//! Schema 定义和迁移
//!
//! 负责数据库表结构的创建和版本迁移。

use super::{lock_conn, Database, SCHEMA_VERSION};
use crate::error::AppError;
use rusqlite::Connection;

impl Database {
    /// 创建所有数据库表
    pub(crate) fn create_tables(&self) -> Result<(), AppError> {
        let conn = lock_conn!(self.conn);
        Self::create_tables_on_conn(&conn)
    }

    /// 在指定连接上创建表（供迁移和测试使用）
    pub(crate) fn create_tables_on_conn(conn: &Connection) -> Result<(), AppError> {
        // 1. Providers 表
        conn.execute(
            "CREATE TABLE IF NOT EXISTS providers (
                id TEXT NOT NULL,
                app_type TEXT NOT NULL,
                name TEXT NOT NULL,
                settings_config TEXT NOT NULL,
                website_url TEXT,
                category TEXT,
                created_at INTEGER,
                sort_index INTEGER,
                notes TEXT,
                icon TEXT,
                icon_color TEXT,
                meta TEXT NOT NULL DEFAULT '{}',
                is_current BOOLEAN NOT NULL DEFAULT 0,
                in_failover_queue BOOLEAN NOT NULL DEFAULT 0,
                PRIMARY KEY (id, app_type)
            )",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 2. Provider Endpoints 表
        conn.execute(
            "CREATE TABLE IF NOT EXISTS provider_endpoints (
                id INTEGER PRIMARY KEY AUTOINCREMENT,
                provider_id TEXT NOT NULL,
                app_type TEXT NOT NULL,
                url TEXT NOT NULL,
                added_at INTEGER,
                FOREIGN KEY (provider_id, app_type) REFERENCES providers(id, app_type) ON DELETE CASCADE
            )",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 3. MCP Servers 表
        conn.execute(
            "CREATE TABLE IF NOT EXISTS mcp_servers (
            id TEXT PRIMARY KEY, name TEXT NOT NULL, server_config TEXT NOT NULL,
            description TEXT, homepage TEXT, docs TEXT, tags TEXT NOT NULL DEFAULT '[]',
            enabled_claude BOOLEAN NOT NULL DEFAULT 0, enabled_codex BOOLEAN NOT NULL DEFAULT 0,
            enabled_gemini BOOLEAN NOT NULL DEFAULT 0, enabled_opencode BOOLEAN NOT NULL DEFAULT 0
        )",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 4. Prompts 表
        conn.execute("CREATE TABLE IF NOT EXISTS prompts (
            id TEXT NOT NULL, app_type TEXT NOT NULL, name TEXT NOT NULL, content TEXT NOT NULL,
            description TEXT, enabled BOOLEAN NOT NULL DEFAULT 1, created_at INTEGER, updated_at INTEGER,
            PRIMARY KEY (id, app_type)
        )", []).map_err(|e| AppError::Database(e.to_string()))?;

        // 5. Skills 表（v3.10.0+ 统一结构）
        conn.execute(
            "CREATE TABLE IF NOT EXISTS skills (
            id TEXT PRIMARY KEY,
            name TEXT NOT NULL,
            description TEXT,
            directory TEXT NOT NULL,
            repo_owner TEXT,
            repo_name TEXT,
            repo_branch TEXT DEFAULT 'main',
            readme_url TEXT,
            enabled_claude BOOLEAN NOT NULL DEFAULT 0,
            enabled_codex BOOLEAN NOT NULL DEFAULT 0,
            enabled_gemini BOOLEAN NOT NULL DEFAULT 0,
            enabled_opencode BOOLEAN NOT NULL DEFAULT 0,
            installed_at INTEGER NOT NULL DEFAULT 0
        )",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 6. Skill Repos 表
        conn.execute(
            "CREATE TABLE IF NOT EXISTS skill_repos (
            owner TEXT NOT NULL, name TEXT NOT NULL, branch TEXT NOT NULL DEFAULT 'main',
            enabled BOOLEAN NOT NULL DEFAULT 1, PRIMARY KEY (owner, name)
        )",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 7. Settings 表
        conn.execute(
            "CREATE TABLE IF NOT EXISTS settings (key TEXT PRIMARY KEY, value TEXT)",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 8. Proxy Config 表（三行结构，app_type 主键）
        conn.execute("CREATE TABLE IF NOT EXISTS proxy_config (
            app_type TEXT PRIMARY KEY CHECK (app_type IN ('claude','codex','gemini')),
            proxy_enabled INTEGER NOT NULL DEFAULT 0, listen_address TEXT NOT NULL DEFAULT '127.0.0.1',
            listen_port INTEGER NOT NULL DEFAULT 15721, enable_logging INTEGER NOT NULL DEFAULT 1,
            enabled INTEGER NOT NULL DEFAULT 0, auto_failover_enabled INTEGER NOT NULL DEFAULT 0,
            max_retries INTEGER NOT NULL DEFAULT 3, streaming_first_byte_timeout INTEGER NOT NULL DEFAULT 60,
            streaming_idle_timeout INTEGER NOT NULL DEFAULT 120, non_streaming_timeout INTEGER NOT NULL DEFAULT 600,
            circuit_failure_threshold INTEGER NOT NULL DEFAULT 4, circuit_success_threshold INTEGER NOT NULL DEFAULT 2,
            circuit_timeout_seconds INTEGER NOT NULL DEFAULT 60, circuit_error_rate_threshold REAL NOT NULL DEFAULT 0.6,
            circuit_min_requests INTEGER NOT NULL DEFAULT 10,
            default_cost_multiplier TEXT NOT NULL DEFAULT '1',
            pricing_model_source TEXT NOT NULL DEFAULT 'response',
            created_at TEXT NOT NULL DEFAULT (datetime('now')), updated_at TEXT NOT NULL DEFAULT (datetime('now'))
        )", []).map_err(|e| AppError::Database(e.to_string()))?;

