using Microsoft.Extensions.Configuration;
using PrismaticSync.Infrastructure;
using PrismaticSync.Services;

// ── Load config ───────────────────────────────────────────────────────────────
var configRoot = new ConfigurationBuilder()
    .SetBasePath(AppContext.BaseDirectory)
    .AddJsonFile("appsettings.json", optional: false)
    .Build();

var config = configRoot.GetSection("Sync").Get<SyncConfig>() ?? new SyncConfig();
Log.Configure(config.LogFile);

// ── Parse args ────────────────────────────────────────────────────────────────
var command = args.Length > 0 && !args[0].StartsWith("--") ? args[0].ToLowerInvariant() : "run";
var headed = args.Contains("--headed");
var retryErrors = args.Contains("--retry-errors");
var maxProducts = GetIntArg("--max-products", 0);
// "run" refreshes products older than 30 days by default; explicit commands default to new-only.
var refreshOlderThanDays = GetIntArg("--refresh-older-than", command == "run" ? 30 : 0);

Log.Info($"PrismaticSync — command '{command}' (headed={headed}, refreshOlderThan={refreshOlderThanDays}d, maxProducts={maxProducts})");

try
{
    switch (command)
    {
        case "discover-new":
            await WithBrowser(d => new PrismaticDiscoverer(d, config).DiscoverNewAsync());
            break;

        case "discover-full":
            await WithBrowser(d => new PrismaticDiscoverer(d, config).DiscoverFullAsync());
            break;

        case "scrape":
            await WithBrowser(d => new PrismaticScraper(d, config).ScrapeAsync(refreshOlderThanDays, maxProducts, retryErrors));
            break;

        case "push":
            await new CatalogPusher(config).PushAsync();
            break;

        case "run":
            // The scheduled default: find new colors, scrape new + stale, then push.
            await WithBrowser(async d =>
            {
                await new PrismaticDiscoverer(d, config).DiscoverNewAsync();
                await new PrismaticScraper(d, config).ScrapeAsync(refreshOlderThanDays, maxProducts, retryErrors);
            });
            await new CatalogPusher(config).PushAsync();
            break;

        default:
            PrintUsage();
            return 1;
    }

    Log.Info("Done.");
    return 0;
}
catch (Exception ex)
{
    Log.Error($"Fatal: {ex}");
    return 1;
}

// ── Helpers ───────────────────────────────────────────────────────────────────
async Task WithBrowser(Func<BrowserSession, Task> action)
{
    await using var session = await BrowserSession.CreateAsync(headed);
    await action(session);
}

int GetIntArg(string name, int fallback)
{
    var prefix = name + "=";
    var found = args.FirstOrDefault(a => a.StartsWith(prefix, StringComparison.OrdinalIgnoreCase));
    return found is not null && int.TryParse(found[prefix.Length..], out var value) ? value : fallback;
}

void PrintUsage()
{
    Console.WriteLine(
        """
        PrismaticSync — scrape Prismatic Powders and push to the app catalog.

        Usage: PrismaticSync [command] [options]

        Commands:
          run            (default) discover-new + scrape (new + stale) + push
          discover-new   Incremental discovery via newest-first sort (cheap; finds new colors)
          discover-full  Full discovery across all color filters (heavy; reconciles the whole set)
          scrape         Scrape product pages from the URL list (resumable)
          push           Push the scraped JSON to the import endpoint

        Options:
          --refresh-older-than=N   Re-scrape products whose data is older than N days (default 30 for 'run')
          --max-products=N         Cap products scraped this run (0 = no cap)
          --retry-errors           Retry URLs previously recorded as errors
          --headed                 Show the browser window (debugging)

        Config: appsettings.json (delays, file paths, import endpoint + token).
        First run on a new machine: dotnet build, then `pwsh bin/Debug/net8.0/playwright.ps1 install chromium`.
        """);
}