# Upload a PDF invoice
curl -X POST "https://api.contazen.ro/v1/expenses/exp_abc123/attachments" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -F "file=@invoice_001.pdf" \
  -F "description=Original supplier invoice"

# Upload an image receipt
curl -X POST "https://api.contazen.ro/v1/expenses/exp_abc123/attachments" \
  -H "Authorization: Bearer YOUR_API_KEY" \
  -F "file=@receipt.jpg" \
  -F "description=Receipt photo"

const uploadAttachment = async (expenseId, file, description = '') => {
  const formData = new FormData();
  formData.append('file', file);
  if (description) {
    formData.append('description', description);
  }

  const response = await fetch(`https://api.contazen.ro/v1/expenses/${expenseId}/attachments`, {
    method: 'POST',
    headers: {
      'Authorization': 'Bearer YOUR_API_KEY'
      // Note: Don't set Content-Type header - let browser set it for multipart/form-data
    },
    body: formData
  });

  const data = await response.json();
  
  if (data.success) {
    console.log('File uploaded:', data.attachment.filename);
    console.log('Download URL:', data.attachment.download_url);
    return data.attachment;
  } else {
    throw new Error(data.error.message);
  }
};

// Usage with file input
const handleFileUpload = async (expenseId, fileInputElement) => {
  const file = fileInputElement.files[0];
  if (!file) return;
  
  try {
    const attachment = await uploadAttachment(expenseId, file, 'Uploaded via web form');
    alert('File uploaded successfully!');
  } catch (error) {
    alert('Upload failed: ' + error.message);
  }
};

// Usage with drag-and-drop
const handleDrop = async (expenseId, event) => {
  event.preventDefault();
  const files = event.dataTransfer.files;
  
  for (let i = 0; i < files.length; i++) {
    try {
      const attachment = await uploadAttachment(expenseId, files[i]);
      console.log(`Uploaded: ${attachment.filename}`);
    } catch (error) {
      console.error(`Failed to upload ${files[i].name}:`, error.message);
    }
  }
};

function uploadExpenseAttachment($expenseId, $filePath, $description = '') {
    if (!file_exists($filePath)) {
        throw new Exception("File not found: $filePath");
    }

    $curl = curl_init();
    
    $postFields = [
        'file' => new CURLFile($filePath),
        'description' => $description
    ];

    curl_setopt_array($curl, [
        CURLOPT_URL => "https://api.contazen.ro/v1/expenses/{$expenseId}/attachments",
        CURLOPT_RETURNTRANSFER => true,
        CURLOPT_POST => true,
        CURLOPT_POSTFIELDS => $postFields,
        CURLOPT_HTTPHEADER => [
            'Authorization: Bearer YOUR_API_KEY'
        ]
    ]);

    $response = curl_exec($curl);
    $httpCode = curl_getinfo($curl, CURLINFO_HTTP_CODE);
    $data = json_decode($response, true);
    curl_close($curl);

    if ($httpCode == 201 && $data['success']) {
        echo "Uploaded: {$data['attachment']['filename']} ({$data['attachment']['filesize']} bytes)\n";
        return $data['attachment'];
    } else {
        throw new Exception($data['error']['message']);
    }
}

// Usage examples
try {
    $attachment = uploadExpenseAttachment('exp_abc123', '/path/to/invoice.pdf', 'Original invoice');
    echo "Download URL: {$attachment['download_url']}\n";
} catch (Exception $e) {
    echo "Upload failed: " . $e->getMessage() . "\n";
}

// Bulk upload from directory
function uploadExpenseAttachmentsFromDirectory($expenseId, $directory) {
    $allowedTypes = ['pdf', 'jpg', 'jpeg', 'png', 'doc', 'docx', 'xls', 'xlsx'];
    $uploadedFiles = [];
    
    foreach (glob("$directory/*") as $filePath) {
        $extension = strtolower(pathinfo($filePath, PATHINFO_EXTENSION));
        
        if (in_array($extension, $allowedTypes)) {
            try {
                $filename = basename($filePath);
                $attachment = uploadExpenseAttachment($expenseId, $filePath, "Auto-uploaded: $filename");
                $uploadedFiles[] = $attachment;
            } catch (Exception $e) {
                echo "Failed to upload $filePath: " . $e->getMessage() . "\n";
            }
        }
    }
    
    return $uploadedFiles;
}

{
  "success": true,
  "attachment": {
    "id": "att_def456",
    "filename": "invoice_001.pdf",
    "filesize": 245760,
    "description": "Original supplier invoice",
    "created_at": "2024-01-20 14:30:00",
    "download_url": "https://api.contazen.ro/v1/files/download/att_def456"
  },
  "message": "Attachment uploaded successfully"
}

{
  "success": false,
  "error": {
    "message": "No file was uploaded or upload failed",
    "type": "invalid_request_error",
    "code": "file_missing"
  }
}

{
  "success": false,
  "error": {
    "message": "Invalid file type. Allowed types: pdf, jpg, jpeg, png, doc, docx, xls, xlsx",
    "type": "invalid_request_error",
    "code": "invalid_file_type",
    "allowed_types": ["pdf", "jpg", "jpeg", "png", "doc", "docx", "xls", "xlsx"]
  }
}

{
  "success": false,
  "error": {
    "message": "File size exceeds maximum allowed size",
    "type": "invalid_request_error",
    "code": "file_too_large",
    "max_size": "10MB"
  }
}

{
  "success": false,
  "error": {
    "message": "Expense not found",
    "type": "invalid_request_error",
    "code": "resource_missing",
    "param": "id"
  }
}

{
  "success": false,
  "error": {
    "message": "Failed to save attachment",
    "type": "api_error",
    "code": "upload_failed",
    "details": "Server error occurred while processing the upload"
  }
}