-- AI对话表
CREATE TABLE IF NOT EXISTS `ai_conversations` (
    `id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT COMMENT '主键ID',
    `user_id` BIGINT UNSIGNED NOT NULL COMMENT '用户ID',
    `tenant_id` BIGINT UNSIGNED DEFAULT NULL COMMENT '租户ID',
    `title` VARCHAR(255) NOT NULL COMMENT '对话标题',
    `model` VARCHAR(100) DEFAULT NULL COMMENT 'AI模型',
    `service` VARCHAR(50) DEFAULT NULL COMMENT 'AI服务提供商',
    `status` VARCHAR(20) DEFAULT 'active' COMMENT '状态: active, archived, deleted',
    `message_count` INT UNSIGNED DEFAULT 0 COMMENT '消息数量',
    `total_tokens` BIGINT UNSIGNED DEFAULT 0 COMMENT '总Token数',
    `last_message_at` DATETIME DEFAULT NULL COMMENT '最后消息时间',
    `created_at` DATETIME DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
    `updated_at` DATETIME DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP COMMENT '更新时间',
    `deleted` TINYINT UNSIGNED DEFAULT 0 COMMENT '逻辑删除标记',
    PRIMARY KEY (`id`),
    KEY `idx_user_id` (`user_id`),
    KEY `idx_tenant_id` (`tenant_id`),
    KEY `idx_status` (`status`),
    KEY `idx_last_message_at` (`last_message_at`),
    KEY `idx_created_at` (`created_at`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci COMMENT='AI对话表';

-- AI消息表
CREATE TABLE IF NOT EXISTS `ai_messages` (
    `id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT COMMENT '主键ID',
    `conversation_id` BIGINT UNSIGNED NOT NULL COMMENT '对话ID',
    `role` VARCHAR(20) NOT NULL COMMENT '角色: user, assistant, system',
    `content` TEXT NOT NULL COMMENT '消息内容',
    `tokens` INT UNSIGNED DEFAULT 0 COMMENT 'Token数量',
    `created_at` DATETIME DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
    `deleted` TINYINT UNSIGNED DEFAULT 0 COMMENT '逻辑删除标记',
    PRIMARY KEY (`id`),
    KEY `idx_conversation_id` (`conversation_id`),
    KEY `idx_created_at` (`created_at`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci COMMENT='AI消息表';

-- AI使用记录表（可选，用于更详细的统计）
CREATE TABLE IF NOT EXISTS `ai_usage_logs` (
    `id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT COMMENT '主键ID',
    `user_id` BIGINT UNSIGNED NOT NULL COMMENT '用户ID',
    `tenant_id` BIGINT UNSIGNED DEFAULT NULL COMMENT '租户ID',
    `service` VARCHAR(50) NOT NULL COMMENT 'AI服务',
    `model` VARCHAR(100) NOT NULL COMMENT '模型',
    `request_type` VARCHAR(50) NOT NULL COMMENT '请求类型: chat, task, test',
    `input_tokens` INT UNSIGNED DEFAULT 0 COMMENT '输入Token数',
    `output_tokens` INT UNSIGNED DEFAULT 0 COMMENT '输出Token数',
    `total_tokens` INT UNSIGNED DEFAULT 0 COMMENT '总Token数',
    `response_time_ms` INT UNSIGNED DEFAULT 0 COMMENT '响应时间(毫秒)',
    `status` VARCHAR(20) DEFAULT 'success' COMMENT '状态: success, failed',
    `error_message` TEXT DEFAULT NULL COMMENT '错误信息',
    `created_at` DATETIME DEFAULT CURRENT_TIMESTAMP COMMENT '创建时间',
    PRIMARY KEY (`id`),
    KEY `idx_user_id` (`user_id`),
    KEY `idx_service_model` (`service`, `model`),
    KEY `idx_created_at` (`created_at`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci COMMENT='AI使用记录表';