/**
 * HF Uploader Dashboard - JavaScript Application
 */

// ============================================================================
// API Client
// ============================================================================

class APIClient {
    constructor(baseURL = '/api') {
        this.baseURL = baseURL;
    }

    async request(endpoint, options = {}) {
        const url = `${this.baseURL}${endpoint}`;
        const response = await fetch(url, {
            headers: {
                'Content-Type': 'application/json',
                ...options.headers,
            },
            ...options,
        });

        if (!response.ok) {
            const error = await response.json().catch(() => ({ detail: response.statusText }));
            throw new Error(error.detail || `HTTP ${response.status}`);
        }

        return response.json();
    }

    // Configuration endpoints
    getConfig() {
        return this.request('/config');
    }

    updateConfig(data) {
        return this.request('/config', {
            method: 'POST',
            body: JSON.stringify(data),
        });
    }

    // Queue endpoints
    getQueue(status = null) {
        const url = status ? `/queue?status=${status}` : '/queue';
        return this.request(url);
    }

    getQueueStats() {
        return this.request('/queue/stats');
    }

    addToQueue() {
        return this.request('/queue/add', { method: 'POST' });
    }

    clearQueue() {
        return this.request('/queue/clear', { method: 'POST' });
    }

    // Processing endpoints
    getProcessingState() {
        return this.request('/processing/state');
    }

    startProcessing(maxFiles = 0) {
        return this.request('/processing/start', {
            method: 'POST',
            body: JSON.stringify({ max_files: maxFiles }),
        });
    }

    getProcessedFiles() {
        return this.request('/processing/files');
    }

    // Upload endpoints
    startUpload(fileIds, batchSize = 10) {
        return this.request('/upload/start', {
            method: 'POST',
            body: JSON.stringify({ file_ids: fileIds, batch_size: batchSize }),
        });
    }

    getUploadStatus() {
        return this.request('/upload/status');
    }

    retryUpload(itemId) {
        return this.request(`/upload/retry/${itemId}`, { method: 'POST' });
    }

    // File endpoints
    previewFile(filename) {
        return this.request('/file/preview', {
            method: 'POST',
            body: JSON.stringify({ filename }),
        });
    }

    // Error log endpoints
    getErrorLogs(limit = 50) {
        return this.request(`/errors?limit=${limit}`);
    }

    clearErrorLogs() {
        return this.request('/errors', { method: 'DELETE' });
    }
}

// ============================================================================
// Notification System
// ============================================================================

class Notifier {
    constructor() {
        this.toastEl = document.getElementById('toast');
        this.timeout = null;
    }

    show(message, type = 'info', duration = 3000) {
        this.toastEl.textContent = message;
        this.toastEl.className = `toast show ${type}`;

        clearTimeout(this.timeout);
        this.timeout = setTimeout(() => {
            this.toastEl.classList.remove('show');
        }, duration);
    }

    success(message) {
        this.show(message, 'success');
    }

    error(message) {
        this.show(message, 'error', 5000);
    }

    warning(message) {
        this.show(message, 'warning', 4000);
    }

    info(message) {
        this.show(message, 'info');
    }
}

// ============================================================================
// Dashboard Application
// ============================================================================

class Dashboard {
    constructor() {
        this.api = new APIClient();
        this.notifier = new Notifier();
        this.currentSection = 'dashboard';
        this.refreshInterval = null;

        this.init();
    }

    init() {
        this.setupEventListeners();
        this.loadInitialData();
        this.startAutoRefresh();
    }

    setupEventListeners() {
        // Navigation
        document.querySelectorAll('.nav-link').forEach(link => {
            link.addEventListener('click', (e) => {
                e.preventDefault();
                const section = link.dataset.section;
                this.switchSection(section);
            });
        });

        // Dashboard buttons
        document.getElementById('btn-start-processing').addEventListener('click', () => this.startProcessing());
        document.getElementById('btn-start-upload').addEventListener('click', () => this.startUpload());

        // Queue buttons
        document.getElementById('btn-add-to-queue').addEventListener('click', () => this.addToQueue());
        document.getElementById('btn-clear-queue').addEventListener('click', () => this.clearQueue());
        document.getElementById('queue-filter').addEventListener('change', (e) => this.filterQueue(e.target.value));

        // Configuration buttons
        document.getElementById('btn-save-config').addEventListener('click', () => this.saveConfig());

        // Logs buttons
        document.getElementById('btn-clear-logs').addEventListener('click', () => this.clearLogs());

        // Modal close
        document.querySelector('.modal-close').addEventListener('click', () => this.closeModal());
    }

    switchSection(section) {
        // Hide all sections
        document.querySelectorAll('.section').forEach(s => s.classList.remove('active'));
        // Show selected section
        document.getElementById(section).classList.add('active');

