package service

import (
	"context"
	"fmt"
	"os"
	"slices"

	"gitlab.com/tensorsecurity-rd/waf-console/internal/model"
	"gitlab.com/tensorsecurity-rd/waf-console/pkg/apis/waf.security.io/v1alpha1"
	"gitlab.com/tensorsecurity-rd/waf-console/pkg/generated/clientset/versioned"
	"gopkg.in/yaml.v3"
	"gorm.io/gorm"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
)

type wafService struct {
	client *versioned.Clientset
	db     *gorm.DB
}

func NewWafService(client *versioned.Clientset, db *gorm.DB) Service {
	return &wafService{client: client, db: db}
}

func (s *wafService) GetWaf(ctx context.Context, regionCode, namespace, gatewayName string) (*WafService, error) {
	wafService := &model.WafService{}
	err := s.db.Model(&model.WafService{}).Where("gateway_name = ? AND region_code = ? AND namespace = ?", gatewayName, regionCode, namespace).First(wafService).Error
	if err != nil {
		if err == gorm.ErrRecordNotFound {
			// Create new WAF service record if not found
			wafService = &model.WafService{
				RegionCode:  regionCode,
				Namespace:   namespace,
				GatewayName: gatewayName,
				Mode:        string(WafModeAlert),
			}
			if err := s.db.Create(wafService).Error; err != nil {
				return nil, fmt.Errorf("failed to create WAF service: %v", err)
			}
		} else {
			return nil, fmt.Errorf("failed to query WAF service: %v", err)
		}
	}
	return &WafService{
		GatewayName: wafService.GatewayName,
		Mode:        wafService.Mode,
		RuleNum:     wafService.RuleNum,
		AttackNum:   wafService.AttackNum,
	}, nil
}

func (s *wafService) CreateWaf(ctx context.Context, req *CreateWafReq) (*WafService, error) {
	// Create the WAF service resource
	service := &v1alpha1.Service{
		ObjectMeta: metav1.ObjectMeta{
			Name:      req.GatewayName,
			Namespace: req.Namespace,
		},
		Spec: v1alpha1.ServiceSpec{
			HostNames:   req.Host,
			ServiceName: req.GatewayName,
			Port:        req.Port,
			Workload: v1alpha1.WorkloadRef{
				Kind:      "Deployment",
				Name:      req.GatewayName,
				Namespace: req.Namespace,
			},
			Uri: &v1alpha1.StringMatch{
				Prefix: "/",
			},
			LogConfig: &v1alpha1.LogConfig{
				Enable: 1,
				Level:  "info",
			},
			Mode: "block",
		},
	}

	// Get enabled rule categories from DB
	var ruleCategories []model.WafRuleCategory
	if err := s.db.Model(&model.WafRuleCategory{}).Where("status = ?", 0).Find(&ruleCategories).Error; err != nil {
		return nil, fmt.Errorf("failed to get rule categories: %v", err)
	}

	// Get existing WAF service config if any
	wafService := &model.WafService{}
	err := s.db.Model(&model.WafService{}).Where("gateway_name = ?", req.GatewayName).First(wafService).Error
	if err != nil {
		if err == gorm.ErrRecordNotFound {
			// Create new WAF service record if not found
			wafService = &model.WafService{
				RegionCode:  req.RegionCode,
				Namespace:   req.Namespace,
				GatewayName: req.GatewayName,
				Mode:        string(WafModeAlert),
			}
			if err := s.db.Create(wafService).Error; err != nil {
				return nil, fmt.Errorf("failed to create WAF service: %v", err)
			}
		} else {
			return nil, fmt.Errorf("failed to query WAF service: %v", err)
		}
	}

	// Determine which rule categories to enable
	var enabledCategories []model.WafRuleCategory

	if wafService.RuleCategoryStatus != nil && len(wafService.RuleCategoryStatus.CategoryID) > 0 {
		// Only include categories not already enabled
		for _, category := range ruleCategories {
			if !slices.Contains(wafService.RuleCategoryStatus.CategoryID, category.CategoryID) {
				enabledCategories = append(enabledCategories, category)
			}
		}
	} else {
		// Enable all categories if none specified
		enabledCategories = ruleCategories
	}

