package errs

import (
	"database/sql"
	"errors"
	"log"

	sqlite3 "github.com/mattn/go-sqlite3"
)

func DB(err error) error {
	if err == nil {
		return nil
	}

	var e *Error
	if errors.As(err, &e) {
		return err
	}

	if errors.Is(err, sql.ErrNoRows) {
		return ErrNotFound
	}

	var se sqlite3.Error
	if errors.As(err, &se) {
		switch se.ExtendedCode {
		case sqlite3.ErrConstraintUnique, sqlite3.ErrConstraintPrimaryKey:
			return ErrAlreadyExists
		case sqlite3.ErrConstraintForeignKey, sqlite3.ErrConstraintCheck:
			return ErrConstraint
		}
	}

	log.Printf("Unexpected error: %v", err)
	return ErrUnexpected
}