        // Update nav
        document.querySelectorAll('.nav-link').forEach(link => {
            link.classList.toggle('active', link.dataset.section === section);
        });

        this.currentSection = section;

        // Load section-specific data
        if (section === 'queue') {
            this.loadQueue();
        } else if (section === 'logs') {
            this.loadErrorLogs();
        }
    }

    async loadInitialData() {
        try {
            await this.loadConfig();
            await this.loadStats();
            await this.loadProcessingState();
            await this.loadUploadStatus();
        } catch (error) {
            this.notifier.error(`Failed to load data: ${error.message}`);
        }
    }

    async loadConfig() {
        try {
            const config = await this.api.getConfig();
            document.getElementById('hf-token').value = config.hf_token || '';
            document.getElementById('source-all-repo').value = config.source_all_repo;
            document.getElementById('source-ato-repo').value = config.source_ato_repo;
            document.getElementById('target-repo').value = config.target_repo;
            document.getElementById('batch-size').value = config.upload_batch_size;
            document.getElementById('max-uploads').value = config.max_uploads_per_hour;
        } catch (error) {
            console.error('Failed to load config:', error);
        }
    }

    async loadStats() {
        try {
            const stats = await this.api.getQueueStats();
            document.getElementById('stat-pending').textContent = stats.pending;
            document.getElementById('stat-uploaded').textContent = stats.completed;
            document.getElementById('stat-failed').textContent = stats.failed;

            const processed = await this.api.getProcessedFiles();
            document.getElementById('stat-processed').textContent = processed.count;
        } catch (error) {
            console.error('Failed to load stats:', error);
        }
    }

    async loadProcessingState() {
        try {
            const state = await this.api.getProcessingState();
            document.getElementById('processing-status').textContent = state.status;
            document.getElementById('matched-pairs').textContent = state.matched_pairs;

            if (state.total_files > 0) {
                const progress = (state.processed_files / state.total_files) * 100;
                document.getElementById('processing-progress').style.width = `${progress}%`;
            }
        } catch (error) {
            console.error('Failed to load processing state:', error);
        }
    }

    async loadUploadStatus() {
        try {
            const status = await this.api.getUploadStatus();
            const rateLimitEl = document.getElementById('rate-limit-status');
            const remainingEl = document.getElementById('remaining-uploads');

            if (status.rate_limit.can_upload) {
                rateLimitEl.textContent = 'Ready';
                rateLimitEl.style.color = 'var(--color-success)';
            } else {
                rateLimitEl.textContent = 'Limited';
                rateLimitEl.style.color = 'var(--color-error)';
            }

            remainingEl.textContent = status.rate_limit.remaining_uploads;
        } catch (error) {
            console.error('Failed to load upload status:', error);
        }
    }

    async loadQueue(status = null) {
        try {
            const items = await this.api.getQueue(status);
            const tbody = document.getElementById('queue-tbody');

            if (items.length === 0) {
                tbody.innerHTML = '<tr class="empty-row"><td colspan="5">No files in queue</td></tr>';
                return;
            }

            tbody.innerHTML = items.map(item => `
                <tr>
                    <td>${this.escapeHtml(item.file_name)}</td>
                    <td>${this.formatBytes(item.file_size)}</td>
                    <td><span class="status-badge status-${item.status}">${item.status}</span></td>
                    <td>${item.retry_count}/${item.max_retries}</td>
                    <td>
                        ${item.status === 'failed' ? `<button class="btn btn-secondary" onclick="dashboard.retryFile(${item.id})">Retry</button>` : ''}
                        <button class="btn btn-secondary" onclick="dashboard.previewFile('${this.escapeHtml(item.file_name)}')">Preview</button>
                    </td>
                </tr>
            `).join('');
        } catch (error) {
            this.notifier.error(`Failed to load queue: ${error.message}`);
        }
    }

    async filterQueue(status) {
        await this.loadQueue(status || null);
    }

    async loadErrorLogs() {
        try {
            const logs = await this.api.getErrorLogs();
            const tbody = document.getElementById('logs-tbody');

            if (logs.length === 0) {
                tbody.innerHTML = '<tr class="empty-row"><td colspan="5">No errors logged</td></tr>';
                return;
            }

            tbody.innerHTML = logs.map(log => `
                <tr>
                    <td>${this.escapeHtml(log.file_name)}</td>
                    <td>${log.error_code || 'N/A'}</td>
                    <td>${this.escapeHtml(log.error_message || '')}</td>
                    <td>${log.retryable ? 'Yes' : 'No'}</td>
                    <td>${new Date(log.created_at).toLocaleString()}</td>
                </tr>
            `).join('');
        } catch (error) {
            this.notifier.error(`Failed to load error logs: ${error.message}`);
        }
    }

    async startProcessing() {
        try {
            const btn = document.getElementById('btn-start-processing');
            btn.disabled = true;
            this.notifier.info('Starting dataset processing...');

            await this.api.startProcessing(0);
            this.notifier.success('Processing started');

