using StellaOps.Auth.Abstractions;
using StellaOps.Auth.ServerIntegration.Tenancy;
using StellaOps.Signals.Hosting;
using StellaOps.Signals.Options;
using StellaOps.Signals.Routing;

namespace StellaOps.Signals;

internal static class CompatibilityApiV1Endpoints
{
    private static readonly CompatibilitySignalRecord[] Signals =
    [
        new(
            "sig-001",
            "ci_build",
            "gitea",
            "completed",
            new Dictionary<string, object?>
            {
                ["host"] = "build-agent-01",
                ["runtime"] = "ebpf",
                ["probeStatus"] = "healthy",
                ["latencyMs"] = 41
            },
            "corr-001",
            "sha256:001",
            new[] { "update-runtime-health" },
            "2026-03-09T08:10:00Z",
            "2026-03-09T08:10:02Z",
            null),
        new(
            "sig-002",
            "ci_deploy",
            "internal",
            "processing",
            new Dictionary<string, object?>
            {
                ["host"] = "deploy-stage-02",
                ["runtime"] = "etw",
                ["probeStatus"] = "degraded",
                ["latencyMs"] = 84
            },
            "corr-002",
            "sha256:002",
            new[] { "refresh-rollout-state" },
            "2026-03-09T08:12:00Z",
            null,
            null),
        new(
            "sig-003",
            "registry_push",
            "harbor",
            "failed",
            new Dictionary<string, object?>
            {
                ["host"] = "registry-sync-01",
                ["runtime"] = "dyld",
                ["probeStatus"] = "failed",
                ["latencyMs"] = 132
            },
            "corr-003",
            "sha256:003",
            new[] { "retry-mirror" },
            "2026-03-09T08:13:00Z",
            "2026-03-09T08:13:05Z",
            "Registry callback timed out."),
        new(
            "sig-004",
            "scan_complete",
            "internal",
            "completed",
            new Dictionary<string, object?>
            {
                ["host"] = "scanner-03",
                ["runtime"] = "ebpf",
                ["probeStatus"] = "healthy",
                ["latencyMs"] = 58
            },
            "corr-004",
            "sha256:004",
            new[] { "refresh-risk-snapshot" },
            "2026-03-09T08:16:00Z",
            "2026-03-09T08:16:01Z",
            null),
        new(
            "sig-005",
            "policy_eval",
            "internal",
            "received",
            new Dictionary<string, object?>
            {
                ["host"] = "policy-runner-01",
                ["runtime"] = "unknown",
                ["probeStatus"] = "degraded",
                ["latencyMs"] = 73
            },
            "corr-005",
            "sha256:005",
            new[] { "await-policy-evaluation" },
            "2026-03-09T08:18:00Z",
            null,
            null)
    ];

    public static IEndpointRouteBuilder MapSignalsCompatibilityEndpoints(this IEndpointRouteBuilder app)
    {
        var group = app.MapGroup("/api/v1/signals").RequireTenant();

        group.MapGet("", (
            HttpContext context,
            SignalsOptions options,
            SignalsSealedModeMonitor sealedModeMonitor,
            string? type,
            string? status,
            string? provider,
            int? limit,
            string? cursor) =>
        {
            if (!Program.TryAuthorizeAny(context, [SignalsPolicies.Read, StellaOpsScopes.OrchRead], options.Authority.AllowAnonymousFallback, out var authFailure))
            {
                return authFailure ?? Results.Unauthorized();
            }

            if (!Program.TryEnsureSealedMode(sealedModeMonitor, out var sealedFailure))
            {
                return sealedFailure ?? Results.StatusCode(StatusCodes.Status503ServiceUnavailable);
            }

            var filtered = ApplyFilters(type, status, provider);
            var offset = ParseCursor(cursor);
            var pageSize = Math.Clamp(limit ?? 50, 1, 200);
            var items = filtered.Skip(offset).Take(pageSize).ToArray();
            var nextCursor = offset + pageSize < filtered.Length ? (offset + pageSize).ToString() : null;

            return Results.Ok(new
            {
                items,
                total = filtered.Length,
                cursor = nextCursor
            });
        });

        group.MapGet("/stats", (
            HttpContext context,
            SignalsOptions options,
            SignalsSealedModeMonitor sealedModeMonitor) =>
        {
            if (!Program.TryAuthorizeAny(context, [SignalsPolicies.Read, StellaOpsScopes.OrchRead], options.Authority.AllowAnonymousFallback, out var authFailure))
            {
                return authFailure ?? Results.Unauthorized();
            }

            if (!Program.TryEnsureSealedMode(sealedModeMonitor, out var sealedFailure))
            {
                return sealedFailure ?? Results.StatusCode(StatusCodes.Status503ServiceUnavailable);
            }

            return Results.Ok(BuildStats(Signals));
        });

        return app;
    }

    private static CompatibilitySignalRecord[] ApplyFilters(string? type, string? status, string? provider) =>
        Signals
            .Where(signal => string.IsNullOrWhiteSpace(type) || string.Equals(signal.Type, type, StringComparison.OrdinalIgnoreCase))
            .Where(signal => string.IsNullOrWhiteSpace(status) || string.Equals(signal.Status, status, StringComparison.OrdinalIgnoreCase))
            .Where(signal => string.IsNullOrWhiteSpace(provider) || string.Equals(signal.Provider, provider, StringComparison.OrdinalIgnoreCase))
            .ToArray();

    private static int ParseCursor(string? cursor) =>
        int.TryParse(cursor, out var offset) && offset >= 0 ? offset : 0;

    private static object BuildStats(IReadOnlyCollection<CompatibilitySignalRecord> signals)
    {
        var byType = signals
            .GroupBy(signal => signal.Type, StringComparer.OrdinalIgnoreCase)
            .ToDictionary(group => group.Key, group => group.Count(), StringComparer.OrdinalIgnoreCase);
        var byStatus = signals
            .GroupBy(signal => signal.Status, StringComparer.OrdinalIgnoreCase)
            .ToDictionary(group => group.Key, group => group.Count(), StringComparer.OrdinalIgnoreCase);
        var byProvider = signals
            .GroupBy(signal => signal.Provider, StringComparer.OrdinalIgnoreCase)
            .ToDictionary(group => group.Key, group => group.Count(), StringComparer.OrdinalIgnoreCase);
        var successful = signals.Count(signal => string.Equals(signal.Status, "completed", StringComparison.OrdinalIgnoreCase));
        var latencySamples = signals
            .Select(signal => signal.Payload.TryGetValue("latencyMs", out var value) ? value : null)
            .OfType<int>()
            .ToArray();

        return new
        {
            total = signals.Count,
            byType,
            byStatus,
            byProvider,
            lastHourCount = signals.Count,
            successRate = signals.Count == 0 ? 100 : Math.Round((successful / (double)signals.Count) * 100, 2),
            avgProcessingMs = latencySamples.Length == 0 ? 0 : Math.Round(latencySamples.Average(), 2)
        };
    }

    internal sealed record CompatibilitySignalRecord(
        string Id,
        string Type,
        string Provider,
        string Status,
        IReadOnlyDictionary<string, object?> Payload,
        string? CorrelationId,
        string? ArtifactRef,
        IReadOnlyCollection<string> TriggeredActions,
        string ReceivedAt,
        string? ProcessedAt,
        string? Error);
}