	// Add rules from enabled categories
	for _, category := range enabledCategories {
		for _, rule := range category.Rules {
			service.Spec.Rules = append(service.Spec.Rules, v1alpha1.Rule{
				ID:          rule.ID,
				Level:       rule.Level,
				Name:        rule.Name,
				Type:        rule.Type,
				Description: rule.Description,
				Expr:        rule.Expr,
				Mode:        rule.Mode,
			})
		}
	}

	// Create the WAF service in Kubernetes
	if _, err := s.client.WafV1alpha1().Services(req.Namespace).Create(ctx, service, metav1.CreateOptions{}); err != nil {
		return nil, fmt.Errorf("failed to create WAF service: %v", err)
	}

	return nil, nil
}

func (s *wafService) UpdateMode(ctx context.Context, req *UpdateModeReq) (*WafService, error) {
	// Check if WAF service exists
	wafService := &model.WafService{}
	err := s.db.Model(&model.WafService{}).Where("gateway_name = ?", req.GatewayName).First(wafService).Error
	if err != nil {
		if err == gorm.ErrRecordNotFound {
			// Create new WAF service record if not found
			wafService = &model.WafService{
				RegionCode:  req.RegionCode,
				Namespace:   req.Namespace,
				GatewayName: req.GatewayName,
				Mode:        string(req.Mode),
			}
			if err := s.db.Create(wafService).Error; err != nil {
				return nil, fmt.Errorf("failed to create WAF service: %v", err)
			}
		} else {
			return nil, fmt.Errorf("failed to query WAF service: %v", err)
		}
	} else {
		// Update mode if service exists
		if err := s.db.Model(wafService).Update("mode", string(req.Mode)).Error; err != nil {
			return nil, fmt.Errorf("failed to update WAF service mode: %v", err)
		}
	}
	return nil, nil
}

func (s *wafService) GetRuleCategories(ctx context.Context) ([]WafRuleCategory, error) {
	var categories []WafRuleCategory
	err := s.db.Table("waf_rule_categories").Find(&categories).Error
	if err != nil {
		return nil, err
	}
	return categories, nil
}

func (s *wafService) GetRules(ctx context.Context, categoryID string) ([]WafRule, error) {
	var rules []WafRule
	err := s.db.Table("waf_rules").Where("category_id = ?", categoryID).Find(&rules).Error
	if err != nil {
		return nil, err
	}
	return rules, nil
}

func (s *wafService) GetRule(ctx context.Context, ruleID int) (*WafRule, error) {
	var rule WafRule
	err := s.db.Table("waf_rules").Where("id = ?", ruleID).First(&rule).Error
	if err != nil {
		return nil, err
	}
	return &rule, nil
}

func (s *wafService) SaveRuleCategoryToDB(ctx context.Context) error {
	var categories []WafRuleCategory
	yamlFile, err := os.ReadFile("rules/waf-rules.yaml")
	if err != nil {
		return fmt.Errorf("error reading yaml file: %v", err)
	}

	err = yaml.Unmarshal(yamlFile, &categories)
	if err != nil {
		return fmt.Errorf("error unmarshaling yaml: %v", err)
	}

	for _, category := range categories {
		rules := []model.WafRule{}
		for _, rule := range category.Rules {
			rules = append(rules, model.WafRule{
				ID:          rule.ID,
				CategoryID:  category.CategoryID,
				Level:       rule.Level,
				Name:        rule.Name,
				Type:        rule.Type,
				Description: rule.Description,
				Expr:        rule.Expr,
				Mode:        rule.Mode,
			})
		}
		model := model.WafRuleCategory{
			CategoryID:    category.CategoryID,
			Status:        category.Status,
			CategoryEN:    category.Catagory.EN,
			CategoryZH:    category.Catagory.Zh,
			DescriptionEN: category.Description.EN,
			DescriptionZH: category.Description.Zh,
			Rules:         model.RuleList(rules),
		}
		err = s.db.Table("waf_rule_categories").Create(&model).Error
		if err != nil {
			return err
		}
	}

	return nil
}
