using System.Linq;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;
using MongoDB.Bson;
using StellaOps.Feedser.Models;
using StellaOps.Feedser.Source.Ghsa;
using StellaOps.Feedser.Source.Common;
using StellaOps.Feedser.Source.Ghsa.Internal;
using StellaOps.Feedser.Source.Osv.Internal;
using StellaOps.Feedser.Source.Osv;
using StellaOps.Feedser.Source.Nvd;
using StellaOps.Feedser.Storage.Mongo.Documents;
using StellaOps.Feedser.Storage.Mongo.Dtos;

var serializerOptions = new JsonSerializerOptions(JsonSerializerDefaults.Web)
{
    DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull,
};

var projectRoot = Path.GetFullPath(Path.Combine(AppContext.BaseDirectory, "..", "..", "..", "..", ".."));

var osvFixturesPath = Path.Combine(projectRoot, "src", "StellaOps.Feedser.Source.Osv.Tests", "Fixtures");
var ghsaFixturesPath = Path.Combine(projectRoot, "src", "StellaOps.Feedser.Source.Ghsa.Tests", "Fixtures");
var nvdFixturesPath = Path.Combine(projectRoot, "src", "StellaOps.Feedser.Source.Nvd.Tests", "Nvd", "Fixtures");

RewriteOsvFixtures(osvFixturesPath);
RewriteSnapshotFixtures(osvFixturesPath);
RewriteGhsaFixtures(osvFixturesPath);
RewriteCreditParityFixtures(ghsaFixturesPath, nvdFixturesPath);
return;

void RewriteOsvFixtures(string fixturesPath)
{
    var rawPath = Path.Combine(fixturesPath, "osv-ghsa.raw-osv.json");
    if (!File.Exists(rawPath))
    {
        Console.WriteLine($"[FixtureUpdater] OSV raw fixture missing: {rawPath}");
        return;
    }

    using var document = JsonDocument.Parse(File.ReadAllText(rawPath));
    var advisories = new List<Advisory>();
    foreach (var element in document.RootElement.EnumerateArray())
    {
        var dto = JsonSerializer.Deserialize<OsvVulnerabilityDto>(element.GetRawText(), serializerOptions);
        if (dto is null)
        {
            continue;
        }

        var ecosystem = dto.Affected?.FirstOrDefault()?.Package?.Ecosystem ?? "unknown";
        var uri = new Uri($"https://osv.dev/vulnerability/{dto.Id}");
        var documentRecord = new DocumentRecord(
            Guid.NewGuid(),
            OsvConnectorPlugin.SourceName,
            uri.ToString(),
            DateTimeOffset.UtcNow,
            "fixture-sha",
            DocumentStatuses.PendingMap,
            "application/json",
            null,
            new Dictionary<string, string>(StringComparer.Ordinal)
            {
                ["osv.ecosystem"] = ecosystem,
            },
            null,
            DateTimeOffset.UtcNow,
            null,
            null);

        var payload = BsonDocument.Parse(element.GetRawText());
        var dtoRecord = new DtoRecord(
            Guid.NewGuid(),
            documentRecord.Id,
            OsvConnectorPlugin.SourceName,
            "osv.v1",
            payload,
            DateTimeOffset.UtcNow);

        var advisory = OsvMapper.Map(dto, documentRecord, dtoRecord, ecosystem);
        advisories.Add(advisory);
    }

    advisories.Sort((left, right) => string.Compare(left.AdvisoryKey, right.AdvisoryKey, StringComparison.Ordinal));
    var snapshot = SnapshotSerializer.ToSnapshot(advisories);
    File.WriteAllText(Path.Combine(fixturesPath, "osv-ghsa.osv.json"), snapshot);
    Console.WriteLine($"[FixtureUpdater] Updated {Path.Combine(fixturesPath, "osv-ghsa.osv.json")}");
}

