package usersrv

import (
	"context"
	"errors"
	"time"

	"github.com/gofrs/uuid/v5"
	"github.com/olexsmir/onasty/internal/dtos"
	"github.com/olexsmir/onasty/internal/hasher"
	"github.com/olexsmir/onasty/internal/jwtutil"
	"github.com/olexsmir/onasty/internal/models"
	"github.com/olexsmir/onasty/internal/store/psql/sessionrepo"
	"github.com/olexsmir/onasty/internal/store/psql/userepo"
)

type UserServicer interface {
	SignUp(ctx context.Context, inp dtos.CreateUserDTO) (uuid.UUID, error)
	SignIn(ctx context.Context, inp dtos.SignInDTO) (dtos.TokensDTO, error)
	RefreshTokens(ctx context.Context, refreshToken string) (dtos.TokensDTO, error)
	Logout(ctx context.Context, userID uuid.UUID) error

	ParseToken(token string) (jwtutil.Payload, error)
	CheckIfUserExists(ctx context.Context, userID uuid.UUID) (bool, error)
}

var _ UserServicer = (*UserSrv)(nil)

type UserSrv struct {
	userstore    userepo.UserStorer
	sessionstore sessionrepo.SessionStorer
	hasher       hasher.Hasher
	jwtTokenizer jwtutil.JWTTokenizer

	refreshTokenExpiredAt time.Time
}

func New(
	userstore userepo.UserStorer,
	sessionstore sessionrepo.SessionStorer,
	hasher hasher.Hasher,
	jwtTokenizer jwtutil.JWTTokenizer,
) UserServicer {
	return &UserSrv{
		userstore:    userstore,
		sessionstore: sessionstore,
		hasher:       hasher,
		jwtTokenizer: jwtTokenizer,
	}
}

func (u *UserSrv) SignUp(ctx context.Context, inp dtos.CreateUserDTO) (uuid.UUID, error) {
	hashedPassword, err := u.hasher.Hash(inp.Password)
	if err != nil {
		return uuid.UUID{}, err
	}

	return u.userstore.Create(ctx, dtos.CreateUserDTO{
		Username:    inp.Username,
		Email:       inp.Email,
		Password:    hashedPassword,
		CreatedAt:   inp.CreatedAt,
		LastLoginAt: inp.LastLoginAt,
	})
}

func (u *UserSrv) SignIn(ctx context.Context, inp dtos.SignInDTO) (dtos.TokensDTO, error) {
	hashedPassword, err := u.hasher.Hash(inp.Password)
	if err != nil {
		return dtos.TokensDTO{}, err
	}

	user, err := u.userstore.GetUserByCredentials(ctx, inp.Email, hashedPassword)
	if err != nil {
		if errors.Is(err, models.ErrUserNotFound) {
			return dtos.TokensDTO{}, models.ErrUserWrongCredentials
		}
		return dtos.TokensDTO{}, err
	}

	tokens, err := u.getTokens(user.ID)
	if err != nil {
		return dtos.TokensDTO{}, err
	}

	if err := u.sessionstore.Set(ctx, user.ID, tokens.Refresh, u.refreshTokenExpiredAt); err != nil {
		return dtos.TokensDTO{}, err
	}

	return dtos.TokensDTO{
		Access:  tokens.Access,
		Refresh: tokens.Refresh,
	}, nil
}

func (u *UserSrv) Logout(ctx context.Context, userID uuid.UUID) error {
	return u.sessionstore.Delete(ctx, userID)
}

func (u *UserSrv) RefreshTokens(ctx context.Context, rtoken string) (dtos.TokensDTO, error) {
	userID, err := u.sessionstore.GetUserIDByRefreshToken(ctx, rtoken)
	if err != nil {
		return dtos.TokensDTO{}, err
	}

	tokens, err := u.getTokens(userID)
	if err != nil {
		return dtos.TokensDTO{}, err
	}

	err = u.sessionstore.Update(ctx, userID, rtoken, tokens.Refresh)

	return dtos.TokensDTO{
		Access:  tokens.Access,
		Refresh: tokens.Refresh,
	}, err
}

func (u *UserSrv) ParseToken(token string) (jwtutil.Payload, error) {
	return u.jwtTokenizer.Parse(token)
}

func (u UserSrv) CheckIfUserExists(ctx context.Context, id uuid.UUID) (bool, error) {
	return u.userstore.CheckIfUserExists(ctx, id)
}

func (u UserSrv) getTokens(userID uuid.UUID) (dtos.TokensDTO, error) {
	accessToken, err := u.jwtTokenizer.AccessToken(jwtutil.Payload{UserID: userID.String()})
	if err != nil {
		return dtos.TokensDTO{}, err
	}

	refreshToken, err := u.jwtTokenizer.RefreshToken()
	if err != nil {
		return dtos.TokensDTO{}, err
	}

	return dtos.TokensDTO{
		Access:  accessToken,
		Refresh: refreshToken,
	}, err
}