dir exists
                const parts = remotePath.replace(/\/$/, '').split('/').filter(Boolean);
                if (parts.length > 1) {
                    const parent = parts.slice(0, -1).join('/');
                    await self._ensureDir(parent);
                }
                const resp = await self._webdavRequest('PUT', remotePath, {
                    body: content,
                    headers: { 'Content-Type': 'text/plain' }
                });
                if (resp.ok || resp.status === 201 || resp.status === 204) {
                    self.terminal.print('Pushed: ' + vfsPath + ' → ' + remotePath, 'success');
                } else {
                    self.terminal.print('Push failed: HTTP ' + resp.status, 'error');
                }
            } catch (e) {
                self.terminal.print('Push error: ' + e.message, 'error');
            }
        };
        
        // --- webdav-pull: download a WebDAV file to VFS ---
        this.commands['webdav-pull'] = async (args) => {
            if (!args[0]) {
                self.terminal.print('Usage: webdav-pull <remote-path> [vfs-path]', 'warning');
                return;
            }
            const remotePath = args[0];
            const vfsPath = args[1] || remotePath.split('/').pop();
            try {
                const resp = await self._webdavRequest('GET', remotePath);
                if (!resp.ok) throw new Error('HTTP ' + resp.status);
                const content = await resp.text();
                self.terminal.fs.writeFile(vfsPath, content);
                self.terminal.print('Pulled: ' + remotePath + ' → ' + vfsPath + ' (' + content.length + ' bytes)', 'success');
            } catch (e) {
                self.terminal.print('Pull error: ' + e.message, 'error');
            }
        };
        
        // --- webdav-backup: backup entire VFS to WebDAV ---
        this.commands['webdav-backup'] = async (args) => {
            const name = (args[0] || 'backup').replace(/[^a-zA-Z0-9_-]/g, '_');
            const now = new Date();
            const dateStr = now.getFullYear() + '-' +
                String(now.getMonth() + 1).padStart(2, '0') + '-' +
                String(now.getDate()).padStart(2, '0') + '_' +
                String(now.getHours()).padStart(2, '0') +
                String(now.getMinutes()).padStart(2, '0') +
                String(now.getSeconds()).padStart(2, '0');
            const filename = name + '-' + dateStr + '.json';
            const remotePath = 'backups/' + filename;
            
            try {
                await self._ensureDir('backups');
                const serialized = JSON.stringify(self.terminal.fs.root, null, 2);
                const resp = await self._webdavRequest('PUT', remotePath, {
                    body: serialized,
                    headers: { 'Content-Type': 'application/json' }
                });
                if (resp.ok || resp.status === 201 || resp.status === 204) {
                    self.terminal.print('Backup saved: ' + remotePath + ' (' + self._formatSize(serialized.length) + ')', 'success');
                } else {
                    self.terminal.print('Backup failed: HTTP ' + resp.status, 'error');
                }
            } catch (e) {
                self.terminal.print('Backup error: ' + e.message, 'error');
            }
        };
        
        // --- webdav-restore: restore VFS from a WebDAV backup ---
        this.commands['webdav-restore'] = async (args) => {
            if (!args[0]) {
                self.terminal.print('Usage: webdav-restore <backup-filename>', 'warning');
                self.terminal.print('  Use webdav-ls backups/ to see available backups', 'info');
                return;
            }
            let remotePath = args[0];
            if (!remotePath.startsWith('backups/') && !remotePath.startsWith('/backups/')) {
                remotePath = 'backups/' + remotePath;
            }
            try {
                const resp = await self._webdavRequest('GET', remotePath);
                if (!resp.ok) throw new Error('HTTP ' + resp.status);
                const content = await resp.text();
                const data = JSON.parse(content);
                if (!data || !data.type) {
                    self.terminal.print('Invalid backup file (not a valid VFS export)', 'error');
                    return;
                }
                if (self.terminal.fs.restoreFromExport(data)) {
                    self.terminal.updatePrompt();
                    self.terminal.print('VFS restored from: ' + remotePath, 'success');
                    self.terminal.executeCommand('ls');
                } else {
                    self.terminal.print('Failed to restore VFS from backup', 'error');
                }
            } catch (e) {
                self.terminal.print('Restore error: ' + e.message, 'error');
            }
        };
        
        // --- webdav-backup-list: list available backups ---
        this.commands['webdav-backup-list'] = async () => {
            try {
                const entries = await self._listDir('backups');
                if (entries.length === 0) {
                    self.terminal.print('No backups found', 'info');
                    return;
                }
                self.terminal.print('Available backups:', 'text-muted');
                entries.forEach(e => {
                    if (e.type === 'file') {
                        self.terminal.print('  ' + e.name + '  (' + self._formatSize(e.size) + ')');
                    }
                });
            } catch (e) {
                self.terminal.print('Failed to list backups: ' + e.message, 'info');
                self.terminal.print('  (backups directory may not exist yet — run webdav-backup first)', 'info');
            }
        };

        // --- webdav-explorer: interactive file browser via WebDAV ---
        this.commands['webdav-explorer'] = async (args) => {
            const startPath = args[0] || '/';
            try {
                const entries = await self._listDir(startPath);
                self.terminal.print('📁 WebDAV: ' + startPath, 'info');
                if (entries.length === 0) {
                    self.terminal.print('(empty)', 'info');
                    return;
                }
                entries.forEach(e => {
                    const icon = e.type === 'dir' ? '📁' : '📄';
                    const size = e.type === 'file' ? ' (' + self._formatSize(e.size) + ')' : '/';
                    self.terminal.print(icon + ' ' + e.name + (e.type === 'dir' ? '/' : '') + size);
                });
                self.terminal.print('---');
                self.terminal.print('↳ Navigate: webdav-explorer <dir> | Pull: webdav-pull <file>', 'text-muted');
                self.terminal.print(entries.length + ' item(s)', 'text-muted');
            } catch (e) {
                self.terminal.print('WebDAV error: ' + e.message, 'error');
            }
        };
    }

    _formatSize(bytes) {
        if (bytes < 1024) return bytes + ' B';
        if (bytes < 1024 * 1024) return (bytes / 1024).toFixed(1) + ' KB';
        return (bytes / (1024 * 1024)).toFixed(1) + ' MB';
    }
}