using System;
using System.Collections.Generic;
using System.IO;
using System.Text;

namespace IdleSpectator;

public sealed class CatalogCoverageDiff
{
    public string Domain = "";
    public int LiveTotal;
    public int AuthoredTotal;
    public int Missing;
    public int Orphan;
    public readonly List<string> MissingIds = new List<string>();
    public readonly List<string> OrphanIds = new List<string>();

    public bool Passed => Missing == 0 && Orphan == 0;

    public string Detail =>
        $"{Domain}: live={LiveTotal} authored={AuthoredTotal} missing={Missing} orphan={Orphan}";
}

/// <summary>Shared live-vs-authored coverage audit used by domain event catalogs.</summary>
public static class CatalogCoverageAudit
{
    public static CatalogCoverageDiff Diff(
        string domain,
        IEnumerable<string> liveIds,
        IEnumerable<string> authoredIds)
    {
        var live = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        var authored = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        var diff = new CatalogCoverageDiff { Domain = domain ?? "domain" };

        if (liveIds != null)
        {
            foreach (string id in liveIds)
            {
                if (string.IsNullOrEmpty(id))
                {
                    continue;
                }

                live.Add(id.Trim());
            }
        }

        if (authoredIds != null)
        {
            foreach (string id in authoredIds)
            {
                if (string.IsNullOrEmpty(id))
                {
                    continue;
                }

                authored.Add(id.Trim());
            }
        }

        diff.LiveTotal = live.Count;
        diff.AuthoredTotal = authored.Count;

        foreach (string id in live)
        {
            if (!authored.Contains(id))
            {
                diff.Missing++;
                diff.MissingIds.Add(id);
            }
        }

        foreach (string id in authored)
        {
            if (!live.Contains(id))
            {
                diff.Orphan++;
                diff.OrphanIds.Add(id);
            }
        }

        return diff;
    }

    public static void WriteReport(string outputDirectory, string fileName, string body)
    {
        if (string.IsNullOrEmpty(outputDirectory) || string.IsNullOrEmpty(fileName))
        {
            return;
        }

        try
        {
            Directory.CreateDirectory(outputDirectory);
            File.WriteAllText(Path.Combine(outputDirectory, fileName), body ?? "");
        }
        catch
        {
            // ignore IO
        }
    }
}

public sealed class DomainEventAuditResult
{
    public bool Passed;
    public string Detail = "";
}

/// <summary>Coverage audits for relationship discrete events + live plot/era/book libraries.</summary>
public static class DomainEventHarness
{
    public static DomainEventAuditResult RunAudit(string outputDirectory)
    {
        var tsv = new StringBuilder();
        tsv.AppendLine("domain\tid\tauthored\towns_camera\tevent_strength\tnotes");

        CatalogCoverageDiff plots = CatalogCoverageAudit.Diff(
            "plots",
            ActivityAssetCatalog.EnumerateLivePlotIds(),
            PlotInterestCatalog.AuthoredIds);
        AppendLibraryDomain(tsv, "plots", ActivityAssetCatalog.EnumerateLivePlotIds(), plots, PlotInterestCatalog.GetOrFallback);

        CatalogCoverageDiff eras = CatalogCoverageAudit.Diff(
            "eras",
            ActivityAssetCatalog.EnumerateLiveEraIds(),
            EraInterestCatalog.AuthoredIds);
        AppendLibraryDomain(tsv, "eras", ActivityAssetCatalog.EnumerateLiveEraIds(), eras, EraInterestCatalog.GetOrFallback);

        CatalogCoverageDiff books = CatalogCoverageAudit.Diff(
            "books",
            ActivityAssetCatalog.EnumerateLiveBookTypeIds(),
            BookInterestCatalog.AuthoredIds);
        AppendLibraryDomain(tsv, "books", ActivityAssetCatalog.EnumerateLiveBookTypeIds(), books, BookInterestCatalog.GetOrFallback);

        CatalogCoverageDiff traits = CatalogCoverageAudit.Diff(
            "traits",
            ActivityAssetCatalog.EnumerateLiveTraitIds(),
            TraitInterestCatalog.AuthoredIds);
        AppendLibraryDomain(tsv, "traits", ActivityAssetCatalog.EnumerateLiveTraitIds(), traits, TraitInterestCatalog.GetOrFallback);

        int relMissing = 0;
        int relTotal = 0;
        foreach (string id in RelationshipEventCatalog.AuthoredIds)
        {
            relTotal++;
            DiscreteEventEntry entry = RelationshipEventCatalog.GetOrFallback(id);
            bool ok = RelationshipEventCatalog.HasAuthored(id) && !entry.IsFallback;
            if (!ok)
            {
                relMissing++;
            }

            tsv.Append("relationship\t").Append(id).Append('\t')
                .Append(ok ? "1" : "0").Append('\t')
                .Append(entry.OwnsCamera).Append('\t')
                .Append(entry.EventStrength.ToString("0.#")).Append('\t')
                .Append(ok ? "ok" : "missing_authored").AppendLine();
        }

        CatalogCoverageAudit.WriteReport(outputDirectory, "domain_event_audit.tsv", tsv.ToString());

        bool passed = plots.Passed && eras.Passed && books.Passed && traits.Passed
                      && relMissing == 0 && relTotal > 0;
        string detail =
            $"{plots.Detail}; {eras.Detail}; {books.Detail}; {traits.Detail}; relationship: authored={relTotal} missing={relMissing}";
        return new DomainEventAuditResult { Passed = passed, Detail = detail };
    }

    private static void AppendLibraryDomain(
        StringBuilder tsv,
        string domain,
        IEnumerable<string> liveIds,
        CatalogCoverageDiff diff,
        Func<string, DiscreteEventEntry> lookup)
    {
        foreach (string id in liveIds)
        {
            DiscreteEventEntry entry = lookup(id);
            bool has = !entry.IsFallback;
            tsv.Append(domain).Append('\t').Append(id).Append('\t')
                .Append(has ? "1" : "0").Append('\t')
                .Append(entry.OwnsCamera).Append('\t')
                .Append(entry.EventStrength.ToString("0.#")).Append('\t')
                .Append(has ? "ok" : "missing_authored").AppendLine();
        }

        foreach (string id in diff.OrphanIds)
        {
            tsv.Append(domain).Append('\t').Append(id).Append("\t1\t\t0\torphan_authored").AppendLine();
        }
    }
}