<?php
// backend/check_status.php

require_once __DIR__ . '/config.php';

/**
 * Handles error responses for the API.
 * @param string $message The error message.
 * @param int $statusCode The HTTP status code (default 500).
 */
function sendErrorResponse($message, $statusCode = 500) {
    http_response_code($statusCode);
    echo json_encode(['status' => 'error', 'message' => $message]);
    exit();
}

/**
 * Get nested value from array using dot notation
 * @param array $array The array to search
 * @param string $path Dot-separated path like 'output.0.url'
 * @return mixed|null The value or null if not found
 */
function getNestedValue($array, $path) {
    $keys = explode('.', $path);
    $current = $array;
    
    foreach ($keys as $key) {
        if (is_array($current) && isset($current[$key])) {
            $current = $current[$key];
        } else {
            return null;
        }
    }
    
    return $current;
}

// Ensure the request method is GET
if ($_SERVER['REQUEST_METHOD'] !== 'GET') {
    sendErrorResponse('Method Not Allowed', 405);
}

$jobId = $_GET['job_id'] ?? null;

if (empty($jobId)) {
    sendErrorResponse('Job ID is required', 400);
}

try {
    // Check if API key is available
    if (!defined('RUNWAY_API_KEY') || empty(RUNWAY_API_KEY)) {
        throw new Exception('Runway API key not configured. Please check your .env file.');
    }
    
    // Validate job ID format (should be a UUID)
    if (!preg_match('/^[0-9a-f]{8}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{4}-[0-9a-f]{12}$/i', $jobId)) {
        throw new Exception('Invalid job ID format');
    }
    
    error_log("Checking status for job ID: " . $jobId);
    
    // Check job status with Runway API
    $runwayStatusEndpoint = "https://api.dev.runwayml.com/v1/tasks/{$jobId}";
    
    $ch = curl_init($runwayStatusEndpoint);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_HTTPGET, true);
    curl_setopt($ch, CURLOPT_HTTPHEADER, [
        'Authorization: Bearer ' . RUNWAY_API_KEY,
        'X-Runway-Version: 2024-11-06'
    ]);
    
    $response = curl_exec($ch);
    $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    $curlError = curl_error($ch);
    curl_close($ch);
    
    if ($response === false) {
        throw new Exception("cURL error checking job status: " . $curlError);
    }
    
    error_log("Status check response HTTP code: " . $httpCode);
    error_log("Status check response body: " . $response);
    
    $result = json_decode($response, true);
    
    if ($httpCode >= 400) {
        $errorMessage = 'Unknown error checking job status';
        if (isset($result['error']['message'])) {
            $errorMessage = $result['error']['message'];
        } elseif (isset($result['message'])) {
            $errorMessage = $result['message'];
        }
        throw new Exception("Error checking job status ($httpCode): " . $errorMessage . ". Response: " . $response);
    }
    
    // Parse the task status response
    $status = $result['status'] ?? 'unknown';
    $videoUrl = null;
    
    // Check if task is completed and has output
    if ($status === 'SUCCEEDED' || $status === 'completed') {
        // Look for video URL in various possible locations based on Runway API docs
        // Handle the actual Runway response format from logs
        if (isset($result['output']) && is_array($result['output']) && !empty($result['output'])) {
            // Runway returns output as array of URLs, take the first one
            $videoUrl = $result['output'][0];
        }
        
        // Fallback to other possible locations if not found
        if (!$videoUrl) {
            $possiblePaths = [
                'output.url', 
                'artifacts.0.url',
                'artifacts.url',
                'video.url',
                'video_url',
                'url',
                'result.url',
                'result.video_url'
            ];
            
            foreach ($possiblePaths as $path) {
                $videoUrl = getNestedValue($result, $path);
                if ($videoUrl) {
                    break;
                }
            }
        }
        
        // Log what we found for debugging
        error_log("Task completed with status: $status");
        error_log("Video URL found: " . ($videoUrl ?: 'NONE'));
        error_log("Full response keys: " . implode(', ', array_keys($result)));
    }
    
    // Return status to frontend
    echo json_encode([
        'job_id' => $jobId,
        'status' => $status,
        'video_url' => $videoUrl,
        'progress' => $result['progress'] ?? null,
        'message' => $result['message'] ?? null,
        'raw_response' => $result // For debugging
    ]);
    
} catch (Exception $e) {
    error_log("Status check error: " . $e->getMessage());
    sendErrorResponse("Failed to check status: " . $e->getMessage(), 500);
}