        // 初始化三行数据（每应用不同默认值）
        //
        // 兼容旧数据库：
        // - 老版本 proxy_config 是单例表（没有 app_type 列），此时不能执行三行 seed insert；
        // - 旧表会在 apply_schema_migrations() 中迁移为三行结构后再插入。
        if Self::has_column(conn, "proxy_config", "app_type")? {
            conn.execute(
                "INSERT OR IGNORE INTO proxy_config (app_type, max_retries,
                streaming_first_byte_timeout, streaming_idle_timeout, non_streaming_timeout,
                circuit_failure_threshold, circuit_success_threshold, circuit_timeout_seconds,
                circuit_error_rate_threshold, circuit_min_requests)
                VALUES ('claude', 6, 90, 180, 600, 8, 3, 90, 0.7, 15)",
                [],
            )
            .map_err(|e| AppError::Database(e.to_string()))?;
            conn.execute(
                "INSERT OR IGNORE INTO proxy_config (app_type, max_retries,
                streaming_first_byte_timeout, streaming_idle_timeout, non_streaming_timeout,
                circuit_failure_threshold, circuit_success_threshold, circuit_timeout_seconds,
                circuit_error_rate_threshold, circuit_min_requests)
                VALUES ('codex', 3, 60, 120, 600, 4, 2, 60, 0.6, 10)",
                [],
            )
            .map_err(|e| AppError::Database(e.to_string()))?;
            conn.execute(
                "INSERT OR IGNORE INTO proxy_config (app_type, max_retries,
                streaming_first_byte_timeout, streaming_idle_timeout, non_streaming_timeout,
                circuit_failure_threshold, circuit_success_threshold, circuit_timeout_seconds,
                circuit_error_rate_threshold, circuit_min_requests)
                VALUES ('gemini', 5, 60, 120, 600, 4, 2, 60, 0.6, 10)",
                [],
            )
            .map_err(|e| AppError::Database(e.to_string()))?;
        }

        // 9. Provider Health 表
        conn.execute("CREATE TABLE IF NOT EXISTS provider_health (
            provider_id TEXT NOT NULL, app_type TEXT NOT NULL, is_healthy INTEGER NOT NULL DEFAULT 1,
            consecutive_failures INTEGER NOT NULL DEFAULT 0, last_success_at TEXT, last_failure_at TEXT,
            last_error TEXT, updated_at TEXT NOT NULL,
            PRIMARY KEY (provider_id, app_type),
            FOREIGN KEY (provider_id, app_type) REFERENCES providers(id, app_type) ON DELETE CASCADE
        )", []).map_err(|e| AppError::Database(e.to_string()))?;

        // 10. Proxy Request Logs 表
        conn.execute("CREATE TABLE IF NOT EXISTS proxy_request_logs (
            request_id TEXT PRIMARY KEY, provider_id TEXT NOT NULL, app_type TEXT NOT NULL, model TEXT NOT NULL,
            request_model TEXT,
            input_tokens INTEGER NOT NULL DEFAULT 0, output_tokens INTEGER NOT NULL DEFAULT 0,
            cache_read_tokens INTEGER NOT NULL DEFAULT 0, cache_creation_tokens INTEGER NOT NULL DEFAULT 0,
            input_cost_usd TEXT NOT NULL DEFAULT '0', output_cost_usd TEXT NOT NULL DEFAULT '0',
            cache_read_cost_usd TEXT NOT NULL DEFAULT '0', cache_creation_cost_usd TEXT NOT NULL DEFAULT '0',
            total_cost_usd TEXT NOT NULL DEFAULT '0', latency_ms INTEGER NOT NULL, first_token_ms INTEGER,
            duration_ms INTEGER, status_code INTEGER NOT NULL, error_message TEXT, session_id TEXT,
            provider_type TEXT, is_streaming INTEGER NOT NULL DEFAULT 0,
            cost_multiplier TEXT NOT NULL DEFAULT '1.0', created_at INTEGER NOT NULL
        )", []).map_err(|e| AppError::Database(e.to_string()))?;

        conn.execute("CREATE INDEX IF NOT EXISTS idx_request_logs_provider ON proxy_request_logs(provider_id, app_type)", [])
            .map_err(|e| AppError::Database(e.to_string()))?;
        conn.execute("CREATE INDEX IF NOT EXISTS idx_request_logs_created_at ON proxy_request_logs(created_at)", [])
            .map_err(|e| AppError::Database(e.to_string()))?;
        conn.execute(
            "CREATE INDEX IF NOT EXISTS idx_request_logs_model ON proxy_request_logs(model)",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;
        conn.execute(
            "CREATE INDEX IF NOT EXISTS idx_request_logs_session ON proxy_request_logs(session_id)",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;
        conn.execute(
            "CREATE INDEX IF NOT EXISTS idx_request_logs_status ON proxy_request_logs(status_code)",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 11. Model Pricing 表
        conn.execute(
            "CREATE TABLE IF NOT EXISTS model_pricing (
            model_id TEXT PRIMARY KEY, display_name TEXT NOT NULL,
            input_cost_per_million TEXT NOT NULL, output_cost_per_million TEXT NOT NULL,
            cache_read_cost_per_million TEXT NOT NULL DEFAULT '0',
            cache_creation_cost_per_million TEXT NOT NULL DEFAULT '0'
        )",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 12. Stream Check Logs 表
        conn.execute("CREATE TABLE IF NOT EXISTS stream_check_logs (
            id INTEGER PRIMARY KEY AUTOINCREMENT, provider_id TEXT NOT NULL, provider_name TEXT NOT NULL,
            app_type TEXT NOT NULL, status TEXT NOT NULL, success INTEGER NOT NULL, message TEXT NOT NULL,
            response_time_ms INTEGER, http_status INTEGER, model_used TEXT,
            retry_count INTEGER DEFAULT 0, tested_at INTEGER NOT NULL
        )", []).map_err(|e| AppError::Database(e.to_string()))?;

        conn.execute(
            "CREATE INDEX IF NOT EXISTS idx_stream_check_logs_provider
             ON stream_check_logs(app_type, provider_id, tested_at DESC)",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 注意：circuit_breaker_config 已合并到 proxy_config 表中

        // 16. Proxy Live Backup 表 (Live 配置备份)
        conn.execute(
            "CREATE TABLE IF NOT EXISTS proxy_live_backup (
            app_type TEXT PRIMARY KEY, original_config TEXT NOT NULL, backed_up_at TEXT NOT NULL
        )",
            [],
        )
        .map_err(|e| AppError::Database(e.to_string()))?;

        // 尝试添加 live_takeover_active 列到 proxy_config 表
        let _ = conn.execute(
            "ALTER TABLE proxy_config ADD COLUMN live_takeover_active INTEGER NOT NULL DEFAULT 0",
            [],
        );

        // 尝试添加基础配置列到 proxy_config 表（兼容 v3.9.0-2 升级）
        let _ = conn.execute(
            "ALTER TABLE proxy_config ADD COLUMN proxy_enabled INTEGER NOT NULL DEFAULT 0",
            [],
        );
        let _ = conn.execute(
            "ALTER TABLE proxy_config ADD COLUMN listen_address TEXT NOT NULL DEFAULT '127.0.0.1'",
            [],
        );
        let _ = conn.execute(
            "ALTER TABLE proxy_config ADD COLUMN listen_port INTEGER NOT NULL DEFAULT 15721",
            [],
        );
        let _ = conn.execute(
            "ALTER TABLE proxy_config ADD COLUMN enable_logging INTEGER NOT NULL DEFAULT 1",
            [],
        );