void RewriteSnapshotFixtures(string fixturesPath)
{
    var baselinePublished = new DateTimeOffset(2025, 1, 5, 12, 0, 0, TimeSpan.Zero);
    var baselineModified = new DateTimeOffset(2025, 1, 8, 6, 30, 0, TimeSpan.Zero);
    var baselineFetched = new DateTimeOffset(2025, 1, 8, 7, 0, 0, TimeSpan.Zero);

    var cases = new (string Ecosystem, string Purl, string PackageName, string SnapshotFile)[]
    {
        ("npm", "pkg:npm/%40scope%2Fleft-pad", "@scope/left-pad", "osv-npm.snapshot.json"),
        ("PyPI", "pkg:pypi/requests", "requests", "osv-pypi.snapshot.json"),
    };

    foreach (var (ecosystem, purl, packageName, snapshotFile) in cases)
    {
        var dto = new OsvVulnerabilityDto
        {
            Id = $"OSV-2025-{ecosystem}-0001",
            Summary = $"{ecosystem} package vulnerability",
            Details = $"Detailed description for {ecosystem} package {packageName}.",
            Published = baselinePublished,
            Modified = baselineModified,
            Aliases = new[] { $"CVE-2025-11{ecosystem.Length}", $"GHSA-{ecosystem.Length}abc-{ecosystem.Length}def-{ecosystem.Length}ghi" },
            Related = new[] { $"OSV-RELATED-{ecosystem}-42" },
            References = new[]
            {
                new OsvReferenceDto { Url = $"https://example.com/{ecosystem}/advisory", Type = "ADVISORY" },
                new OsvReferenceDto { Url = $"https://example.com/{ecosystem}/fix", Type = "FIX" },
            },
            Severity = new[]
            {
                new OsvSeverityDto { Type = "CVSS_V3", Score = "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H" },
            },
            Affected = new[]
            {
                new OsvAffectedPackageDto
                {
                    Package = new OsvPackageDto
                    {
                        Ecosystem = ecosystem,
                        Name = packageName,
                        Purl = purl,
                    },
                    Ranges = new[]
                    {
                        new OsvRangeDto
                        {
                            Type = "SEMVER",
                            Events = new[]
                            {
                                new OsvEventDto { Introduced = "0" },
                                new OsvEventDto { Fixed = "2.0.0" },
                            },
                        },
                    },
                    Versions = new[] { "1.0.0", "1.5.0" },
                    EcosystemSpecific = JsonDocument.Parse("{\"severity\":\"high\"}").RootElement.Clone(),
                },
            },
            DatabaseSpecific = JsonDocument.Parse("{\"source\":\"osv.dev\"}").RootElement.Clone(),
        };

        var document = new DocumentRecord(
            Guid.NewGuid(),
            OsvConnectorPlugin.SourceName,
            $"https://osv.dev/vulnerability/{dto.Id}",
            baselineFetched,
            "fixture-sha",
            DocumentStatuses.PendingParse,
            "application/json",
            null,
            new Dictionary<string, string>(StringComparer.Ordinal) { ["osv.ecosystem"] = ecosystem },
            null,
            baselineModified,
            null);

        var payload = BsonDocument.Parse(JsonSerializer.Serialize(dto, serializerOptions));
        var dtoRecord = new DtoRecord(Guid.NewGuid(), document.Id, OsvConnectorPlugin.SourceName, "osv.v1", payload, baselineModified);

        var advisory = OsvMapper.Map(dto, document, dtoRecord, ecosystem);
        var snapshot = SnapshotSerializer.ToSnapshot(advisory);
        File.WriteAllText(Path.Combine(fixturesPath, snapshotFile), snapshot);
        Console.WriteLine($"[FixtureUpdater] Updated {Path.Combine(fixturesPath, snapshotFile)}");
    }
}

void RewriteGhsaFixtures(string fixturesPath)
{
    var rawPath = Path.Combine(fixturesPath, "osv-ghsa.raw-ghsa.json");
    if (!File.Exists(rawPath))
    {
        Console.WriteLine($"[FixtureUpdater] GHSA raw fixture missing: {rawPath}");
        return;
    }

