using System.Text.Json;
using FluentAssertions;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.DependencyInjection;
using StackExchange.Redis;

[Collection("Integration")]
public class WarningAlertTests : IAsyncLifetime
{
    private readonly ApiFixture _fixture;
    private Guid _patientId;
    private Guid _encounterId;

    public WarningAlertTests(ApiFixture fixture) => _fixture = fixture;

    public async Task InitializeAsync() => await ResetAndSeedAsync();

    public Task DisposeAsync() => Task.CompletedTask;

    private async Task ResetAndSeedAsync()
    {
        using var scope = _fixture.Services.CreateScope();
        var db = scope.ServiceProvider.GetRequiredService<AppDbContext>();
        await DbResetHelper.ResetAsync(db);

        var patient = new Patient
        {
            Id = Guid.NewGuid(), Mrn = "MRN-WA-001", FirstName = "Warning", LastName = "Test",
            DateOfBirth = new DateOnly(1975, 5, 20), Gender = "M", CreatedAt = DateTimeOffset.UtcNow
        };
        var encounter = new Encounter
        {
            Id = Guid.NewGuid(), PatientId = patient.Id, EncounterType = EncounterType.Inpatient,
            Status = EncounterStatus.Active, Department = Department.Icu,
            AttendingPhysician = "Dr. Warning", AdmittedAt = DateTimeOffset.UtcNow,
            CreatedAt = DateTimeOffset.UtcNow
        };
        db.Patients.Add(patient);
        db.Encounters.Add(encounter);
        db.AlertThresholds.Add(new AlertThreshold
        {
            Id = Guid.NewGuid(), ObservationCode = "HEART_RATE",
            DisplayName = "Heart Rate", Unit = "bpm",
            CriticalLow = 30, WarningLow = 50, WarningHigh = 100, CriticalHigh = 150,
            CreatedAt = DateTimeOffset.UtcNow
        });
        await db.SaveChangesAsync();

        var redis = scope.ServiceProvider.GetRequiredService<IConnectionMultiplexer>();
        var cache = redis.GetDatabase(1);
        await cache.StringSetAsync("threshold:HEART_RATE",
            """{"ObservationCode":"HEART_RATE","CriticalLow":30,"WarningLow":50,"WarningHigh":100,"CriticalHigh":150}""");

        _patientId = patient.Id;
        _encounterId = encounter.Id;
    }

    [Fact]
    public async Task WarningHeartRate_AlertCreated()
    {
        await ResetAndSeedAsync();

        using var scope = _fixture.Services.CreateScope();
        var evaluator = scope.ServiceProvider.GetRequiredService<WarningEvaluator>();

        var created = await evaluator.EvaluateAsync(
            Guid.NewGuid(), _encounterId, _patientId, "HEART_RATE", 105m);

        created.Should().BeTrue();

        var db = scope.ServiceProvider.GetRequiredService<AppDbContext>();
        var alert = await db.ClinicalAlerts.SingleAsync();
        alert.AlertType.Should().Be(AlertType.WarningHeartRate);
        alert.Severity.Should().Be(AlertSeverity.Warning);
        alert.Status.Should().Be(AlertStatus.Open);
    }

    [Fact]
    public async Task NormalHeartRate_NoAlert()
    {
        await ResetAndSeedAsync();

        using var scope = _fixture.Services.CreateScope();
        var evaluator = scope.ServiceProvider.GetRequiredService<WarningEvaluator>();

        var created = await evaluator.EvaluateAsync(
            Guid.NewGuid(), _encounterId, _patientId, "HEART_RATE", 78m);

        created.Should().BeFalse();

        var db = scope.ServiceProvider.GetRequiredService<AppDbContext>();
        (await db.ClinicalAlerts.CountAsync()).Should().Be(0);
    }

    [Fact]
    public async Task CriticalHeartRate_NoWarningAlert()
    {
        await ResetAndSeedAsync();

        using var scope = _fixture.Services.CreateScope();
        var evaluator = scope.ServiceProvider.GetRequiredService<WarningEvaluator>();

        var created = await evaluator.EvaluateAsync(
            Guid.NewGuid(), _encounterId, _patientId, "HEART_RATE", 160m);

        created.Should().BeFalse();

        var db = scope.ServiceProvider.GetRequiredService<AppDbContext>();
        (await db.ClinicalAlerts.CountAsync()).Should().Be(0);
    }

    [Fact]
    public async Task DuplicateWarning_Idempotent()
    {
        await ResetAndSeedAsync();

        using var scope = _fixture.Services.CreateScope();
        var evaluator = scope.ServiceProvider.GetRequiredService<WarningEvaluator>();

        await evaluator.EvaluateAsync(Guid.NewGuid(), _encounterId, _patientId, "HEART_RATE", 105m);
        await evaluator.EvaluateAsync(Guid.NewGuid(), _encounterId, _patientId, "HEART_RATE", 108m);

        var db = scope.ServiceProvider.GetRequiredService<AppDbContext>();
        (await db.ClinicalAlerts.CountAsync()).Should().Be(1,
            "second warning for same type must be idempotent while first is still open");
    }
}