package auth

import (
	"context"
	"strings"

	"gateway/internal/library/zitadel"
	domauth "gateway/internal/model/auth/domain/usecase"
	memberdom "gateway/internal/model/member/domain"
	dommember "gateway/internal/model/member/domain/usecase"
	"gateway/internal/svc"
	"gateway/internal/types"

	"github.com/zeromicro/go-zero/core/logx"
)

type RegisterSocialCallbackLogic struct {
	logx.Logger
	ctx    context.Context
	svcCtx *svc.ServiceContext
}

func NewRegisterSocialCallbackLogic(ctx context.Context, svcCtx *svc.ServiceContext) *RegisterSocialCallbackLogic {
	return &RegisterSocialCallbackLogic{
		Logger: logx.WithContext(ctx),
		ctx:    ctx,
		svcCtx: svcCtx,
	}
}

func (l *RegisterSocialCallbackLogic) RegisterSocialCallback(req *types.RegisterSocialCallbackReq) (*types.AuthTokenData, error) {
	if l.svcCtx.Zitadel == nil || l.svcCtx.AuthRegistrationSession == nil {
		return nil, errb.SysNotImplemented("social registration not configured")
	}
	if l.svcCtx.MemberProvisioning == nil || l.svcCtx.MemberProfile == nil {
		return nil, errb.SysNotImplemented("member provisioning not configured")
	}
	if l.svcCtx.AuthToken == nil {
		return nil, errb.SysNotImplemented("auth token not configured")
	}

	sessionID, err := parseRegisterOAuthState(req.State)
	if err != nil {
		return nil, err
	}

	session, err := l.svcCtx.AuthRegistrationSession.Get(l.ctx, sessionID)
	if err != nil {
		return nil, err
	}
	defer func() {
		if delErr := l.svcCtx.AuthRegistrationSession.Delete(l.ctx, sessionID); delErr != nil {
			logx.WithContext(l.ctx).Errorf("register social callback: delete session: %v", delErr)
		}
	}()

	tok, err := l.svcCtx.Zitadel.ExchangeAuthorizationCode(l.ctx, req.Code, session.RedirectURI)
	if err != nil {
		return nil, wrapZitadelErr(err)
	}
	var claims *zitadel.IDTokenClaims
	if tok.IDToken != "" {
		claims, err = l.svcCtx.Zitadel.VerifyIDToken(l.ctx, tok.IDToken)
	} else {
		claims, err = zitadelIdentityFromToken(l.ctx, l.svcCtx.Zitadel, tok)
	}
	if err != nil {
		return nil, wrapZitadelErr(err)
	}

	trustSocial := l.svcCtx.Config.Member.Defaults().Registration.TrustSocialEmailVerified
	if err := federatedEmailAllowed(claims, session.Provider, trustSocial); err != nil {
		return nil, err
	}

	isExisting := false
	if _, err := l.svcCtx.MemberProfile.GetByZitadelUserID(l.ctx, session.TenantID, claims.Sub); err == nil {
		isExisting = true
	} else if !isMemberNotFound(err) {
		return nil, err
	}
	if isExisting && session.InviteNewUsersOnly {
		return nil, errb.ResAlreadyExist("account already exists, please login").WithCause(memberdom.ErrDuplicateMember)
	}

	var inviteCodeID string
	if l.svcCtx.Config.Member.Defaults().Registration.RequireInviteCode {
		if l.svcCtx.AuthInvite == nil {
			return nil, errb.SysNotImplemented("invite validation not configured")
		}
		consumed, err := l.svcCtx.AuthInvite.Consume(l.ctx, &domauth.ConsumeInviteRequest{
			TenantID: session.TenantID,
			Code:     session.InviteCode,
		})
		if err != nil {
			return nil, err
		}
		inviteCodeID = consumed.ID
	}

	provider := strings.ToLower(strings.TrimSpace(session.Provider))
	var memberDTO *dommember.MemberDTO
	switch provider {
	case "ldap":
		memberDTO, err = l.svcCtx.MemberProvisioning.EnsureFromLDAP(l.ctx, &dommember.EnsureFromLDAPRequest{
			TenantID:    session.TenantID,
			ZitadelSub:  claims.Sub,
			ExternalID:  claims.Sub,
			Email:       claims.Email,
			DisplayName: claims.Name,
		})
	default:
		memberDTO, err = l.svcCtx.MemberProvisioning.EnsureFromOIDC(l.ctx, &dommember.EnsureFromOIDCRequest{
			TenantID:      session.TenantID,
			ZitadelSub:    claims.Sub,
			Email:         claims.Email,
			EmailVerified: claims.EmailVerified,
			DisplayName:   claims.Name,
			Locale:        firstNonEmpty(session.Language, claims.Locale),
		})
	}
	if err != nil {
		return nil, err
	}

	if !isExisting {
		if err := recordRegistrationMeta(l.ctx, l.svcCtx, session.TenantID, memberDTO.UID, inviteCodeID, session.AcceptTermsVersion, session.MarketingOptIn, registrationChannelForProvider(provider)); err != nil {
			return nil, err
		}
	}

	return issueAuthToken(l.ctx, l.svcCtx, session.TenantID, memberDTO.UID)
}

func firstNonEmpty(values ...string) string {
	for _, v := range values {
		if v != "" {
			return v
		}
	}
	return ""
}