    JsonDocument document;
    try
    {
        document = JsonDocument.Parse(File.ReadAllText(rawPath));
    }
    catch (JsonException ex)
    {
        Console.WriteLine($"[FixtureUpdater] Failed to parse GHSA raw fixture '{rawPath}': {ex.Message}");
        return;
    }
    using (document)
    {
    var advisories = new List<Advisory>();
    foreach (var element in document.RootElement.EnumerateArray())
    {
        GhsaRecordDto dto;
        try
        {
            dto = GhsaRecordParser.Parse(Encoding.UTF8.GetBytes(element.GetRawText()));
        }
        catch (JsonException)
        {
            continue;
        }

        var uri = new Uri($"https://github.com/advisories/{dto.GhsaId}");
        var documentRecord = new DocumentRecord(
            Guid.NewGuid(),
            GhsaConnectorPlugin.SourceName,
            uri.ToString(),
            DateTimeOffset.UtcNow,
            "fixture-sha",
            DocumentStatuses.PendingMap,
            "application/json",
            null,
            new Dictionary<string, string>(StringComparer.Ordinal),
            null,
            DateTimeOffset.UtcNow,
            null,
            null);

        var advisory = GhsaMapper.Map(dto, documentRecord, DateTimeOffset.UtcNow);
        advisories.Add(advisory);
    }

        advisories.Sort((left, right) => string.Compare(left.AdvisoryKey, right.AdvisoryKey, StringComparison.Ordinal));
        var snapshot = SnapshotSerializer.ToSnapshot(advisories);
        File.WriteAllText(Path.Combine(fixturesPath, "osv-ghsa.ghsa.json"), snapshot);
        Console.WriteLine($"[FixtureUpdater] Updated {Path.Combine(fixturesPath, "osv-ghsa.ghsa.json")}");
    }
}

void RewriteCreditParityFixtures(string ghsaFixturesPath, string nvdFixturesPath)
{
    Directory.CreateDirectory(ghsaFixturesPath);
    Directory.CreateDirectory(nvdFixturesPath);

    var advisoryKeyGhsa = "GHSA-credit-parity";
    var advisoryKeyNvd = "CVE-2025-5555";
    var recordedAt = new DateTimeOffset(2025, 10, 10, 15, 0, 0, TimeSpan.Zero);
    var published = new DateTimeOffset(2025, 10, 9, 18, 30, 0, TimeSpan.Zero);
    var modified = new DateTimeOffset(2025, 10, 10, 12, 0, 0, TimeSpan.Zero);

    AdvisoryCredit[] CreateCredits(string source) =>
    [
        CreateCredit("Alice Researcher", "reporter", new[] { "mailto:alice.researcher@example.com" }, source),
        CreateCredit("Bob Maintainer", "remediation_developer", new[] { "https://github.com/acme/bob-maintainer" }, source)
    ];

    AdvisoryCredit CreateCredit(string displayName, string role, IReadOnlyList<string> contacts, string source)
    {
        var provenance = new AdvisoryProvenance(
            source,
            "credit",
            $"{source}:{displayName.ToLowerInvariant().Replace(' ', '-')}",
            recordedAt,
            new[] { ProvenanceFieldMasks.Credits });

        return new AdvisoryCredit(displayName, role, contacts, provenance);
    }

    AdvisoryReference[] CreateReferences(string sourceName, params (string Url, string Kind)[] entries)
    {
        if (entries is null || entries.Length == 0)
        {
            return Array.Empty<AdvisoryReference>();
        }

        var references = new List<AdvisoryReference>(entries.Length);
        foreach (var entry in entries)
        {
            var provenance = new AdvisoryProvenance(
                sourceName,
                "reference",
                entry.Url,
                recordedAt,
                new[] { ProvenanceFieldMasks.References });

            references.Add(new AdvisoryReference(
                entry.Url,
                entry.Kind,
                sourceTag: null,
                summary: null,
                provenance));
        }