            // Refresh state periodically
            this.refreshInterval = setInterval(() => this.loadProcessingState(), 2000);
        } catch (error) {
            this.notifier.error(`Failed to start processing: ${error.message}`);
            document.getElementById('btn-start-processing').disabled = false;
        }
    }

    async startUpload() {
        try {
            const stats = await this.api.getQueueStats();
            if (stats.pending === 0) {
                this.notifier.warning('No pending files to upload');
                return;
            }

            const btn = document.getElementById('btn-start-upload');
            btn.disabled = true;
            this.notifier.info('Starting upload...');

            // Get all pending files
            const queue = await this.api.getQueue('pending');
            const fileIds = queue.map(item => item.id);

            await this.api.startUpload(fileIds);
            this.notifier.success('Upload started');

            // Refresh stats periodically
            this.refreshInterval = setInterval(() => this.loadStats(), 2000);
        } catch (error) {
            this.notifier.error(`Failed to start upload: ${error.message}`);
            document.getElementById('btn-start-upload').disabled = false;
        }
    }

    async addToQueue() {
        try {
            const btn = document.getElementById('btn-add-to-queue');
            btn.disabled = true;

            const result = await this.api.addToQueue();
            this.notifier.success(`Added ${result.added} files to queue`);

            await this.loadQueue();
            await this.loadStats();

            btn.disabled = false;
        } catch (error) {
            this.notifier.error(`Failed to add to queue: ${error.message}`);
            document.getElementById('btn-add-to-queue').disabled = false;
        }
    }

    async clearQueue() {
        if (!confirm('Are you sure you want to clear the entire queue?')) {
            return;
        }

        try {
            await this.api.clearQueue();
            this.notifier.success('Queue cleared');
            await this.loadQueue();
            await this.loadStats();
        } catch (error) {
            this.notifier.error(`Failed to clear queue: ${error.message}`);
        }
    }

    async saveConfig() {
        try {
            const config = {
                hf_token: document.getElementById('hf-token').value,
                source_all_repo: document.getElementById('source-all-repo').value,
                source_ato_repo: document.getElementById('source-ato-repo').value,
                target_repo: document.getElementById('target-repo').value,
                upload_batch_size: parseInt(document.getElementById('batch-size').value),
                max_uploads_per_hour: parseInt(document.getElementById('max-uploads').value),
            };

            const btn = document.getElementById('btn-save-config');
            btn.disabled = true;

            await this.api.updateConfig(config);
            this.notifier.success('Configuration saved');

            btn.disabled = false;
        } catch (error) {
            this.notifier.error(`Failed to save configuration: ${error.message}`);
            document.getElementById('btn-save-config').disabled = false;
        }
    }

    async retryFile(itemId) {
        try {
            await this.api.retryUpload(itemId);
            this.notifier.success('Retry scheduled');
            await this.loadQueue();
        } catch (error) {
            this.notifier.error(`Failed to retry: ${error.message}`);
        }
    }

    async previewFile(filename) {
        try {
            const data = await this.api.previewFile(filename);
            const modal = document.getElementById('preview-modal');
            const content = document.getElementById('preview-content');

            content.textContent = JSON.stringify(data.content, null, 2);
            modal.classList.add('show');
        } catch (error) {
            this.notifier.error(`Failed to preview file: ${error.message}`);
        }
    }

    closeModal() {
        document.getElementById('preview-modal').classList.remove('show');
    }

    async clearLogs() {
        if (!confirm('Are you sure you want to clear all error logs?')) {
            return;
        }

        try {
            await this.api.clearErrorLogs();
            this.notifier.success('Error logs cleared');
            await this.loadErrorLogs();
        } catch (error) {
            this.notifier.error(`Failed to clear logs: ${error.message}`);
        }
    }

    startAutoRefresh() {
        setInterval(() => {
            if (this.currentSection === 'dashboard') {
                this.loadStats();
                this.loadProcessingState();
                this.loadUploadStatus();
            }
        }, 5000);
    }

    escapeHtml(text) {
        const div = document.createElement('div');
        div.textContent = text;
        return div.innerHTML;
    }

    formatBytes(bytes) {
        if (bytes === 0) return '0 B';
        const k = 1024;
        const sizes = ['B', 'KB', 'MB', 'GB'];
        const i = Math.floor(Math.log(bytes) / Math.log(k));
        return Math.round((bytes / Math.pow(k, i)) * 100) / 100 + ' ' + sizes[i];
    }
}

// ============================================================================
// Initialize Dashboard
// ============================================================================

let dashboard;
document.addEventListener('DOMContentLoaded', () => {
    dashboard = new Dashboard();
});