package repositoryservices

import (
	"context"
	"database/sql"
	"errors"

	"git.jamestombleson.com/jtom38/newsbot-api/internal/entity"
	"git.jamestombleson.com/jtom38/newsbot-api/internal/repository"
	"github.com/google/uuid"
)

const (
	ErrUnexpectedAmountOfRowsUpdated = "got a unexpected of rows updated"
)

type RefreshToken interface {
	Create(ctx context.Context, username string) (string, error)
	GetByName(ctx context.Context, name string) (entity.RefreshTokenEntity, error)
	Delete(ctx context.Context, id int64) (int64, error)
	IsRequestValid(ctx context.Context, username, refreshToken string) error
}

// A new jwt token can be made if the user has the correct refresh token for the user.
// It will also require the old JWT token so the expire time is pulled and part of the validation
type RefreshTokenService struct {
	table repository.RefreshTokenRepository
}

func NewRefreshTokenService(conn *sql.DB) RefreshTokenService {
	return RefreshTokenService{
		table: repository.NewRefreshTokenRepository(conn),
	}
}

func (rt RefreshTokenService) Create(ctx context.Context, username string) (string, error) {
	//if a refresh token already exists for a user, reuse
	existingToken, err := rt.GetByName(ctx, username)
	if err == nil {
		rowsRemoved, err := rt.Delete(ctx, existingToken.ID)
		if err != nil {
			return "", err
		}

		if rowsRemoved != 1 {
			return "", errors.New(ErrUnexpectedAmountOfRowsUpdated)
		}
	}

	token, err := uuid.NewV7()
	if err != nil {
		return "", err
	}

	rows, err := rt.table.Create(ctx, username, token.String())
	if err != nil {
		return "", err
	}

	if rows != 1 {
		return "", errors.New("expected one row but got none")
	}
	return token.String(), nil
}

// Find the saved refresh token for a user and return it if it exists
func (rt RefreshTokenService) GetByName(ctx context.Context, name string) (entity.RefreshTokenEntity, error) {
	return rt.table.GetByUsername(ctx, name)
}

// This will request that a object is removed from the database
func (rt RefreshTokenService) Delete(ctx context.Context, id int64) (int64, error) {
	return rt.table.DeleteById(ctx, id)
}

func (rt RefreshTokenService) IsRequestValid(ctx context.Context, username, refreshToken string) error {
	token, err := rt.GetByName(ctx, username)
	if err != nil {
		return err
	}

	if token.Token != refreshToken {
		return errors.New("the refresh token given does not match")
	}

	return nil
}