using Microsoft.AspNetCore.Mvc;
using StellaOps.Policy.Engine.Violations;

namespace StellaOps.Policy.Engine.Endpoints;

public static class ViolationEndpoint
{
    public static IEndpointRouteBuilder MapViolations(this IEndpointRouteBuilder routes)
    {
        routes.MapPost("/policy/violations/events", EmitEventsAsync)
            .WithName("PolicyEngine.Violations.Events");

        routes.MapPost("/policy/violations/severity", FuseAsync)
            .WithName("PolicyEngine.Violations.Severity");

        routes.MapPost("/policy/violations/conflicts", ConflictsAsync)
            .WithName("PolicyEngine.Violations.Conflicts");

        return routes;
    }

    private static async Task<IResult> EmitEventsAsync(
        [FromBody] ViolationEventRequest request,
        ViolationEventService service,
        CancellationToken cancellationToken)
    {
        try
        {
            var events = await service.EmitAsync(request, cancellationToken).ConfigureAwait(false);
            return Results.Json(new { events });
        }
        catch (Exception ex) when (ex is ArgumentException or KeyNotFoundException)
        {
            return Results.BadRequest(new { message = ex.Message });
        }
    }

    private static async Task<IResult> FuseAsync(
        [FromBody] ViolationEventRequest request,
        ViolationEventService eventService,
        SeverityFusionService fusionService,
        CancellationToken cancellationToken)
    {
        try
        {
            await eventService.EmitAsync(request, cancellationToken).ConfigureAwait(false);
            var fused = await fusionService.FuseAsync(request.SnapshotId, cancellationToken).ConfigureAwait(false);
            return Results.Json(new { fused });
        }
        catch (Exception ex) when (ex is ArgumentException or KeyNotFoundException)
        {
            return Results.BadRequest(new { message = ex.Message });
        }
    }

    private static async Task<IResult> ConflictsAsync(
        [FromBody] ConflictRequest request,
        ViolationEventService eventService,
        SeverityFusionService fusionService,
        ConflictHandlingService conflictService,
        CancellationToken cancellationToken)
    {
        try
        {
            await eventService.EmitAsync(new ViolationEventRequest(request.SnapshotId), cancellationToken).ConfigureAwait(false);
            var fused = await fusionService.FuseAsync(request.SnapshotId, cancellationToken).ConfigureAwait(false);
            var conflicts = await conflictService.ComputeAsync(request.SnapshotId, fused, cancellationToken).ConfigureAwait(false);
            return Results.Json(new { conflicts });
        }
        catch (Exception ex) when (ex is ArgumentException or KeyNotFoundException)
        {
            return Results.BadRequest(new { message = ex.Message });
        }
    }
}