import { readFileSync } from 'node:fs';
import { programCsAzureMonitorMigration } from '../src/migrations/program-cs-azure-monitor-migration.js';

const migration = programCsAzureMonitorMigration.migrations[0];

function runFixture(label: string, content: string) {
  console.log(`\n${'='.repeat(70)}`);
  console.log(`Fixture: ${label}`);
  console.log('='.repeat(70));
  const detected = migration.detect(content, '');
  console.log(`detect() → ${detected}`);
  if (!detected) {
    console.log('(no transformation)');
    return content;
  }
  const out = migration.transform(content, '');
  const lines = out.split('\n');
  console.log('--- USINGS (first 12 lines) ---');
  console.log(lines.slice(0, 12).join('\n'));
  console.log('--- AROUND AddSmartStack ---');
  const idxAdd = lines.findIndex((l) => l.includes('builder.Services.AddSmartStack('));
  console.log(lines.slice(Math.max(0, idxAdd - 8), idxAdd + 5).join('\n'));
  console.log('--- AROUND UseSmartStack ---');
  const idxUse = lines.findIndex((l) => l.includes('app.UseSmartStack('));
  console.log(lines.slice(idxUse, idxUse + 6).join('\n'));
  return out;
}

const polluted = readFileSync('D:/_test/cli/Gesa/src/Gesa.Api/Program.cs', 'utf-8');
const pollutedOut = runFixture('Polluted Program.cs (Claude Code AddHangfire injection)', polluted);

const pristine = `using Serilog;
using Serilog.Events;
using Microsoft.EntityFrameworkCore;
using SmartStack.Api.Extensions;
using MyApp.Infrastructure;
using MyApp.Infrastructure.Persistence;
using MyApp.Application;

try
{
    var builder = WebApplication.CreateBuilder(args);

    builder.Host.UseSmartStackSerilog();

    // Application Insights SDK (must be added before Serilog runs)
    var aiConnectionString = builder.Configuration["Logging:Sinks:ApplicationInsights:ConnectionString"];
    var aiEnabled = builder.Configuration.GetValue<bool>("Logging:Sinks:ApplicationInsights:Enabled");
    if (!string.IsNullOrEmpty(aiConnectionString) && aiEnabled)
    {
        builder.Services.AddApplicationInsightsTelemetry(options =>
        {
            options.ConnectionString = aiConnectionString;
        });
    }

    // ===================================================================
    // 1. Add SmartStack Core services (from NuGet package)
    // ===================================================================
    builder.Services.AddSmartStack(builder.Configuration, options =>
    {
        options.EnableDevSeeding = builder.Environment.IsDevelopment();
    });

    var app = builder.Build();
    await app.InitializeSmartStackAsync();
    app.UseSmartStackSwagger();
    app.UseSmartStack();
    app.MapSmartStack();
    app.Run();
}
catch (Exception ex)
{
    Log.Fatal(ex, "Application terminated unexpectedly");
}
`;
runFixture('Pristine old Program.cs (v4 generation)', pristine);

console.log(`\n${'='.repeat(70)}`);
console.log('Idempotency check (transform twice = transform once?)');
console.log('='.repeat(70));
const once = migration.transform(polluted, '');
const twice = migration.transform(once, '');
console.log(`once === twice : ${once === twice}`);
if (once !== twice) {
  console.log('--- DIFF ---');
  const linesOnce = once.split('\n');
  const linesTwice = twice.split('\n');
  for (let i = 0; i < Math.max(linesOnce.length, linesTwice.length); i++) {
    if (linesOnce[i] !== linesTwice[i]) {
      console.log(`L${i}: once=${JSON.stringify(linesOnce[i])} twice=${JSON.stringify(linesTwice[i])}`);
    }
  }
}