package service

import (
	"context"
	"strconv"
	"sync"
	"time"

	"kra/internal/biz"
	"kra/internal/conf"
)

type SecurityService struct {
	uc            *biz.SecurityUsecase
	runtime       *conf.Runtime
	securityMu    sync.RWMutex
	securityCache *biz.SecurityConfig
	cache         biz.Cache
	tokens        *biz.TokenUsecase
}

func NewSecurityService(uc *biz.SecurityUsecase, runtime *conf.Runtime, cache biz.Cache, tokens *biz.TokenUsecase) *SecurityService {
	return &SecurityService{uc: uc, runtime: runtime, cache: cache, tokens: tokens}
}

func (s *SecurityService) cacheGet(ctx context.Context, key string) (string, bool, error) {
	return s.cache.Get(ctx, key)
}

func (s *SecurityService) cacheSet(ctx context.Context, key, value string, expiration time.Duration) error {
	return s.cache.Set(ctx, key, value, expiration)
}

func (s *SecurityService) cacheDelete(ctx context.Context, key string) error {
	return s.cache.Delete(ctx, key)
}

func (s *SecurityService) cacheIncrement(ctx context.Context, key string, expiration time.Duration) (int64, error) {
	return s.cache.Increment(ctx, key, expiration)
}

func (s *SecurityService) ActiveToken(ctx context.Context, username string) (string, error) {
	value, _, err := s.cacheGet(ctx, activeTokenKey(username))
	return value, err
}

func (s *SecurityService) LoginLocked(ctx context.Context, username string) (bool, error) {
	_, locked, err := s.cacheGet(ctx, "login:lock:"+username)
	return locked, err
}

func (s *SecurityService) IncrementLoginFailure(ctx context.Context, username string, expiration time.Duration) (int64, error) {
	return s.cacheIncrement(ctx, "login:fail:"+username, expiration)
}

func (s *SecurityService) LockLogin(ctx context.Context, username string, expiration time.Duration) error {
	return s.cacheSet(ctx, "login:lock:"+username, "1", expiration)
}

func (s *SecurityService) ClearLoginState(ctx context.Context, username string) {
	_ = s.cacheDelete(ctx, "login:fail:"+username)
	_ = s.cacheDelete(ctx, "login:lock:"+username)
}

func (s *SecurityService) EnsureLoginIPCounter(ctx context.Context, ip string, expiration time.Duration) (int, error) {
	value, exists, err := s.cacheGet(ctx, ip)
	if err != nil {
		return 0, err
	}
	if exists {
		return strconv.Atoi(value)
	}
	if expiration <= 0 {
		expiration = time.Hour
	}
	if err = s.cacheSet(ctx, ip, "1", expiration); err != nil {
		return 0, err
	}
	return 1, nil
}

func (s *SecurityService) IncrementLoginIP(ctx context.Context, ip string, expiration time.Duration) (int64, error) {
	return s.cacheIncrement(ctx, ip, expiration)
}

func (s *SecurityService) IncrementRateLimit(ctx context.Context, key string, expiration time.Duration) (int64, error) {
	return s.cacheIncrement(ctx, key, expiration)
}

func (s *SecurityService) SetCaptcha(ctx context.Context, id, value string, expiration time.Duration) error {
	return s.cacheSet(ctx, "captcha:"+id, value, expiration)
}

func (s *SecurityService) GetCaptcha(ctx context.Context, id string) (string, bool, error) {
	return s.cacheGet(ctx, "captcha:"+id)
}

func (s *SecurityService) DeleteCaptcha(ctx context.Context, id string) error {
	return s.cacheDelete(ctx, "captcha:"+id)
}

func (s *SecurityService) UseMultipoint() bool {
	config := s.runtime.Admin()
	return config != nil && config.System != nil && config.System.UseMultipoint
}

func activeTokenKey(username string) string { return "jwt:active:" + username }

func (s *SecurityService) ActiveTokenMatches(ctx context.Context, username, token string) (bool, error) {
	if !s.UseMultipoint() {
		return true, nil
	}
	active, ok, err := s.cacheGet(ctx, activeTokenKey(username))
	return ok && active == token, err
}

func (s *SecurityService) RotateActiveToken(ctx context.Context, username, oldToken, newToken string, expiration time.Duration) error {
	if !s.UseMultipoint() {
		return nil
	}
	if oldToken != "" && oldToken != newToken {
		if err := s.tokens.BlacklistToken(ctx, oldToken); err != nil {
			return err
		}
	}
	return s.cacheSet(ctx, activeTokenKey(username), newToken, expiration)
}