package invite

import (
	"context"
	"errors"
	"strings"

	"gorm.io/gorm"
)

// GetLanding 返回邀请落地页信息，供被邀请用户查看邀请人及奖励。
func (s *InviteService) GetLanding(ctx context.Context, inviteCode string) (*LandingResponse, error) {
	inviteCode = strings.TrimSpace(inviteCode)
	if inviteCode == "" {
		return nil, NewAppError(400, "invalid_invite_code", "inviteCode is required")
	}
	mapping, err := s.findInviteCodeMappingByCode(ctx, inviteCode)
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, NewAppError(404, "invite_code_not_found", "invite code not found")
		}
		return nil, err
	}
	inviter, err := s.findUserBaseInfo(ctx, mapping.UserID)
	if err != nil {
		return nil, err
	}
	bundle, err := s.loadBundle(ctx, inviter.OriginSys)
	if err != nil {
		return nil, err
	}
	inviteeBindRule := firstRule(bundle.Rules, ruleTypeInviteeBind)
	return &LandingResponse{
		CampaignEnabled: bundle.Config.Enabled,
		SysOrigin:       inviter.OriginSys,
		InviterUserID:   inviter.ID,
		InviterNickname: inviter.UserNickname,
		InviterAvatar:   inviter.UserAvatar,
		InviteCode:      mapping.InviteCode,
		DownloadURL:     bundle.Config.DownloadURL,
		ShareTitle:      defaultIfBlank(bundle.Config.ShareTitle, defaultShareTitle),
		ShareDesc:       defaultIfBlank(bundle.Config.ShareDesc, defaultShareDesc),
		InviteeReward:   rewardFromRule(inviteeBindRule),
	}, nil
}