db

type Column struct {
	Name     string
	Position int
	Default  *string
	// Nullable isn't supported for ClickHouse.
	Nullable bool
	Type     string
	// CharacterSet isn't supported for Postgres, ClickHouse, SQLite.
	CharacterSet string
	// Collation isn't supported for ClickHouse, SQLite.
	Collation string
	// Comment isn't supported for SQLite.
	Comment string
}

type ConnectionConfig struct {
	Host      string
	Port      string
	Username  string
	Password  string
	Database  string
	TLSConfig TLSConfig
	// ReadOnly is only supported for Postgres at the moment.
	ReadOnly bool
}

type ConnectionContext struct {
	EnvironmentName string
	InstanceName    string
}

type Driver interface {
	// A driver might support multiple engines (e.g. MySQL driver can support both MySQL and TiDB),
	// So we pass the dbType to tell the exact engine.
	Open(ctx context.Context, dbType Type, config ConnectionConfig, connCtx ConnectionContext) (Driver, error)
	// Remember to call Close to avoid connection leak
	Close(ctx context.Context) error
	Ping(ctx context.Context) error
	GetDbConnection(ctx context.Context, database string) (*sql.DB, error)
	GetVersion(ctx context.Context) (string, error)
	SyncSchema(ctx context.Context) ([]*User, []*Schema, error)
	Execute(ctx context.Context, statement string, useTransaction bool) error
	// Used for execute readonly SELECT statement
	// limit is the maximum row count returned. No limit enforced if limit <= 0
	Query(ctx context.Context, statement string, limit int) ([]interface{}, error)

	// Migration related
	// Check whether we need to setup migration (e.g. creating/upgrading the migration related tables)
	NeedsSetupMigration(ctx context.Context) (bool, error)
	// Create or upgrade migration related tables
	SetupMigrationIfNeeded(ctx context.Context) error
	// Execute migration will apply the statement and record the migration history, the schema after migration on success.
	// The migration type is determined by m.Type. Note, it can also perform data migration (DML) in addition to schema migration (DDL).
	// It returns the migration history id and the schema after migration on success.
	ExecuteMigration(ctx context.Context, m *MigrationInfo, statement string) (int64, string, error)
	// Find the migration history list and return most recent item first.
	FindMigrationHistoryList(ctx context.Context, find *MigrationHistoryFind) ([]*MigrationHistory, error)

	// Dump and restore
	// Dump the database, if dbName is empty, then dump all databases.
	Dump(ctx context.Context, database string, out io.Writer, schemaOnly bool) error
	// Restore the database from sc.
	Restore(ctx context.Context, sc *bufio.Scanner) error
}

type DriverConfig struct {
	Logger *zap.Logger
}

type Index struct {
	Name string
	// This could refer to a column or an expression
	Expression string
	Position   int
	// Type isn't supported for SQLite.
	Type   string
	Unique bool
	// Visible isn't supported for Postgres, SQLite.
	Visible bool
	// Comment isn't supported for SQLite.
	Comment string
}

type MigrationHistory struct {
	ID int

	Creator   string
	CreatedTs int64
	Updater   string
	UpdatedTs int64

	ReleaseVersion      string
	Namespace           string
	Sequence            int
	Source              MigrationSource
	Type                MigrationType
	Status              MigrationStatus
	Version             string
	Description         string
	Statement           string
	Schema              string
	SchemaPrev          string
	ExecutionDurationNs int64
	IssueID             string
	Payload             string
}

type MigrationHistoryFind struct {
	ID *int

	Database *string
	Source   *MigrationSource
	Version  *string
	// If specified, then it will only fetch "Limit" most recent migration histories
	Limit *int
}

type MigrationInfo struct {
	ReleaseVersion string
	Version        string
	Namespace      string
	Database       string
	Environment    string
	Source         MigrationSource
	Type           MigrationType
	Status         MigrationStatus
	Description    string
	Creator        string
	IssueID        string
	Payload        string
	CreateDatabase bool
}

type MigrationInfoPayload struct {
	VCSPushEvent *vcs.PushEvent `json:"pushEvent,omitempty"`
}

type MigrationSource string

type MigrationStatus string

type MigrationType string

type Schema struct {
	Name string
	// CharacterSet isn't supported for ClickHouse, Snowflake.
	CharacterSet string
	// Collation isn't supported for ClickHouse, Snowflake.
	Collation string
	UserList  []User
	TableList []Table
	ViewList  []View
}

type TLSConfig struct {
	SslCA   string
	SslCert string
	SslKey  string
}

type Table struct {
	Name string
	// CreatedTs isn't supported for ClickHouse, SQLite.
	CreatedTs int64
	// UpdatedTs isn't supported for SQLite.
	UpdatedTs int64
	Type      string
	// Engine isn't supported for Postgres, Snowflake, SQLite.
	Engine string
	// Collation isn't supported for Postgres, ClickHouse, Snowflake, SQLite.
	Collation string
	RowCount  int64
	// DataSize isn't supported for SQLite.
	DataSize int64
	// IndexSize isn't supported for ClickHouse, Snowflake, SQLite.
	IndexSize int64
	// DataFree isn't supported for Postgres, ClickHouse, Snowflake, SQLite.
	DataFree int64
	// CreateOptions isn't supported for Postgres, ClickHouse, Snowflake, SQLite.
	CreateOptions string
	// Comment isn't supported for SQLite.
	Comment    string
	ColumnList []Column
	// IndexList isn't supported for ClickHouse, Snowflake.
	IndexList []Index
}

type Type string

type User struct {
	Name  string
	Grant string
}

type View struct {
	Name string
	// CreatedTs isn't supported for ClickHouse.
	CreatedTs  int64
	UpdatedTs  int64
	Definition string
	Comment    string
}