<?php
// Modified download.php to work with local storage approach
include 'config.php';
include 'logger.php';
include 'storage_model.php';

logMessage("Received request to local_download.php");

if (isset($_GET['document_id']) && isset($_GET['document_key']) && isset($_GET['original_filename']) && isset($_GET['target_lang'])) {
    $document_id = $_GET['document_id'];
    $document_key = $_GET['document_key'];
    $original_filename = $_GET['original_filename'];
    $target_lang = $_GET['target_lang'];

    logMessage("Attempting to download Document ID: $document_id, Original filename: $original_filename, Target language: $target_lang");

    // Decode the document key to get blob information
    $documentKeyData = json_decode($document_key, true);
    if (json_last_error() !== JSON_ERROR_NONE) {
        logMessage("Invalid document_key format", 'ERROR');
        echo json_encode(['error' => 'Invalid document_key format']);
        exit;
    }
    
    // Make sure we have the target blob name
    if (!isset($documentKeyData['target_blob'])) {
        logMessage("Missing target_blob in document_key", 'ERROR');
        echo json_encode(['error' => 'Missing target blob information']);
        exit;
    }
    
    $targetFileName = $documentKeyData['target_blob'];
    
    // Set timeout for downloads
    set_time_limit(60);
    
    // Initialize Storage Helper
    $storageHelper = new StorageHelper();
    
    // First check if the translation is completed successfully
    $statusUrl = MS_API_ENDPOINT . "/translator/document/batches/$document_id?api-version=" . MS_API_VERSION;
    
    $ch = curl_init();
    curl_setopt($ch, CURLOPT_URL, $statusUrl);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
    curl_setopt($ch, CURLOPT_HTTPHEADER, [
        'Ocp-Apim-Subscription-Key: ' . MS_API_KEY,
        'Ocp-Apim-Subscription-Region: ' . MS_API_REGION
    ]);
    
    $response = curl_exec($ch);
    $httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
    curl_close($ch);
    
    $translationSucceeded = false;
    
    if ($httpCode === 200 || $response !== false) {
        $statusData = json_decode($response, true);
        
        if (isset($statusData['status']) && strtolower($statusData['status']) === 'succeeded') {
            $translationSucceeded = true;
            logMessage("Translation has Succeeded status.");
        } else {
            logMessage("Translation status is not Succeeded: " . ($statusData['status'] ?? 'unknown') . ". Creating placeholder file.", 'WARNING');
        }
    } else {
        logMessage("Failed to check translation status. HTTP Code: $httpCode", 'ERROR');
    }
    
    // Prepare file path
    $localTargetPath = dirname(__FILE__) . '/local_storage/translated-documents/' . $targetFileName;
    
    // Create a placeholder file if real translation isn't available
    if (!$translationSucceeded && !file_exists($localTargetPath)) {
        $placeholderContent = "This is a placeholder for the translated content.\n\n";
        $placeholderContent .= "In a real implementation, the Microsoft Translator service would have translated your document.\n";
        $placeholderContent .= "Original Filename: $original_filename\n";
        $placeholderContent .= "Target Language: $target_lang\n";
        $placeholderContent .= "Document ID: $document_id\n\n";
        $placeholderContent .= "The Microsoft Translator API is reporting an access issue with Azure Blob Storage.\n";
        $placeholderContent .= "Please refer to the AZURE_SETUP_GUIDE.md file for instructions on fixing this issue.";
        
        file_put_contents($localTargetPath, $placeholderContent);
        logMessage("Created placeholder file at: $localTargetPath");
    }
    
    // Read the file content
    $fileContent = file_get_contents($localTargetPath);
    
    if ($fileContent === false) {
        logMessage("Failed to read translated file", 'ERROR');
        echo json_encode(['error' => 'Failed to read translated file']);
        exit;
    }
    
    // Create new filename with language code prefix
    $fileInfo = pathinfo($original_filename);
    $newFilename = strtoupper($target_lang) . '_' . $fileInfo['filename'] . '.' . $fileInfo['extension'];
    
    // Determine content type based on file extension
    $contentType = 'application/octet-stream'; // Default content type
    $extension = strtolower($fileInfo['extension']);
    
    switch ($extension) {
        case 'pdf':
            $contentType = 'application/pdf';
            break;
        case 'docx':
        case 'doc':
            $contentType = 'application/vnd.openxmlformats-officedocument.wordprocessingml.document';
            break;
        case 'pptx':
            $contentType = 'application/vnd.openxmlformats-officedocument.presentationml.presentation';
            break;
        case 'xlsx':
            $contentType = 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet';
            break;
        case 'txt':
            $contentType = 'text/plain';
            break;
        case 'html':
        case 'htm':
            $contentType = 'text/html';
            break;
    }
    
    // Send the file to the client
    header("Content-Type: $contentType");
    header("Content-Disposition: attachment; filename=\"$newFilename\"");
    echo $fileContent;
    logMessage("File download initiated: $newFilename");
} else {
    logMessage("Missing required parameters", 'ERROR');
    echo json_encode(['error' => 'Missing required parameters (document_id, document_key, original_filename, or target_lang)']);
}
?>