-- Create users table
CREATE TABLE IF NOT EXISTS `users` (
  `id` INT AUTO_INCREMENT PRIMARY KEY,
  `email` VARCHAR(255) NOT NULL UNIQUE,
  `password` VARCHAR(255) NOT NULL,
  `role` ENUM('student', 'teacher', 'admin') NOT NULL,
  `full_name` VARCHAR(255) DEFAULT NULL,
  `created_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
  `updated_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- Create leave_requests table
CREATE TABLE IF NOT EXISTS `leave_requests` (
  `id` INT AUTO_INCREMENT PRIMARY KEY,
  `student_id` INT NOT NULL,
  `start_date` DATE NOT NULL,
  `end_date` DATE NOT NULL,
  `reason` TEXT,
  `status` ENUM('pending_teacher', 'pending_admin', 'approved', 'rejected') NOT NULL DEFAULT 'pending_teacher',
  `teacher_id` INT DEFAULT NULL,
  `teacher_approved_at` DATETIME DEFAULT NULL,
  `teacher_rejection_reason` TEXT DEFAULT NULL,
  `admin_id` INT DEFAULT NULL,
  `admin_approved_at` DATETIME DEFAULT NULL,
  `admin_rejection_reason` TEXT DEFAULT NULL,
  `created_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
  `updated_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP,
  FOREIGN KEY (`student_id`) REFERENCES `users`(`id`) ON DELETE CASCADE,
  FOREIGN KEY (`teacher_id`) REFERENCES `users`(`id`) ON DELETE SET NULL,
  FOREIGN KEY (`admin_id`) REFERENCES `users`(`id`) ON DELETE SET NULL
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- Create leave_request_attachments table
CREATE TABLE IF NOT EXISTS `leave_request_attachments` (
  `id` INT AUTO_INCREMENT PRIMARY KEY,
  `leave_request_id` INT NOT NULL,
  `file_path` VARCHAR(255) NOT NULL,
  `original_filename` VARCHAR(255) DEFAULT NULL,
  `created_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
  FOREIGN KEY (`leave_request_id`) REFERENCES `leave_requests`(`id`) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

-- Create password_resets table
CREATE TABLE IF NOT EXISTS `password_resets` (
  `id` INT AUTO_INCREMENT PRIMARY KEY,
  `email` VARCHAR(255) NOT NULL,
  `token` VARCHAR(255) NOT NULL,
  `created_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;