package integration

import (
	"errors"
	"rideaware/pkg/database"
	"time"

	"gorm.io/gorm"
)

type Repository struct{}

func NewRepository() *Repository {
	return &Repository{}
}

// UpsertConnection creates or updates an OAuth connection for a user+provider pair.
func (r *Repository) UpsertConnection(conn *OAuthConnection) error {
	var existing OAuthConnection
	err := database.DB.Where("user_id = ? AND provider = ?", conn.UserID, conn.Provider).
		First(&existing).Error

	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return database.DB.Create(conn).Error
		}
		return err
	}

	existing.AccessToken = conn.AccessToken
	existing.RefreshToken = conn.RefreshToken
	existing.TokenExpiresAt = conn.TokenExpiresAt
	existing.ProviderUserID = conn.ProviderUserID
	existing.Scopes = conn.Scopes
	existing.Status = "active"

	conn.ID = existing.ID
	return database.DB.Save(&existing).Error
}

// GetConnection retrieves an active OAuth connection for a user+provider pair.
func (r *Repository) GetConnection(userID uint, provider string) (*OAuthConnection, error) {
	var conn OAuthConnection
	if err := database.DB.Where("user_id = ? AND provider = ?", userID, provider).
		First(&conn).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, errors.New("no " + provider + " connection found")
		}
		return nil, err
	}
	return &conn, nil
}

// UpdateConnection updates an existing OAuth connection.
func (r *Repository) UpdateConnection(conn *OAuthConnection) error {
	return database.DB.Save(conn).Error
}

// DeleteConnection removes an OAuth connection.
func (r *Repository) DeleteConnection(userID uint, provider string) error {
	return database.DB.Where("user_id = ? AND provider = ?", userID, provider).
		Delete(&OAuthConnection{}).Error
}

// CreateState stores an OAuth state token for CSRF protection.
func (r *Repository) CreateState(state *OAuthState) error {
	return database.DB.Create(state).Error
}

// GetAndDeleteState retrieves and deletes an OAuth state token. Returns error if expired or not found.
func (r *Repository) GetAndDeleteState(stateToken string) (*OAuthState, error) {
	var state OAuthState
	if err := database.DB.Where("state = ?", stateToken).First(&state).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, errors.New("invalid or expired state token")
		}
		return nil, err
	}

	// Delete the state immediately (single-use)
	database.DB.Delete(&state)

	if time.Now().After(state.ExpiresAt) {
		return nil, errors.New("state token has expired")
	}

	return &state, nil
}

// CleanupExpiredStates removes expired OAuth state tokens.
func (r *Repository) CleanupExpiredStates() error {
	return database.DB.Where("expires_at < ?", time.Now()).Delete(&OAuthState{}).Error
}