CREATE TABLE IF NOT EXISTS `warehouses` (
    `id` INT AUTO_INCREMENT PRIMARY KEY,
    `name` VARCHAR(255) NOT NULL,
    `created_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

CREATE TABLE IF NOT EXISTS `slots` (
    `id` INT AUTO_INCREMENT PRIMARY KEY,
    `name` VARCHAR(255) NOT NULL,
    `warehouse_id` INT,
    `created_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (`warehouse_id`) REFERENCES `warehouses`(`id`) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

CREATE TABLE IF NOT EXISTS `nodes` (
    `id` INT AUTO_INCREMENT PRIMARY KEY,
    `name` VARCHAR(255) NOT NULL,
    `slot_id` INT,
    `created_at` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (`slot_id`) REFERENCES `slots`(`id`) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;

CREATE TABLE IF NOT EXISTS `sensor_readings` (
    `id` INT AUTO_INCREMENT PRIMARY KEY,
    `node_id` INT,
    `temperature` DECIMAL(5, 2),
    `humidity` DECIMAL(5, 2),
    `co2` INT,
    `gas_level` INT,
    `pressure` DECIMAL(6, 2),
    `light_level` INT,
    `timestamp` TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
    FOREIGN KEY (`node_id`) REFERENCES `nodes`(`id`) ON DELETE CASCADE
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4;