        // 尝试添加超时配置列到 proxy_config 表
        let _ = conn.execute(
            "ALTER TABLE proxy_config ADD COLUMN streaming_first_byte_timeout INTEGER NOT NULL DEFAULT 60",
            [],
        );
        let _ = conn.execute(
            "ALTER TABLE proxy_config ADD COLUMN streaming_idle_timeout INTEGER NOT NULL DEFAULT 120",
            [],
        );
        let _ = conn.execute(
            "ALTER TABLE proxy_config ADD COLUMN non_streaming_timeout INTEGER NOT NULL DEFAULT 600",
            [],
        );

        // 兼容：若旧版 proxy_config 仍为单例结构（无 app_type），则在启动时直接转换为三行结构
        // 说明：user_version=2 时不会再触发 v1->v2 迁移，但新代码查询依赖 app_type 列。
        if Self::table_exists(conn, "proxy_config")?
            && !Self::has_column(conn, "proxy_config", "app_type")?
        {
            Self::migrate_proxy_config_to_per_app(conn)?;
        }

        // 确保 in_failover_queue 列存在（对于已存在的 v2 数据库）
        Self::add_column_if_missing(
            conn,
            "providers",
            "in_failover_queue",
            "BOOLEAN NOT NULL DEFAULT 0",
        )?;

        // 删除旧的 failover_queue 表（如果存在）
        let _ = conn.execute("DROP INDEX IF EXISTS idx_failover_queue_order", []);
        let _ = conn.execute("DROP TABLE IF EXISTS failover_queue", []);

        // 为故障转移队列创建索引（基于 providers 表）
        let _ = conn.execute(
            "CREATE INDEX IF NOT EXISTS idx_providers_failover
             ON providers(app_type, in_failover_queue, sort_index)",
            [],
        );

        Ok(())
    }

    /// 应用 Schema 迁移
    pub(crate) fn apply_schema_migrations(&self) -> Result<(), AppError> {
        let conn = lock_conn!(self.conn);
        Self::apply_schema_migrations_on_conn(&conn)
    }

    /// 在指定连接上应用 Schema 迁移
    pub(crate) fn apply_schema_migrations_on_conn(conn: &Connection) -> Result<(), AppError> {
        conn.execute("SAVEPOINT schema_migration;", [])
            .map_err(|e| AppError::Database(format!("开启迁移 savepoint 失败: {e}")))?;

        let mut version = Self::get_user_version(conn)?;

        if version > SCHEMA_VERSION {
            conn.execute("ROLLBACK TO schema_migration;", []).ok();
            conn.execute("RELEASE schema_migration;", []).ok();
            return Err(AppError::Database(format!(
                "数据库版本过新（{version}），当前应用仅支持 {SCHEMA_VERSION}，请升级应用后再尝试。"
            )));
        }

        let result = (|| {
            while version < SCHEMA_VERSION {
                match version {
                    0 => {
                        log::info!("检测到 user_version=0，迁移到 1（补齐缺失列并设置版本）");
                        Self::migrate_v0_to_v1(conn)?;
                        Self::set_user_version(conn, 1)?;
                    }
                    1 => {
                        log::info!(
                            "迁移数据库从 v1 到 v2（添加使用统计表和完整字段，重构 skills 表）"
                        );
                        Self::migrate_v1_to_v2(conn)?;
                        Self::set_user_version(conn, 2)?;
                    }
                    2 => {
                        log::info!("迁移数据库从 v2 到 v3（Skills 统一管理架构）");
                        Self::migrate_v2_to_v3(conn)?;
                        Self::set_user_version(conn, 3)?;
                    }
                    3 => {
                        log::info!("迁移数据库从 v3 到 v4（OpenCode 支持）");
                        Self::migrate_v3_to_v4(conn)?;
                        Self::set_user_version(conn, 4)?;
                    }
                    4 => {
                        log::info!("迁移数据库从 v4 到 v5（计费模式支持）");
                        Self::migrate_v4_to_v5(conn)?;
                        Self::set_user_version(conn, 5)?;
                    }
                    _ => {
                        return Err(AppError::Database(format!(
                            "未知的数据库版本 {version}，无法迁移到 {SCHEMA_VERSION}"
                        )));
                    }
                }
                version = Self::get_user_version(conn)?;
            }
            Ok(())
        })();

        match result {
            Ok(_) => {
                conn.execute("RELEASE schema_migration;", [])
                    .map_err(|e| AppError::Database(format!("提交迁移 savepoint 失败: {e}")))?;
                Ok(())
            }
            Err(e) => {
                conn.execute("ROLLBACK TO schema_migration;", []).ok();
                conn.execute("RELEASE schema_migration;", []).ok();
                Err(e)
            }
        }
    }

    /// v0 -> v1 迁移：补齐所有缺失列
    fn migrate_v0_to_v1(conn: &Connection) -> Result<(), AppError> {
        // providers 表
        Self::add_column_if_missing(conn, "providers", "category", "TEXT")?;
        Self::add_column_if_missing(conn, "providers", "created_at", "INTEGER")?;
        Self::add_column_if_missing(conn, "providers", "sort_index", "INTEGER")?;
        Self::add_column_if_missing(conn, "providers", "notes", "TEXT")?;
        Self::add_column_if_missing(conn, "providers", "icon", "TEXT")?;
        Self::add_column_if_missing(conn, "providers", "icon_color", "TEXT")?;
        Self::add_column_if_missing(conn, "providers", "meta", "TEXT NOT NULL DEFAULT '{}'")?;
        Self::add_column_if_missing(
            conn,
            "providers",
            "is_current",
            "BOOLEAN NOT NULL DEFAULT 0",
        )?;

        // provider_endpoints 表
        Self::add_column_if_missing(conn, "provider_endpoints", "added_at", "INTEGER")?;

        // mcp_servers 表
        Self::add_column_if_missing(conn, "mcp_servers", "description", "TEXT")?;
        Self::add_column_if_missing(conn, "mcp_servers", "homepage", "TEXT")?;
        Self::add_column_if_missing(conn, "mcp_servers", "docs", "TEXT")?;
        Self::add_column_if_missing(conn, "mcp_servers", "tags", "TEXT NOT NULL DEFAULT '[]'")?;
        Self::add_column_if_missing(
            conn,
            "mcp_servers",
            "enabled_codex",
            "BOOLEAN NOT NULL DEFAULT 0",
        )?;
        Self::add_column_if_missing(
            conn,
            "mcp_servers",
            "enabled_gemini",
            "BOOLEAN NOT NULL DEFAULT 0",
        )?;

        // prompts 表
        Self::add_column_if_missing(conn, "prompts", "description", "TEXT")?;
        Self::add_column_if_missing(conn, "prompts", "enabled", "BOOLEAN NOT NULL DEFAULT 1")?;
        Self::add_column_if_missing(conn, "prompts", "created_at", "INTEGER")?;
        Self::add_column_if_missing(conn, "prompts", "updated_at", "INTEGER")?;

