engine

type ColumnSpec struct {
	Name          string
	Type          string
	NotNull       bool
	Default       string
	PrimaryKey    bool
	UniqueTag     string
	AutoIncrement bool
	RenameFrom    string
}

type ConnectionConfig struct {
	Type                string        `json:"type" toml:"type"` // postgres、mysql、dameng、sqlite、kingbase
	Host                string        `json:"host" toml:"host"`
	Port                int           `json:"port" toml:"port"`
	Username            string        `json:"username" toml:"username"`
	Password            string        `json:"password" toml:"password"`
	DBName              string        `json:"dbname" toml:"dbname"`
	AdminDBName         string        `json:"admin_dbname" toml:"admin_dbname"`
	SSLMode             string        `json:"sslmode" toml:"sslmode"`
	MaxIdleConns        int           `json:"max_idle_conns" toml:"max_idle_conns"`
	MaxOpenConns        int           `json:"max_open_conns" toml:"max_open_conns"`
	ConnMaxLifetime     time.Duration `json:"conn_max_lifetime" toml:"conn_max_lifetime"`
	ConnMaxIdleTime     time.Duration `json:"conn_max_idle_time" toml:"conn_max_idle_time"`
	ConnectTimeout      time.Duration `json:"connect_timeout" toml:"connect_timeout"`
	ReadTimeout         time.Duration `json:"read_timeout" toml:"read_timeout"`
	WriteTimeout        time.Duration `json:"write_timeout" toml:"write_timeout"`
	HealthCheckInterval time.Duration `json:"health_check_interval" toml:"health_check_interval"`
	EnableQueryLog      bool          `json:"enable_query_log" toml:"enable_query_log"`
	SlowQueryTime       time.Duration `json:"slow_query_time" toml:"slow_query_time"`
	AutoCreate          bool          `json:"auto_create" toml:"auto_create"`
	Charset             string        `json:"charset" toml:"charset"` // MySQL/Dameng(MySQL mode):utf8mb4、Dameng(native):utf8、Postgres/Kingbase:UTF8
	Template            string        `json:"template" toml:"template"`
}

type Engine interface {
	Name() string
	DriverName() string
	BunDialect() schema.Dialect
	QuoteIdent(name string) string
	ClassifyError(err error) (bool, SQLError)
	Upsert(ctx context.Context, db bun.IDB, model interface{}, fields []string, duplicateKeys []string, duplicateValues map[string]interface{}) error
}

type IndexSpec struct {
	Name    string
	Columns []string
	Unique  bool
	System  bool
}

type LogLevel int

type Logger interface {
	SetLevel(LogLevel)
	Debug(ctx context.Context, msg string, fields ...interface{})
	Info(ctx context.Context, msg string, fields ...interface{})
	Warn(ctx context.Context, msg string, fields ...interface{})
	Error(ctx context.Context, msg string, fields ...interface{})
}

type Migration struct {
	bun.BaseModel `bun:"bun_migrations"`
	Version       string    `bun:"version,pk"`
	Name          string    `bun:"name"`
	AppliedAt     time.Time `bun:"applied_at"`
	Description   string    `bun:"description"`
}

type SQLError int

type SchemaEngine interface {
	Engine
	BuildDSN(cfg *ConnectionConfig) (string, error)
	EnsureDatabase(ctx context.Context, cfg *ConnectionConfig, logger Logger) error
	TableExists(ctx context.Context, db bun.IDB, table string) (bool, error)
	ListTables(ctx context.Context, db bun.IDB) (map[string]struct{}, error)
	ListColumns(ctx context.Context, db bun.IDB, table string) (map[string]ColumnSpec, error)
	ListColumnsAll(ctx context.Context, db bun.IDB) (map[string]map[string]ColumnSpec, error)
	ListColumnsSome(ctx context.Context, db bun.IDB, tables []string) (map[string]map[string]ColumnSpec, error)
	ListIndexes(ctx context.Context, db bun.IDB, table string) ([]IndexSpec, error)
	ListIndexesAll(ctx context.Context, db bun.IDB) (map[string][]IndexSpec, error)
	ListIndexesSome(ctx context.Context, db bun.IDB, tables []string) (map[string][]IndexSpec, error)
	AddColumnSQL(table string, c ColumnSpec) string
	ModifyColumnSQL(table string, c ColumnSpec) string
	RenameColumnSQL(table, oldName, newName string, c ColumnSpec) string
	DropColumnSQL(table, col string) string
	CreateIndexSQL(table string, idx IndexSpec) string
	DropIndexSQL(table string, idx IndexSpec) string
	RenameIndexSQL(table, oldName, newName string) string
	NormalizeSQLType(typ string) string
	NormalizeDefault(def string, nullable bool) string
	NormalizeDeclaredColumnType(typ string) string
	InferSQLType(rt reflect.Type) string
	NeedsModification(desired, existing ColumnSpec) bool
	// SupportsModifyAfterRename reports whether the planner should emit a
	// separate ModifyColumn operation right after renaming a column. The
	// PostgreSQL family needs it because RENAME COLUMN does not carry type
	// or default changes; mysql's CHANGE COLUMN redeclares the full column
	// definition itself, and dameng/sqlite keep the historical behavior of
	// skipping it.
	SupportsModifyAfterRename() bool
	InsertMigrationRecord(ctx context.Context, db bun.IDB, rec *Migration) error
	MigrationVersionExists(ctx context.Context, db bun.IDB, version string) (bool, error)
	SelectMigrationVersions(ctx context.Context, db bun.IDB, prefix string) ([]string, error)
	EnsureMigrationTableExists(ctx context.Context, db bun.IDB) error
}