package db

import (
	"crypto/rand"
	"encoding/base64"
	"farga/db/types"
	"farga/lib"
	"time"

	"github.com/google/uuid"
	"golang.org/x/oauth2"
)

// gets an oauth state from the token
func (db *DB) OAuthState(token string) (types.OAuthState, error) {
	var state types.OAuthState
	err := db.First(&state, "state = ?", token).Error
	return state, err
}

// creates an OAuth state.
func (db *DB) CreateOAuthState(id uuid.UUID) (*types.OAuthState, error) {
	b := make([]byte, 32)
	if _, err := rand.Read(b); err != nil {
		return nil, err
	}

	state := base64.RawURLEncoding.EncodeToString(b)
	verifier := oauth2.GenerateVerifier()

	oauthState := &types.OAuthState{
		State:     state,
		Verifier:  verifier,
		ExpiresAt: time.Now().Add(lib.OAuthStateDurationMins * time.Minute),
		UserID:    id,
	}

	if err := db.Create(oauthState).Error; err != nil {
		return nil, err
	}

	return oauthState, nil
}

// checks states' expiresAt and if they expired, it Deletes them
func (db *DB) DeleteExpiredOAuthStates() {
	db.Where("expires_at < ?", time.Now()).Delete(&types.OAuthState{})
}

// Deletes a given oauth state from the database
func (db *DB) DeleteOAuthState(id uuid.UUID) error {
	var state = types.OAuthState{
		UUID_ID: types.UUID_ID{ID: id},
	}
	result := db.Delete(&state)
	return result.Error
}