package mock

import (
	"context"
	"encoding/json"
	"io"
	"net/http"
	"strings"

	"golang.org/x/oauth2"

	"base/internal/pkg/oauth/types"
)

type client struct {
	oauthConfig *oauth2.Config
	userinfoURL string
}

// New creates a mock OAuth client that uses a local mock OAuth server.
// Use for local development when real Google/GitHub credentials are not available.
func New(config oauth2.Config, baseURL string) types.Oauth {
	baseURL = strings.TrimSuffix(baseURL, "/")
	oauthConfig := &oauth2.Config{
		ClientID:     config.ClientID,
		ClientSecret: config.ClientSecret,
		RedirectURL:  config.RedirectURL,
		Scopes:       config.Scopes,
		Endpoint: oauth2.Endpoint{
			AuthURL:  baseURL + "/authorize",
			TokenURL: baseURL + "/token",
		},
	}
	return &client{
		oauthConfig: oauthConfig,
		userinfoURL: baseURL + "/userinfo",
	}
}

func (c *client) GetConsentAuthUrl(ctx context.Context, state string) string {
	return c.oauthConfig.AuthCodeURL(state, oauth2.AccessTypeOffline)
}

func (c *client) ExchangeCodeWithToken(ctx context.Context, code string) (*types.Token, error) {
	exchange, err := c.oauthConfig.Exchange(ctx, code, oauth2.AccessTypeOffline)
	if err != nil {
		return nil, err
	}
	token, err := c.oauthConfig.TokenSource(ctx, exchange).Token()
	if err != nil {
		return nil, err
	}
	return &types.Token{
		AccessToken:  token.AccessToken,
		TokenType:    token.TokenType,
		RefreshToken: token.RefreshToken,
		ExpiresIn:    token.ExpiresIn,
	}, nil
}

func (c *client) GetUserInfo(ctx context.Context, accessToken, _ string) (types.UserInfo, error) {
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, c.userinfoURL, nil)
	if err != nil {
		return nil, err
	}
	req.Header.Set("Authorization", "Bearer "+accessToken)
	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	data, err := io.ReadAll(resp.Body)
	if err != nil {
		return nil, err
	}
	var user UserInfo
	if err := json.Unmarshal(data, &user); err != nil {
		return nil, err
	}
	return &user, nil
}