// Package main implements the audit-verifier standalone verification tool
package main

import (
	"flag"
	"fmt"
	"log/slog"
	"os"
	"time"

	"github.com/jfraeys/fetch_ml/internal/audit"
	"github.com/jfraeys/fetch_ml/internal/logging"
)

func main() {
	var (
		logPath    string
		interval   time.Duration
		continuous bool
		verbose    bool
	)

	flag.StringVar(&logPath, "log-path", "", "Path to audit log file to verify (required)")
	flag.DurationVar(&interval, "interval", 15*time.Minute, "Verification interval for continuous mode")
	flag.BoolVar(&continuous, "continuous", false, "Run continuous verification in a loop")
	flag.BoolVar(&verbose, "verbose", false, "Enable verbose output")
	flag.Parse()

	if logPath == "" {
		fmt.Fprintln(os.Stderr, "Error: -log-path is required")
		flag.Usage()
		os.Exit(1)
	}

	// Setup logging
	logLevel := slog.LevelInfo
	if verbose {
		logLevel = slog.LevelDebug
	}
	logger := logging.NewLogger(logLevel, false)

	verifier := audit.NewChainVerifier(logger)

	if continuous {
		fmt.Printf("Starting continuous audit verification every %v...\n", interval)
		fmt.Printf("Press Ctrl+C to stop\n\n")

		// Run with alert function that prints to stdout
		verifier.ContinuousVerification(logPath, interval, func(result *audit.VerificationResult) {
			printResult(result)
			if !result.Valid {
				// In continuous mode, we don't exit on tampering - we keep monitoring
				// The alert function should notify appropriate channels (email, slack, etc.)
				fmt.Println("\n*** TAMPERING DETECTED - INVESTIGATE IMMEDIATELY ***")
			}
		})
	} else {
		// Single verification run
		fmt.Printf("Verifying audit log: %s\n", logPath)

		result, err := verifier.VerifyLogFile(logPath)
		if err != nil {
			fmt.Fprintf(os.Stderr, "Verification failed: %v\n", err)
			os.Exit(1)
		}

		printResult(result)

		if !result.Valid {
			fmt.Println("\n*** VERIFICATION FAILED - AUDIT CHAIN TAMPERING DETECTED ***")
			os.Exit(2)
		}

		fmt.Println("\n✓ Audit chain integrity verified")
	}
}

func printResult(result *audit.VerificationResult) {
	fmt.Printf("\nVerification Time: %s\n", result.Timestamp.Format(time.RFC3339))
	fmt.Printf("Total Events: %d\n", result.TotalEvents)
	fmt.Printf("Valid: %v\n", result.Valid)

	if result.ChainRootHash != "" {
		fmt.Printf("Chain Root Hash: %s...\n", result.ChainRootHash[:16])
	}

	if !result.Valid {
		if result.FirstTampered != -1 {
			fmt.Printf("First Tampered Event: %d\n", result.FirstTampered)
		}
		if result.Error != "" {
			fmt.Printf("Error: %s\n", result.Error)
		}
	}
}