        // skills 表
        Self::add_column_if_missing(conn, "skills", "installed_at", "INTEGER NOT NULL DEFAULT 0")?;

        // skill_repos 表
        Self::add_column_if_missing(
            conn,
            "skill_repos",
            "branch",
            "TEXT NOT NULL DEFAULT 'main'",
        )?;
        Self::add_column_if_missing(conn, "skill_repos", "enabled", "BOOLEAN NOT NULL DEFAULT 1")?;
        // 注意: skills_path 字段已被移除，因为现在支持全仓库递归扫描

        Ok(())
    }

    /// v1 -> v2 迁移：添加使用统计表和完整字段，重构 skills 表
    fn migrate_v1_to_v2(conn: &Connection) -> Result<(), AppError> {
        // providers 表字段
        Self::add_column_if_missing(
            conn,
            "providers",
            "cost_multiplier",
            "TEXT NOT NULL DEFAULT '1.0'",
        )?;
        Self::add_column_if_missing(conn, "providers", "limit_daily_usd", "TEXT")?;
        Self::add_column_if_missing(conn, "providers", "limit_monthly_usd", "TEXT")?;
        Self::add_column_if_missing(conn, "providers", "provider_type", "TEXT")?;
        Self::add_column_if_missing(
            conn,
            "providers",
            "in_failover_queue",
            "BOOLEAN NOT NULL DEFAULT 0",
        )?;

        // 添加代理超时配置字段
        if Self::table_exists(conn, "proxy_config")? {
            // 兼容旧版本缺失的基础字段
            Self::add_column_if_missing(
                conn,
                "proxy_config",
                "proxy_enabled",
                "INTEGER NOT NULL DEFAULT 0",
            )?;
            Self::add_column_if_missing(
                conn,
                "proxy_config",
                "listen_address",
                "TEXT NOT NULL DEFAULT '127.0.0.1'",
            )?;
            Self::add_column_if_missing(
                conn,
                "proxy_config",
                "listen_port",
                "INTEGER NOT NULL DEFAULT 15721",
            )?;
            Self::add_column_if_missing(
                conn,
                "proxy_config",
                "enable_logging",
                "INTEGER NOT NULL DEFAULT 1",
            )?;

            Self::add_column_if_missing(
                conn,
                "proxy_config",
                "streaming_first_byte_timeout",
                "INTEGER NOT NULL DEFAULT 60",
            )?;
            Self::add_column_if_missing(
                conn,
                "proxy_config",
                "streaming_idle_timeout",
                "INTEGER NOT NULL DEFAULT 120",
            )?;
            Self::add_column_if_missing(
                conn,
                "proxy_config",
                "non_streaming_timeout",
                "INTEGER NOT NULL DEFAULT 600",
            )?;
        }

        // 删除旧的 failover_queue 表（如果存在）
        conn.execute("DROP INDEX IF EXISTS idx_failover_queue_order", [])
            .map_err(|e| AppError::Database(format!("删除 failover_queue 索引失败: {e}")))?;
        conn.execute("DROP TABLE IF EXISTS failover_queue", [])
            .map_err(|e| AppError::Database(format!("删除 failover_queue 表失败: {e}")))?;

        // 创建 failover 索引
        conn.execute(
            "CREATE INDEX IF NOT EXISTS idx_providers_failover
             ON providers(app_type, in_failover_queue, sort_index)",
            [],
        )
        .map_err(|e| AppError::Database(format!("创建 failover 索引失败: {e}")))?;

        // proxy_request_logs 表
        conn.execute("CREATE TABLE IF NOT EXISTS proxy_request_logs (
            request_id TEXT PRIMARY KEY, provider_id TEXT NOT NULL, app_type TEXT NOT NULL, model TEXT NOT NULL,
            request_model TEXT,
            input_tokens INTEGER NOT NULL DEFAULT 0, output_tokens INTEGER NOT NULL DEFAULT 0,
            cache_read_tokens INTEGER NOT NULL DEFAULT 0, cache_creation_tokens INTEGER NOT NULL DEFAULT 0,
            input_cost_usd TEXT NOT NULL DEFAULT '0', output_cost_usd TEXT NOT NULL DEFAULT '0',
            cache_read_cost_usd TEXT NOT NULL DEFAULT '0', cache_creation_cost_usd TEXT NOT NULL DEFAULT '0',
            total_cost_usd TEXT NOT NULL DEFAULT '0', latency_ms INTEGER NOT NULL, first_token_ms INTEGER,
            duration_ms INTEGER, status_code INTEGER NOT NULL, error_message TEXT, session_id TEXT,
            provider_type TEXT, is_streaming INTEGER NOT NULL DEFAULT 0,
            cost_multiplier TEXT NOT NULL DEFAULT '1.0', created_at INTEGER NOT NULL
        )", [])?;

        // 为已存在的表添加新字段
        Self::add_column_if_missing(conn, "proxy_request_logs", "provider_type", "TEXT")?;
        Self::add_column_if_missing(
            conn,
            "proxy_request_logs",
            "is_streaming",
            "INTEGER NOT NULL DEFAULT 0",
        )?;
        Self::add_column_if_missing(
            conn,
            "proxy_request_logs",
            "cost_multiplier",
            "TEXT NOT NULL DEFAULT '1.0'",
        )?;
        Self::add_column_if_missing(conn, "proxy_request_logs", "first_token_ms", "INTEGER")?;
        Self::add_column_if_missing(conn, "proxy_request_logs", "duration_ms", "INTEGER")?;

        // model_pricing 表
        conn.execute(
            "CREATE TABLE IF NOT EXISTS model_pricing (
            model_id TEXT PRIMARY KEY, display_name TEXT NOT NULL,
            input_cost_per_million TEXT NOT NULL, output_cost_per_million TEXT NOT NULL,
            cache_read_cost_per_million TEXT NOT NULL DEFAULT '0',
            cache_creation_cost_per_million TEXT NOT NULL DEFAULT '0'
        )",
            [],
        )?;

        // 清空并重新插入模型定价
        conn.execute("DELETE FROM model_pricing", [])
            .map_err(|e| AppError::Database(format!("清空模型定价失败: {e}")))?;
        Self::seed_model_pricing(conn)?;

        // 重构 skills 表（添加 app_type 字段）
        Self::migrate_skills_table(conn)?;

        // 重构 proxy_config 为三行结构（每应用独立配置）
        Self::migrate_proxy_config_to_per_app(conn)?;

