package postgresql

import (
	"context"
	"database/sql"
	"fmt"

	"github.com/jmoiron/sqlx"
	"go.temporal.io/server/common/config"
	"go.temporal.io/server/common/persistence/schema"
	"go.temporal.io/server/common/persistence/sql/sqlplugin"
	"go.temporal.io/server/common/persistence/sql/sqlplugin/postgresql/driver"
	"go.temporal.io/server/common/resolver"
	postgresqlschemaV12 "go.temporal.io/server/schema/postgresql/v12"
)

func (pdb *db) IsDupEntryError(err error) bool {
	return pdb.dbDriver.IsDupEntryError(err)
}

func (pdb *db) IsDupDatabaseError(err error) bool {
	return pdb.dbDriver.IsDupDatabaseError(err)
}

// db represents a logical connection to postgresql database
type db struct {
	dbKind   sqlplugin.DbKind
	dbName   string
	dbDriver driver.Driver

	plugin    *plugin
	cfg       *config.SQL
	resolver  resolver.ServiceResolver
	converter DataConverter

	handle *sqlplugin.DatabaseHandle
	tx     *sqlx.Tx
}

var _ sqlplugin.DB = (*db)(nil)

// newDB returns an instance of DB, which is a logical
// connection to the underlying postgresql database
func newDB(
	dbKind sqlplugin.DbKind,
	dbName string,
	dbDriver driver.Driver,
	handle *sqlplugin.DatabaseHandle,
	tx *sqlx.Tx,
) *db {
	mdb := &db{
		dbKind:   dbKind,
		dbName:   dbName,
		dbDriver: dbDriver,
		handle:   handle,
		tx:       tx,
	}
	mdb.converter = &converter{}
	return mdb
}

func (pdb *db) conn() sqlplugin.Conn {
	if pdb.tx != nil {
		return pdb.tx
	}
	return pdb.handle.Conn()
}

// BeginTx starts a new transaction and returns a reference to the Tx object
func (pdb *db) BeginTx(ctx context.Context) (sqlplugin.Tx, error) {
	db, err := pdb.handle.DB()
	if err != nil {
		// This error needs no conversion
		return nil, err
	}
	tx, err := db.BeginTxx(ctx, nil)
	if err != nil {
		return nil, pdb.handle.ConvertError(err)
	}
	return newDB(pdb.dbKind, pdb.dbName, pdb.dbDriver, pdb.handle, tx), nil
}

// Close closes the connection to the mysql db
func (pdb *db) Close() error {
	pdb.handle.Close()
	return nil
}

// PluginName returns the name of the mysql plugin
func (pdb *db) PluginName() string {
	return PluginName
}

// DbName returns the name of the database
func (pdb *db) DbName() string {
	return pdb.dbName
}

// ExpectedVersion returns expected version.
func (pdb *db) ExpectedVersion() string {
	switch pdb.dbKind {
	case sqlplugin.DbKindMain:
		return postgresqlschemaV12.Version
	case sqlplugin.DbKindVisibility:
		return postgresqlschemaV12.VisibilityVersion
	default:
		panic(fmt.Sprintf("unknown db kind %v", pdb.dbKind))
	}
}

// VerifyVersion verify schema version is up to date
func (pdb *db) VerifyVersion() error {
	expectedVersion := pdb.ExpectedVersion()
	return schema.VerifyCompatibleVersion(pdb, pdb.dbName, expectedVersion)
}

// Commit commits a previously started transaction
func (pdb *db) Commit() error {
	return pdb.tx.Commit()
}

// Rollback triggers rollback of a previously started transaction
func (pdb *db) Rollback() error {
	return pdb.tx.Rollback()
}

// Helper methods to hide common error handling
func (pdb *db) ExecContext(ctx context.Context, stmt string, args ...any) (sql.Result, error) {
	res, err := pdb.conn().ExecContext(ctx, stmt, args...)
	return res, pdb.handle.ConvertError(err)
}

func (pdb *db) GetContext(ctx context.Context, dest any, query string, args ...any) error {
	err := pdb.conn().GetContext(ctx, dest, query, args...)
	return pdb.handle.ConvertError(err)
}

func (pdb *db) Select(dest any, query string, args ...any) error {
	db, err := pdb.handle.DB()
	if err != nil {
		return err
	}
	err = db.Select(dest, query, args...)
	return pdb.handle.ConvertError(err)
}

func (pdb *db) SelectContext(ctx context.Context, dest any, query string, args ...any) error {
	err := pdb.conn().SelectContext(ctx, dest, query, args...)
	return pdb.handle.ConvertError(err)
}

func (pdb *db) NamedExecContext(ctx context.Context, query string, arg any) (sql.Result, error) {
	res, err := pdb.conn().NamedExecContext(ctx, query, arg)
	return res, pdb.handle.ConvertError(err)
}

func (pdb *db) PrepareNamedContext(ctx context.Context, query string) (*sqlx.NamedStmt, error) {
	stmt, err := pdb.conn().PrepareNamedContext(ctx, query)
	return stmt, pdb.handle.ConvertError(err)
}

func (pdb *db) QueryContext(ctx context.Context, query string, args ...any) (*sql.Rows, error) {
	db, err := pdb.handle.DB()
	if err != nil {
		return nil, err
	}
	rows, err := db.QueryContext(ctx, query, args...)
	return rows, pdb.handle.ConvertError(err)
}

func (pdb *db) Rebind(query string) string {
	return pdb.conn().Rebind(query)
}