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

require_once __DIR__ . '/../config.php';

if (!defined('OPENAI_API_KEY')) {
    http_response_code(500);
    echo json_encode(['error' => 'API key not configured.']);
    exit;
}

if ($_SERVER['REQUEST_METHOD'] !== 'POST' || !isset($_FILES['vehicleImage'])) {
    http_response_code(400);
    echo json_encode(['error' => 'Invalid request.']);
    exit;
}

$file = $_FILES['vehicleImage'];

if ($file['error'] !== UPLOAD_ERR_OK) {
    http_response_code(500);
    echo json_encode(['error' => 'Error uploading file.']);
    exit;
}

// Check file type
$mime_type = mime_content_type($file['tmp_name']);
if (strpos($mime_type, 'image') !== 0) {
    http_response_code(400);
    echo json_encode(['error' => 'Invalid file type. Please upload an image.']);
    exit;
}

$imageData = file_get_contents($file['tmp_name']);
$base64Image = base64_encode($imageData);

$payload = [
    'model' => 'gpt-4o',
    'messages' => [
        [
            'role' => 'system',
            'content' => 'You are an expert in vehicle damage assessment. Analyze the provided image to identify the vehicle\'s make, model, and color, and find all damages. Respond with a single JSON object with two top-level keys: "carInfo" and "defects". The "carInfo" key should contain an object with "make", "model", and "color". The "defects" key should contain an array of objects, where each object has two keys: "defect" (a string describing the damage) and "cost" (a number representing the estimated repair cost in EUR).'
        ],
        [
            'role' => 'user',
            'content' => [
                [
                    'type' => 'text',
                    'text' => 'Please analyze the attached image for vehicle defects and list them.'
                ],
                [
                    'type' => 'image_url',
                    'image_url' => [
                        'url' => "data:{$mime_type};base64,{$base64Image}"
                    ]
                ]
            ]
        ]
    ],
    'response_format' => ['type' => 'json_object'],
    'max_tokens' => 1000
];

$ch = curl_init('https://api.openai.com/v1/chat/completions');
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, json_encode($payload));
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'Content-Type: application/json',
    'Authorization: Bearer ' . OPENAI_API_KEY
]);

$response = curl_exec($ch);
$httpcode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
curl_close($ch);

if ($httpcode >= 400) {
    http_response_code($httpcode);
    // Forward the error from OpenAI if possible
    $error_response = json_decode($response, true);
    if (isset($error_response['error']['message'])) {
        echo json_encode(['error' => 'OpenAI API Error: ' . $error_response['error']['message']]);
    } else {
        echo json_encode(['error' => 'An error occurred with the OpenAI API.']);
    }
    exit;
}

$result = json_decode($response, true);

if (isset($result['choices'][0]['message']['content'])) {
    // The response from OpenAI is a JSON string, so we need to decode it again
    $defects_json = $result['choices'][0]['message']['content'];
    $defects_data = json_decode($defects_json, true);
    
    if (json_last_error() === JSON_ERROR_NONE && (isset($defects_data['defects']) || isset($defects_data['carInfo']))) {
        echo json_encode($defects_data);
    } else {
        // Handle cases where the response is not the expected JSON
        http_response_code(500);
        echo json_encode(['error' => 'Failed to parse defects from API response.', 'raw_response' => $defects_json]);
    }
} else {
    http_response_code(500);
    echo json_encode(['error' => 'No content received from API.', 'raw_response' => $response]);
}
?>