        Ok(())
    }

    /// 将 proxy_config 迁移为三行结构（每应用独立配置）
    fn migrate_proxy_config_to_per_app(conn: &Connection) -> Result<(), AppError> {
        // 检查是否已经是新表结构（幂等性）
        if !Self::table_exists(conn, "proxy_config")? {
            // 表不存在，跳过迁移（新安装）
            return Ok(());
        }

        if Self::has_column(conn, "proxy_config", "app_type")? {
            // 已经是三行结构，跳过迁移
            log::info!("proxy_config 已经是三行结构，跳过迁移");
            return Ok(());
        }

        // 读取旧配置
        let old_config = conn
            .query_row(
                "SELECT listen_address, listen_port, max_retries, enable_logging,
                    streaming_first_byte_timeout, streaming_idle_timeout, non_streaming_timeout
             FROM proxy_config WHERE id = 1",
                [],
                |row| {
                    Ok((
                        row.get::<_, String>(0)?,
                        row.get::<_, i32>(1)?,
                        row.get::<_, i32>(2)?,
                        row.get::<_, i32>(3)?,
                        row.get::<_, i32>(4).unwrap_or(30),
                        row.get::<_, i32>(5).unwrap_or(60),
                        row.get::<_, i32>(6).unwrap_or(300),
                    ))
                },
            )
            .unwrap_or_else(|_| ("127.0.0.1".to_string(), 5000, 3, 1, 30, 60, 300));

        let old_cb = conn.query_row(
            "SELECT failure_threshold, success_threshold, timeout_seconds, error_rate_threshold, min_requests
             FROM circuit_breaker_config WHERE id = 1", [],
            |row| Ok((row.get::<_, i32>(0)?, row.get::<_, i32>(1)?, row.get::<_, i64>(2)?,
                      row.get::<_, f64>(3)?, row.get::<_, i32>(4)?))
        ).unwrap_or((5, 2, 60, 0.5, 10));

        let get_bool = |key: &str| -> bool {
            conn.query_row("SELECT value FROM settings WHERE key = ?", [key], |r| {
                r.get::<_, String>(0)
            })
            .map(|v| v == "true" || v == "1")
            .unwrap_or(false)
        };

        let apps = [
            (
                "claude",
                get_bool("proxy_takeover_claude"),
                get_bool("auto_failover_enabled_claude"),
                6,
                45,
                90,
                8,
                3,
                90,
                0.6,
                15,
            ),
            (
                "codex",
                get_bool("proxy_takeover_codex"),
                get_bool("auto_failover_enabled_codex"),
                3,
                old_config.4,
                old_config.5,
                old_cb.0,
                old_cb.1,
                old_cb.2,
                old_cb.3,
                old_cb.4,
            ),
            (
                "gemini",
                get_bool("proxy_takeover_gemini"),
                get_bool("auto_failover_enabled_gemini"),
                5,
                old_config.4,
                old_config.5,
                old_cb.0,
                old_cb.1,
                old_cb.2,
                old_cb.3,
                old_cb.4,
            ),
        ];

        // 创建新表
        conn.execute("DROP TABLE IF EXISTS proxy_config_new", [])?;
        conn.execute("CREATE TABLE proxy_config_new (
            app_type TEXT PRIMARY KEY CHECK (app_type IN ('claude','codex','gemini')),
            proxy_enabled INTEGER NOT NULL DEFAULT 0, listen_address TEXT NOT NULL DEFAULT '127.0.0.1',
            listen_port INTEGER NOT NULL DEFAULT 15721, enable_logging INTEGER NOT NULL DEFAULT 1,
            enabled INTEGER NOT NULL DEFAULT 0, auto_failover_enabled INTEGER NOT NULL DEFAULT 0,
            max_retries INTEGER NOT NULL DEFAULT 3, streaming_first_byte_timeout INTEGER NOT NULL DEFAULT 60,
            streaming_idle_timeout INTEGER NOT NULL DEFAULT 120, non_streaming_timeout INTEGER NOT NULL DEFAULT 600,
            circuit_failure_threshold INTEGER NOT NULL DEFAULT 4, circuit_success_threshold INTEGER NOT NULL DEFAULT 2,
            circuit_timeout_seconds INTEGER NOT NULL DEFAULT 60, circuit_error_rate_threshold REAL NOT NULL DEFAULT 0.6,
            circuit_min_requests INTEGER NOT NULL DEFAULT 10,
            default_cost_multiplier TEXT NOT NULL DEFAULT '1',
            pricing_model_source TEXT NOT NULL DEFAULT 'response',
            created_at TEXT NOT NULL DEFAULT (datetime('now')), updated_at TEXT NOT NULL DEFAULT (datetime('now'))
        )", [])?;

        // 插入三行配置
        for (app, takeover, failover, retries, fb, idle, cb_f, cb_s, cb_t, cb_r, cb_m) in apps {
            conn.execute(
                "INSERT INTO proxy_config_new (app_type, proxy_enabled, listen_address, listen_port, enable_logging,
                 enabled, auto_failover_enabled, max_retries, streaming_first_byte_timeout, streaming_idle_timeout,
                 non_streaming_timeout, circuit_failure_threshold, circuit_success_threshold, circuit_timeout_seconds,
                 circuit_error_rate_threshold, circuit_min_requests)
                 VALUES (?1, 0, ?2, ?3, ?4, ?5, ?6, ?7, ?8, ?9, ?10, ?11, ?12, ?13, ?14, ?15)",
                rusqlite::params![app, old_config.0, old_config.1, old_config.3,
                    if takeover { 1 } else { 0 }, if failover { 1 } else { 0 },
                    retries, fb, idle, old_config.6, cb_f, cb_s, cb_t, cb_r, cb_m]
            ).map_err(|e| AppError::Database(format!("插入 {app} 配置失败: {e}")))?;
        }

        // 替换表并清理
        conn.execute("DROP TABLE IF EXISTS proxy_config", [])?;
        conn.execute("ALTER TABLE proxy_config_new RENAME TO proxy_config", [])?;
        conn.execute("DROP TABLE IF EXISTS circuit_breaker_config", [])?;
        conn.execute("DELETE FROM settings WHERE key LIKE 'proxy_takeover_%'", [])?;
        conn.execute(
            "DELETE FROM settings WHERE key LIKE 'auto_failover_enabled_%'",
            [],
        )?;

        log::info!("proxy_config 已迁移为三行结构");
        Ok(())
    }

    /// 迁移 skills 表：从单 key 主键改为 (directory, app_type) 复合主键
    fn migrate_skills_table(conn: &Connection) -> Result<(), AppError> {
        // v3 结构（统一管理架构）已经是更高版本的 skills 表：
        // - 主键为 id
        // - 包含 enabled_claude / enabled_codex / enabled_gemini 等列
        // 在这种情况下，不应再执行 v1 -> v2 的迁移逻辑，否则会因列不匹配而失败。
        if Self::has_column(conn, "skills", "enabled_claude")?
            || Self::has_column(conn, "skills", "id")?
        {
            log::info!("skills 表已经是 v3 结构，跳过 v1 -> v2 迁移");
            return Ok(());
        }

