package main

import (
	"fmt"
	"net"
	"strings"
)

// Domain/path restrictions describe HTTP probes only. An IP-only rule also
// matches conntrack initiators; a destination match never hides other clients.
type MonitoringRule struct {
	IP         string `json:"ip"`
	Domain     string `json:"domain,omitempty"`
	PathPrefix string `json:"pathPrefix,omitempty"`
}

func validateMonitoringRules(rules []MonitoringRule) ([]MonitoringRule, error) {
	if len(rules) > 32 {
		return nil, fmt.Errorf("Не более 32 правил мониторинга")
	}
	result := make([]MonitoringRule, 0, len(rules))
	for i, r := range rules {
		ip := net.ParseIP(strings.TrimSpace(r.IP))
		if ip == nil {
			return nil, fmt.Errorf("Правило %d: нужен точный IPv4/IPv6-адрес", i+1)
		}
		r.IP = ip.String()
		r.Domain = strings.ToLower(strings.TrimSpace(r.Domain))
		r.PathPrefix = strings.TrimSpace(r.PathPrefix)
		if len(r.Domain) > 253 || strings.ContainsAny(r.Domain, " /|\t\r\n") || len(r.PathPrefix) > 256 || strings.ContainsAny(r.PathPrefix, "|\r\n") || (r.PathPrefix != "" && !strings.HasPrefix(r.PathPrefix, "/")) {
			return nil, fmt.Errorf("Правило %d: проверьте домен и префикс пути (начинается с /)", i+1)
		}
		result = append(result, r)
	}
	return result, nil
}
func isMonitoringRequest(e TrafficEvent, rules []MonitoringRule) bool {
	if e.Kind != "request" {
		return false
	}
	for _, r := range rules {
		if e.IP == r.IP && (r.Domain == "" || strings.EqualFold(e.Domain, r.Domain)) && strings.HasPrefix(e.Path, r.PathPrefix) {
			return true
		}
	}
	return false
}
func isMonitoringFlow(f NetworkFlow, rules []MonitoringRule) bool {
	for _, r := range rules {
		if net.ParseIP(f.Source).Equal(net.ParseIP(r.IP)) && r.Domain == "" && r.PathPrefix == "" {
			return true
		}
	}
	return false
}
func monitoringSQL(rules []MonitoringRule) (string, []any) {
	var parts []string
	var args []any
	for _, r := range rules {
		p := "(ip=?"
		args = append(args, r.IP)
		if r.Domain != "" {
			p += " AND lower(domain)=?"
			args = append(args, r.Domain)
		}
		if r.PathPrefix != "" {
			p += " AND substr(path,1,length(?))=?"
			args = append(args, r.PathPrefix, r.PathPrefix)
		}
		parts = append(parts, p+")")
	}
	if len(parts) == 0 {
		return "", nil
	}
	return " AND NOT (kind='request' AND (" + strings.Join(parts, " OR ") + "))", args
}