        return references.ToArray();
    }

    Advisory CreateAdvisory(
        string sourceName,
        string advisoryKey,
        IEnumerable<string> aliases,
        AdvisoryCredit[] credits,
        AdvisoryReference[] references,
        string documentValue)
    {
        var documentProvenance = new AdvisoryProvenance(
            sourceName,
            "document",
            documentValue,
            recordedAt,
            new[] { ProvenanceFieldMasks.Advisory });
        var mappingProvenance = new AdvisoryProvenance(
            sourceName,
            "mapping",
            advisoryKey,
            recordedAt,
            new[] { ProvenanceFieldMasks.Advisory });

        return new Advisory(
            advisoryKey,
            "Credit parity regression fixture",
            "Credit parity regression fixture",
            "en",
            published,
            modified,
            "moderate",
            exploitKnown: false,
            aliases,
            credits,
            references,
            Array.Empty<AffectedPackage>(),
            Array.Empty<CvssMetric>(),
            new[] { documentProvenance, mappingProvenance });
    }

    var ghsa = CreateAdvisory(
        "ghsa",
        advisoryKeyGhsa,
        new[] { advisoryKeyGhsa, advisoryKeyNvd },
        CreateCredits("ghsa"),
        CreateReferences(
            "ghsa",
            ( $"https://github.com/advisories/{advisoryKeyGhsa}", "advisory"),
            ( "https://example.com/ghsa/patch", "patch")),
        $"security/advisories/{advisoryKeyGhsa}");

    var osv = CreateAdvisory(
        OsvConnectorPlugin.SourceName,
        advisoryKeyGhsa,
        new[] { advisoryKeyGhsa, advisoryKeyNvd },
        CreateCredits(OsvConnectorPlugin.SourceName),
        CreateReferences(
            OsvConnectorPlugin.SourceName,
            ( $"https://github.com/advisories/{advisoryKeyGhsa}", "advisory"),
            ( $"https://osv.dev/vulnerability/{advisoryKeyGhsa}", "advisory")),
        $"https://osv.dev/vulnerability/{advisoryKeyGhsa}");

    var nvd = CreateAdvisory(
        NvdConnectorPlugin.SourceName,
        advisoryKeyNvd,
        new[] { advisoryKeyNvd, advisoryKeyGhsa },
        CreateCredits(NvdConnectorPlugin.SourceName),
        CreateReferences(
            NvdConnectorPlugin.SourceName,
            ( $"https://services.nvd.nist.gov/vuln/detail/{advisoryKeyNvd}", "advisory"),
            ( "https://example.com/nvd/reference", "report")),
        $"https://services.nvd.nist.gov/vuln/detail/{advisoryKeyNvd}");

    var ghsaSnapshot = SnapshotSerializer.ToSnapshot(ghsa);
    var osvSnapshot = SnapshotSerializer.ToSnapshot(osv);
    var nvdSnapshot = SnapshotSerializer.ToSnapshot(nvd);

    File.WriteAllText(Path.Combine(ghsaFixturesPath, "credit-parity.ghsa.json"), ghsaSnapshot);
    File.WriteAllText(Path.Combine(ghsaFixturesPath, "credit-parity.osv.json"), osvSnapshot);
    File.WriteAllText(Path.Combine(ghsaFixturesPath, "credit-parity.nvd.json"), nvdSnapshot);

    File.WriteAllText(Path.Combine(nvdFixturesPath, "credit-parity.ghsa.json"), ghsaSnapshot);
    File.WriteAllText(Path.Combine(nvdFixturesPath, "credit-parity.osv.json"), osvSnapshot);
    File.WriteAllText(Path.Combine(nvdFixturesPath, "credit-parity.nvd.json"), nvdSnapshot);

    Console.WriteLine($"[FixtureUpdater] Updated credit parity fixtures under {ghsaFixturesPath} and {nvdFixturesPath}");
}