        // 检查是否已经是新表结构
        if Self::has_column(conn, "skills", "app_type")? {
            log::info!("skills 表已经包含 app_type 字段，跳过迁移");
            return Ok(());
        }

        log::info!("开始迁移 skills 表...");

        // 1. 重命名旧表
        conn.execute("ALTER TABLE skills RENAME TO skills_old", [])
            .map_err(|e| AppError::Database(format!("重命名旧 skills 表失败: {e}")))?;

        // 2. 创建新表
        conn.execute(
            "CREATE TABLE skills (
                directory TEXT NOT NULL,
                app_type TEXT NOT NULL,
                installed BOOLEAN NOT NULL DEFAULT 0,
                installed_at INTEGER NOT NULL DEFAULT 0,
                PRIMARY KEY (directory, app_type)
            )",
            [],
        )
        .map_err(|e| AppError::Database(format!("创建新 skills 表失败: {e}")))?;

        // 3. 迁移数据：解析 key 格式（如 "claude:my-skill" 或 "codex:foo"）
        //    旧数据如果没有前缀，默认为 claude
        let mut stmt = conn
            .prepare("SELECT key, installed, installed_at FROM skills_old")
            .map_err(|e| AppError::Database(format!("查询旧 skills 数据失败: {e}")))?;

        let old_skills: Vec<(String, bool, i64)> = stmt
            .query_map([], |row| {
                Ok((
                    row.get::<_, String>(0)?,
                    row.get::<_, bool>(1)?,
                    row.get::<_, i64>(2)?,
                ))
            })
            .map_err(|e| AppError::Database(format!("读取旧 skills 数据失败: {e}")))?
            .collect::<Result<Vec<_>, _>>()
            .map_err(|e| AppError::Database(format!("解析旧 skills 数据失败: {e}")))?;

        let count = old_skills.len();

        for (key, installed, installed_at) in old_skills {
            // 解析 key: "app:directory" 或 "directory"（默认 claude）
            let (app_type, directory) = if let Some(idx) = key.find(':') {
                let (app, dir) = key.split_at(idx);
                (app.to_string(), dir[1..].to_string()) // 跳过冒号
            } else {
                ("claude".to_string(), key.clone())
            };

            conn.execute(
                "INSERT INTO skills (directory, app_type, installed, installed_at) VALUES (?1, ?2, ?3, ?4)",
                rusqlite::params![directory, app_type, installed, installed_at],
            )
            .map_err(|e| {
                AppError::Database(format!("迁移 skill {key} 到新表失败: {e}"))
            })?;
        }

        // 4. 删除旧表
        conn.execute("DROP TABLE skills_old", [])
            .map_err(|e| AppError::Database(format!("删除旧 skills 表失败: {e}")))?;

        log::info!("skills 表迁移完成，共迁移 {count} 条记录");
        Ok(())
    }

    /// v2 -> v3 迁移：Skills 统一管理架构
    ///
    /// 将 skills 表从 (directory, app_type) 复合主键结构迁移到统一的 id 主键结构，
    /// 支持三应用启用标志（enabled_claude, enabled_codex, enabled_gemini）。
    ///
    /// 迁移策略：
    /// 1. 旧数据库只存储安装记录，真正的 skill 文件在文件系统
    /// 2. 直接重建新表结构，后续由 SkillService 在首次启动时扫描文件系统重建数据
    fn migrate_v2_to_v3(conn: &Connection) -> Result<(), AppError> {
        // 检查是否已经是新结构（通过检查是否有 enabled_claude 列）
        if Self::has_column(conn, "skills", "enabled_claude")? {
            log::info!("skills 表已经是 v3 结构，跳过迁移");
            return Ok(());
        }

        log::info!("开始迁移 skills 表到 v3 结构（统一管理架构）...");

        // 1. 备份旧数据（用于日志）
        let old_count: i64 = conn
            .query_row("SELECT COUNT(*) FROM skills", [], |row| row.get(0))
            .unwrap_or(0);
        log::info!("旧 skills 表有 {old_count} 条记录");

        // 标记：需要在启动后从文件系统扫描并重建 Skills 数据
        // 说明：v3 结构将 Skills 的 SSOT 迁移到 ~/.cc-switch/skills/，
        // 旧表只存“安装记录”，无法直接无损迁移到新结构，因此改为启动后扫描 app 目录导入。
        let _ = conn.execute(
            "INSERT OR REPLACE INTO settings (key, value) VALUES ('skills_ssot_migration_pending', 'true')",
            [],
        );

        // 2. 删除旧表
        conn.execute("DROP TABLE IF EXISTS skills", [])
            .map_err(|e| AppError::Database(format!("删除旧 skills 表失败: {e}")))?;

        // 3. 创建新表
        conn.execute(
            "CREATE TABLE skills (
                id TEXT PRIMARY KEY,
                name TEXT NOT NULL,
                description TEXT,
                directory TEXT NOT NULL,
                repo_owner TEXT,
                repo_name TEXT,
                repo_branch TEXT DEFAULT 'main',
                readme_url TEXT,
                enabled_claude BOOLEAN NOT NULL DEFAULT 0,
                enabled_codex BOOLEAN NOT NULL DEFAULT 0,
                enabled_gemini BOOLEAN NOT NULL DEFAULT 0,
                installed_at INTEGER NOT NULL DEFAULT 0
            )",
            [],
        )
        .map_err(|e| AppError::Database(format!("创建新 skills 表失败: {e}")))?;

        log::info!(
            "skills 表已迁移到 v3 结构。\n\
             注意：旧的安装记录已清除，首次启动时将自动扫描文件系统重建数据。"
        );

        Ok(())
    }

    /// v3 -> v4 迁移：添加 OpenCode 支持
    ///
    /// 为 mcp_servers 和 skills 表添加 enabled_opencode 列。
    fn migrate_v3_to_v4(conn: &Connection) -> Result<(), AppError> {
        // 为 mcp_servers 表添加 enabled_opencode 列
        Self::add_column_if_missing(
            conn,
            "mcp_servers",
            "enabled_opencode",
            "BOOLEAN NOT NULL DEFAULT 0",
        )?;

