package application

import (
	"context"
	"crypto/rand"
	"encoding/base64"
	"errors"
	"io"
	"time"

	"git.coopgo.io/coopgo-platform/groups-management/grpcapi"
	mobilityaccounts "git.coopgo.io/coopgo-platform/mobility-accounts/grpcapi"
	ma "git.coopgo.io/coopgo-platform/mobility-accounts/storage"
	groupsstorage "git.coopgo.io/coopgo-platform/groups-management/storage"
	"github.com/coreos/go-oidc/v3/oidc"
	"github.com/rs/zerolog/log"
)

type OAuth2CallbackResult struct {
	RedirectURL string
	IDToken     string
}

func (h *ApplicationHandler) ProcessOAuth2Callback(code string, redirectSession string) (*OAuth2CallbackResult, error) {
	oauth2Token, err := h.idp.OAuth2Config.Exchange(context.Background(), code)
	if err != nil {
		log.Error().Err(err).Msg("Exchange error")
		return nil, err
	}

	// Extract the ID Token from OAuth2 token.
	rawIDToken, ok := oauth2Token.Extra("id_token").(string)
	if !ok {
		log.Error().Msg("Cannot retrieve ID token")
		return nil, errors.New("cannot retrieve ID token")
	}

	_, err = h.idp.TokenVerifier.Verify(context.Background(), rawIDToken)
	if err != nil {
		log.Error().Err(err).Msg("Not able to verify token")
		return nil, err
	}

	redirect := "/app/"
	if redirectSession != "" {
		redirect = redirectSession
	}

	return &OAuth2CallbackResult{
		RedirectURL: redirect,
		IDToken:     rawIDToken,
	}, nil
}

type LostPasswordInitResult struct {
	Success bool
}

func (h *ApplicationHandler) InitiateLostPassword(email string) (*LostPasswordInitResult, error) {
	account, err := h.services.GRPC.MobilityAccounts.GetAccountUsername(context.TODO(), &mobilityaccounts.GetAccountUsernameRequest{
		Username:  email,
		Namespace: "parcoursmob",
	})
	if err != nil {
		return nil, err
	}

	b := make([]byte, 16)
	if _, err := io.ReadFull(rand.Reader, b); err != nil {
		return nil, err
	}
	key := base64.RawURLEncoding.EncodeToString(b)

	passwordretrieval := map[string]any{
		"username":   email,
		"account_id": account.Account.Id,
		"key":        key,
	}

	h.cache.PutWithTTL("retrieve-password/"+key, passwordretrieval, 72*time.Hour)

	if err := h.emailing.Send("auth.retrieve_password", email, passwordretrieval); err != nil {
		return nil, err
	}

	return &LostPasswordInitResult{Success: true}, nil
}

type LostPasswordRecoverResult struct {
	Success bool
}

func (h *ApplicationHandler) RecoverLostPassword(key, newPassword string) (*LostPasswordRecoverResult, error) {
	recover, err := h.cache.Get("retrieve-password/" + key)
	if err != nil {
		return nil, err
	}

	if newPassword == "" {
		return nil, errors.New("password is empty")
	}

	_, err = h.services.GRPC.MobilityAccounts.ChangePassword(context.TODO(), &mobilityaccounts.ChangePasswordRequest{
		Id:       recover.(map[string]any)["account_id"].(string),
		Password: newPassword,
	})
	if err != nil {
		return nil, err
	}

	err = h.cache.Delete("retrieve-password/" + key)
	if err != nil {
		log.Error().Err(err).Msg("Failed to delete password recovery key")
	}

	return &LostPasswordRecoverResult{Success: true}, nil
}

func (h *ApplicationHandler) GetPasswordRecoveryData(key string) (map[string]any, error) {
	recover, err := h.cache.Get("retrieve-password/" + key)
	if err != nil {
		return nil, err
	}
	return recover.(map[string]any), nil
}

type OnboardingResult struct {
	Success bool
}

func (h *ApplicationHandler) CompleteOnboarding(key, password, firstName, lastName string) (*OnboardingResult, error) {
	onboarding, err := h.cache.Get("onboarding/" + key)
	if err != nil {
		return nil, err
	}

	onboardingmap := onboarding.(map[string]any)

	if password == "" {
		return nil, errors.New("password is empty")
	}

	groups := []string{
		onboardingmap["group"].(string),
	}

	if onboardingmap["admin"].(bool) {
		groups = append(groups, onboardingmap["group"].(string)+":admin")
	}

	display_name := firstName + " " + lastName
	account := &ma.Account{
		Authentication: ma.AccountAuth{
			Local: ma.LocalAuth{
				Username: onboardingmap["username"].(string),
				Password: password,
			},
		},
		Namespace: "parcoursmob",
		Data: map[string]any{
			"display_name": display_name,
			"first_name":   firstName,
			"last_name":    lastName,
			"email":        onboardingmap["username"],
			"groups":       groups,
		},
	}

	acc, err := mobilityaccounts.AccountFromStorageType(account)
	if err != nil {
		return nil, err
	}

	request := &mobilityaccounts.RegisterRequest{
		Account: acc,
	}

	_, err = h.services.GRPC.MobilityAccounts.Register(context.TODO(), request)
	if err != nil {
		return nil, err
	}

	err = h.cache.Delete("onboarding/" + key)
	if err != nil {
		log.Error().Err(err).Msg("Failed to delete onboarding key")
	}

	return &OnboardingResult{Success: true}, nil
}

func (h *ApplicationHandler) GetOnboardingData(key string) (map[string]any, error) {
	onboarding, err := h.cache.Get("onboarding/" + key)
	if err != nil {
		return nil, err
	}
	return onboarding.(map[string]any), nil
}

type UserGroupsResult struct {
	Groups []groupsstorage.Group
}

func (h *ApplicationHandler) GetUserGroups(idtoken *oidc.IDToken) (*UserGroupsResult, error) {
	var claims map[string]any
	err := idtoken.Claims(&claims)
	if err != nil {
		return nil, err
	}

	g := claims["groups"]
	groups_interface, ok := g.([]any)
	if !ok {
		return nil, errors.New("invalid groups format")
	}

	groups := []string{}
	for _, v := range groups_interface {
		groups = append(groups, v.(string))
	}

	request := &grpcapi.GetGroupsBatchRequest{
		Groupids: groups,
	}

	resp, err := h.services.GRPC.GroupsManagement.GetGroupsBatch(context.TODO(), request)
	if err != nil {
		return nil, err
	}

	var groupsresponse []groupsstorage.Group
	for _, group := range resp.Groups {
		if group.Namespace != "parcoursmob_organizations" {
			continue
		}
		g := group.ToStorageType()
		groupsresponse = append(groupsresponse, g)
	}

	return &UserGroupsResult{Groups: groupsresponse}, nil
}