package model

import (
	"context"
	"errors"

	mysqldriver "github.com/go-sql-driver/mysql"
	"gorm.io/gorm"

	"spark-server/internal/pkg/errs"
)

// Repo is MySQL persistence for groups / group_members (and conversation rows in the same txn).
type Repo struct {
	gdb *gorm.DB
}

func NewRepo(gdb *gorm.DB) *Repo {
	return &Repo{gdb: gdb}
}

func (m *Repo) session(ctx context.Context) (*gorm.DB, error) {
	if m == nil || m.gdb == nil {
		return nil, errs.ErrAvailable
	}
	return m.gdb.WithContext(ctx), nil
}

func mapDBErr(err error) error {
	if err == nil {
		return nil
	}
	if errors.Is(err, gorm.ErrRecordNotFound) {
		return errs.ErrNotFound
	}
	var me *mysqldriver.MySQLError
	if errors.As(err, &me) && me.Number == 1062 {
		return errs.ErrDuplicate
	}
	return errs.ErrInner.WithError("group-mysql", err)
}