        // 为 skills 表添加 enabled_opencode 列
        Self::add_column_if_missing(
            conn,
            "skills",
            "enabled_opencode",
            "BOOLEAN NOT NULL DEFAULT 0",
        )?;

        log::info!("v3 -> v4 迁移完成：已添加 OpenCode 支持");
        Ok(())
    }

    /// v4 -> v5 迁移：新增计费模式配置与请求模型字段
    fn migrate_v4_to_v5(conn: &Connection) -> Result<(), AppError> {
        if Self::table_exists(conn, "proxy_config")? {
            Self::add_column_if_missing(
                conn,
                "proxy_config",
                "default_cost_multiplier",
                "TEXT NOT NULL DEFAULT '1'",
            )?;
            Self::add_column_if_missing(
                conn,
                "proxy_config",
                "pricing_model_source",
                "TEXT NOT NULL DEFAULT 'response'",
            )?;
        }
        if Self::table_exists(conn, "proxy_request_logs")? {
            Self::add_column_if_missing(conn, "proxy_request_logs", "request_model", "TEXT")?;
        }

        log::info!("v4 -> v5 迁移完成：已添加计费模式与请求模型字段");
        Ok(())
    }

    /// 插入默认模型定价数据
    /// 格式: (model_id, display_name, input, output, cache_read, cache_creation)
    /// 注意: model_id 使用短横线格式（如 claude-haiku-4-5），与 API 返回的模型名称标准化后一致
    fn seed_model_pricing(conn: &Connection) -> Result<(), AppError> {
        let pricing_data = [
            // Claude 4.5 系列 (Latest Models)
            (
                "claude-opus-4-5-20251101",
                "Claude Opus 4.5",
                "5",
                "25",
                "0.50",
                "6.25",
            ),
            (
                "claude-sonnet-4-5-20250929",
                "Claude Sonnet 4.5",
                "3",
                "15",
                "0.30",
                "3.75",
            ),
            (
                "claude-haiku-4-5-20251001",
                "Claude Haiku 4.5",
                "1",
                "5",
                "0.10",
                "1.25",
            ),
            // Claude 4 系列 (Legacy Models)
            (
                "claude-opus-4-20250514",
                "Claude Opus 4",
                "15",
                "75",
                "1.50",
                "18.75",
            ),
            (
                "claude-opus-4-1-20250805",
                "Claude Opus 4.1",
                "15",
                "75",
                "1.50",
                "18.75",
            ),
            (
                "claude-sonnet-4-20250514",
                "Claude Sonnet 4",
                "3",
                "15",
                "0.30",
                "3.75",
            ),
            // Claude 3.5 系列
            (
                "claude-3-5-haiku-20241022",
                "Claude 3.5 Haiku",
                "0.80",
                "4",
                "0.08",
                "1",
            ),
            (
                "claude-3-5-sonnet-20241022",
                "Claude 3.5 Sonnet",
                "3",
                "15",
                "0.30",
                "3.75",
            ),
            // GPT-5.2 系列
            ("gpt-5.2", "GPT-5.2", "1.75", "14", "0.175", "0"),
            ("gpt-5.2-low", "GPT-5.2", "1.75", "14", "0.175", "0"),
            ("gpt-5.2-medium", "GPT-5.2", "1.75", "14", "0.175", "0"),
            ("gpt-5.2-high", "GPT-5.2", "1.75", "14", "0.175", "0"),
            ("gpt-5.2-xhigh", "GPT-5.2", "1.75", "14", "0.175", "0"),
            ("gpt-5.2-codex", "GPT-5.2 Codex", "1.75", "14", "0.175", "0"),
            (
                "gpt-5.2-codex-low",
                "GPT-5.2 Codex",
                "1.75",
                "14",
                "0.175",
                "0",
            ),
            (
                "gpt-5.2-codex-medium",
                "GPT-5.2 Codex",
                "1.75",
                "14",
                "0.175",
                "0",
            ),
            (
                "gpt-5.2-codex-high",
                "GPT-5.2 Codex",
                "1.75",
                "14",
                "0.175",
                "0",
            ),
            (
                "gpt-5.2-codex-xhigh",
                "GPT-5.2 Codex",
                "1.75",
                "14",
                "0.175",
                "0",
            ),
            // GPT-5.1 系列
            ("gpt-5.1", "GPT-5.1", "1.25", "10", "0.125", "0"),
            ("gpt-5.1-low", "GPT-5.1", "1.25", "10", "0.125", "0"),
            ("gpt-5.1-medium", "GPT-5.1", "1.25", "10", "0.125", "0"),
            ("gpt-5.1-high", "GPT-5.1", "1.25", "10", "0.125", "0"),
            ("gpt-5.1-minimal", "GPT-5.1", "1.25", "10", "0.125", "0"),
            ("gpt-5.1-codex", "GPT-5.1 Codex", "1.25", "10", "0.125", "0"),
            (
                "gpt-5.1-codex-mini",
                "GPT-5.1 Codex",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            (
                "gpt-5.1-codex-max",
                "GPT-5.1 Codex",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            (
                "gpt-5.1-codex-max-high",
                "GPT-5.1 Codex",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            (
                "gpt-5.1-codex-max-xhigh",
                "GPT-5.1 Codex",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            // GPT-5 系列
            ("gpt-5", "GPT-5", "1.25", "10", "0.125", "0"),
            ("gpt-5-low", "GPT-5", "1.25", "10", "0.125", "0"),
            ("gpt-5-medium", "GPT-5", "1.25", "10", "0.125", "0"),
            ("gpt-5-high", "GPT-5", "1.25", "10", "0.125", "0"),
            ("gpt-5-minimal", "GPT-5", "1.25", "10", "0.125", "0"),
            ("gpt-5-codex", "GPT-5 Codex", "1.25", "10", "0.125", "0"),
            ("gpt-5-codex-low", "GPT-5 Codex", "1.25", "10", "0.125", "0"),
            (
                "gpt-5-codex-medium",
                "GPT-5 Codex",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            (
                "gpt-5-codex-high",
                "GPT-5 Codex",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            (
                "gpt-5-codex-mini",
                "GPT-5 Codex",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            (
                "gpt-5-codex-mini-medium",
                "GPT-5 Codex",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            (
                "gpt-5-codex-mini-high",
                "GPT-5 Codex",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            // Gemini 3 系列
            (
                "gemini-3-pro-preview",
                "Gemini 3 Pro Preview",
                "2",
                "12",
                "0.2",
                "0",
            ),
            (
                "gemini-3-flash-preview",
                "Gemini 3 Flash Preview",
                "0.5",
                "3",
                "0.05",
                "0",
            ),
            // Gemini 2.5 系列
            (
                "gemini-2.5-pro",
                "Gemini 2.5 Pro",
                "1.25",
                "10",
                "0.125",
                "0",
            ),
            (
                "gemini-2.5-flash",
                "Gemini 2.5 Flash",
                "0.3",
                "2.5",
                "0.03",
                "0",
            ),
            // ====== 国产模型 (CNY/1M tokens) ======
            // Doubao (字节跳动)
            (
                "doubao-seed-code",
                "Doubao Seed Code",
                "1.20",
                "8.00",
                "0.24",
                "0",
            ),
            // DeepSeek 系列
            (
                "deepseek-v3.2",
                "DeepSeek V3.2",
                "2.00",
                "3.00",
                "0.40",
                "0",
            ),
            (
                "deepseek-v3.1",
                "DeepSeek V3.1",
                "4.00",
                "12.00",
                "0.80",
                "0",
            ),
            ("deepseek-v3", "DeepSeek V3", "2.00", "8.00", "0.40", "0"),
            // Kimi (月之暗面)
            (
                "kimi-k2-thinking",
                "Kimi K2 Thinking",
                "4.00",
                "16.00",
                "1.00",
                "0",
            ),
            ("kimi-k2-0905", "Kimi K2", "4.00", "16.00", "1.00", "0"),
            (
                "kimi-k2-turbo",
                "Kimi K2 Turbo",
                "8.00",
                "58.00",
                "1.00",
                "0",
            ),
            // MiniMax 系列
            ("minimax-m2.1", "MiniMax M2.1", "2.10", "8.40", "0.21", "0"),
            (
                "minimax-m2.1-lightning",
                "MiniMax M2.1 Lightning",
                "2.10",
                "16.80",
                "0.21",
                "0",
            ),
            ("minimax-m2", "MiniMax M2", "2.10", "8.40", "0.21", "0"),
            // GLM (智谱)
            ("glm-4.7", "GLM-4.7", "2.00", "8.00", "0.40", "0"),
            ("glm-4.6", "GLM-4.6", "2.00", "8.00", "0.40", "0"),
            // Mimo (小米)
            ("mimo-v2-flash", "Mimo V2 Flash", "0", "0", "0", "0"),
        ];

