<?php
/**
 * Analytics API
 * 
 * GET /api/analytics.php?action=overview&days=30
 * GET /api/analytics.php?action=timeseries&metric=views&days=30
 * GET /api/analytics.php?action=top_videos&metric=views&limit=10
 * GET /api/analytics.php?action=demographics&days=30
 * GET /api/analytics.php?action=traffic_sources&days=30
 * GET /api/analytics.php?action=retention&video_id=X&days=30
 * POST /api/analytics.php?action=track - Track event
 */

require_once dirname(__DIR__) . '/f_core/config.boot.php';
require_once dirname(__DIR__) . '/f_core/f_classes/class.analytics.php';

header('Content-Type: application/json');

session_start();
$current_user_id = $_SESSION['user_id'] ?? null;
$analytics = new VAnalytics();

$action = $_GET['action'] ?? 'overview';
$days = intval($_GET['days'] ?? 30);

// Track event (public endpoint)
if ($action === 'track') {
    if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
        http_response_code(405);
        echo json_encode(['success' => false, 'error' => 'Method not allowed']);
        exit;
    }
    
    $input = json_decode(file_get_contents('php://input'), true) ?: $_POST;
    
    $video_id = $input['video_id'] ?? null;
    $event_type = $input['event_type'] ?? 'view';
    
    if (!$video_id) {
        http_response_code(400);
        echo json_encode(['success' => false, 'error' => 'Video ID required']);
        exit;
    }
    
    $data = [
        'usr_id' => $current_user_id,
        'watch_duration' => $input['watch_duration'] ?? 0,
        'completion_percentage' => $input['completion_percentage'] ?? 0,
        'country_code' => $input['country_code'] ?? null
    ];
    
    $result = $analytics->trackEvent($video_id, $event_type, $data);
    
    // Track retention if provided
    if (isset($input['minute'])) {
        $analytics->trackRetention($video_id, $input['minute']);
    }
    
    // Track traffic source if provided
    if (isset($input['source_type'])) {
        // Get video owner
        global $class_database;
        $sql = "SELECT usr_id FROM db_videofiles WHERE video_id = ?";
        $res = $class_database->execute($sql, [$video_id]);
        if ($res && $row = $class_database->fetch($res)) {
            $analytics->trackTrafficSource(
                $video_id,
                $row['usr_id'],
                $input['source_type'],
                $input['source_detail'] ?? ''
            );
        }
    }
    
    echo json_encode(['success' => (bool)$result]);
    exit;
}

// All other actions require authentication
if (!$current_user_id) {
    http_response_code(401);
    echo json_encode(['success' => false, 'error' => 'Authentication required']);
    exit;
}

// Handle analytics queries
switch ($action) {
    case 'overview':
        $data = $analytics->getChannelOverview($current_user_id, $days);
        echo json_encode(['success' => true, 'data' => $data]);
        break;
        
    case 'timeseries':
        $metric = $_GET['metric'] ?? 'views';
        $data = $analytics->getChannelTimeSeries($current_user_id, $days, $metric);
        echo json_encode(['success' => true, 'data' => $data]);
        break;
        
    case 'top_videos':
        $metric = $_GET['metric'] ?? 'views';
        $limit = intval($_GET['limit'] ?? 10);
        $data = $analytics->getTopVideos($current_user_id, $days, $metric, $limit);
        echo json_encode(['success' => true, 'data' => $data]);
        break;
        
    case 'demographics':
        $data = $analytics->getDemographics($current_user_id, $days);
        echo json_encode(['success' => true, 'data' => $data]);
        break;
        
    case 'traffic_sources':
        $data = $analytics->getTrafficSources($current_user_id, $days);
        echo json_encode(['success' => true, 'data' => $data]);
        break;
        
    case 'retention':
        $video_id = $_GET['video_id'] ?? null;
        
        if (!$video_id) {
            http_response_code(400);
            echo json_encode(['success' => false, 'error' => 'Video ID required']);
            exit;
        }
        
        // Verify ownership
        global $class_database;
        $sql = "SELECT usr_id FROM db_videofiles WHERE video_id = ?";
        $result = $class_database->execute($sql, [$video_id]);
        
        if (!$result || $class_database->rowCount($result) == 0) {
            http_response_code(404);
            echo json_encode(['success' => false, 'error' => 'Video not found']);
            exit;
        }
        
        $row = $class_database->fetch($result);
        
        if ($row['usr_id'] != $current_user_id) {
            http_response_code(403);
            echo json_encode(['success' => false, 'error' => 'Permission denied']);
            exit;
        }
        
        $data = $analytics->getAudienceRetention($video_id, $days);
        echo json_encode(['success' => true, 'data' => $data]);
        break;
        
    default:
        http_response_code(400);
        echo json_encode(['success' => false, 'error' => 'Invalid action']);
}