        for (model_id, display_name, input, output, cache_read, cache_creation) in pricing_data {
            conn.execute(
                "INSERT OR REPLACE INTO model_pricing (
                    model_id, display_name, input_cost_per_million, output_cost_per_million,
                    cache_read_cost_per_million, cache_creation_cost_per_million
                ) VALUES (?1, ?2, ?3, ?4, ?5, ?6)",
                rusqlite::params![
                    model_id,
                    display_name,
                    input,
                    output,
                    cache_read,
                    cache_creation
                ],
            )
            .map_err(|e| AppError::Database(format!("插入模型定价失败: {e}")))?;
        }

        log::info!("已插入 {} 条默认模型定价数据", pricing_data.len());
        Ok(())
    }

    /// 确保模型定价表具备默认数据
    pub fn ensure_model_pricing_seeded(&self) -> Result<(), AppError> {
        let conn = lock_conn!(self.conn);
        Self::ensure_model_pricing_seeded_on_conn(&conn)
    }

    fn ensure_model_pricing_seeded_on_conn(conn: &Connection) -> Result<(), AppError> {
        let count: i64 = conn
            .query_row("SELECT COUNT(*) FROM model_pricing", [], |row| row.get(0))
            .map_err(|e| AppError::Database(format!("统计模型定价数据失败: {e}")))?;

        if count == 0 {
            Self::seed_model_pricing(conn)?;
        }
        Ok(())
    }

    // --- 辅助方法 ---

    pub(crate) fn get_user_version(conn: &Connection) -> Result<i32, AppError> {
        conn.query_row("PRAGMA user_version;", [], |row| row.get(0))
            .map_err(|e| AppError::Database(format!("读取 user_version 失败: {e}")))
    }

    pub(crate) fn set_user_version(conn: &Connection, version: i32) -> Result<(), AppError> {
        if version < 0 {
            return Err(AppError::Database("user_version 不能为负数".to_string()));
        }
        let sql = format!("PRAGMA user_version = {version};");
        conn.execute(&sql, [])
            .map_err(|e| AppError::Database(format!("写入 user_version 失败: {e}")))?;
        Ok(())
    }

    fn validate_identifier(s: &str, kind: &str) -> Result<(), AppError> {
        if s.is_empty() {
            return Err(AppError::Database(format!("{kind} 不能为空")));
        }
        if !s.chars().all(|c| c.is_ascii_alphanumeric() || c == '_') {
            return Err(AppError::Database(format!(
                "非法{kind}: {s}，仅允许字母、数字和下划线"
            )));
        }
        Ok(())
    }

    pub(crate) fn table_exists(conn: &Connection, table: &str) -> Result<bool, AppError> {
        Self::validate_identifier(table, "表名")?;

        let mut stmt = conn
            .prepare("SELECT name FROM sqlite_master WHERE type='table'")
            .map_err(|e| AppError::Database(format!("读取表名失败: {e}")))?;
        let mut rows = stmt
            .query([])
            .map_err(|e| AppError::Database(format!("查询表名失败: {e}")))?;
        while let Some(row) = rows.next().map_err(|e| AppError::Database(e.to_string()))? {
            let name: String = row
                .get(0)
                .map_err(|e| AppError::Database(format!("解析表名失败: {e}")))?;
            if name.eq_ignore_ascii_case(table) {
                return Ok(true);
            }
        }
        Ok(false)
    }

    pub(crate) fn has_column(
        conn: &Connection,
        table: &str,
        column: &str,
    ) -> Result<bool, AppError> {
        Self::validate_identifier(table, "表名")?;
        Self::validate_identifier(column, "列名")?;

        let sql = format!("PRAGMA table_info(\"{table}\");");
        let mut stmt = conn
            .prepare(&sql)
            .map_err(|e| AppError::Database(format!("读取表结构失败: {e}")))?;
        let mut rows = stmt
            .query([])
            .map_err(|e| AppError::Database(format!("查询表结构失败: {e}")))?;
        while let Some(row) = rows.next().map_err(|e| AppError::Database(e.to_string()))? {
            let name: String = row
                .get(1)
                .map_err(|e| AppError::Database(format!("读取列名失败: {e}")))?;
            if name.eq_ignore_ascii_case(column) {
                return Ok(true);
            }
        }
        Ok(false)
    }

    fn add_column_if_missing(
        conn: &Connection,
        table: &str,
        column: &str,
        definition: &str,
    ) -> Result<bool, AppError> {
        Self::validate_identifier(table, "表名")?;
        Self::validate_identifier(column, "列名")?;

        if !Self::table_exists(conn, table)? {
            return Err(AppError::Database(format!(
                "表 {table} 不存在，无法添加列 {column}"
            )));
        }
        if Self::has_column(conn, table, column)? {
            return Ok(false);
        }

        let sql = format!("ALTER TABLE \"{table}\" ADD COLUMN \"{column}\" {definition};");
        conn.execute(&sql, [])
            .map_err(|e| AppError::Database(format!("为表 {table} 添加列 {column} 失败: {e}")))?;
        log::info!("已为表 {table} 添加缺失列 {column}");
        Ok(true)
    }
}
