using System.Net;
using System.Net.Http.Headers;
using System.Net.Http.Json;
using System.Text.Json;
using Dapper;
using FluentAssertions;
using Microsoft.Data.SqlClient;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.DependencyInjection.Extensions;
using NSubstitute;
using NSubstitute.ExceptionExtensions;
using SIGCM2.Application.Abstractions.Security;
using SIGCM2.Application.Audit;
using SIGCM2.Application.Common;
using SIGCM2.Application.Pricing.ChargeableChars;
using SIGCM2.Domain.Entities;
using SIGCM2.TestSupport;
using Xunit;

namespace SIGCM2.Api.Tests.Pricing.ChargeableChars;

/// <summary>
/// PRC-001 — E2E integration tests for:
///   GET    /api/v1/admin/chargeable-chars
///   GET    /api/v1/admin/chargeable-chars/{id}
///   POST   /api/v1/admin/chargeable-chars
///   PUT    /api/v1/admin/chargeable-chars/{id}/price
///   PATCH  /api/v1/admin/chargeable-chars/{id}/deactivate
///   PATCH  /api/v1/admin/chargeable-chars/{id}/reactivate
///   DELETE /api/v1/admin/chargeable-chars/{id}
///
/// DB: SIGCM2_Test_Api (ApiIntegration collection — shared TestWebAppFactory).
/// All mutations require 'tasacion:caracteres_especiales:gestionar' permission.
/// </summary>
[Collection("ApiIntegration")]
public sealed class ChargeableCharConfigControllerTests : IAsyncLifetime
{
    private const string ConnectionString = TestConnectionStrings.ApiTestDb;

    private readonly TestWebAppFactory _factory;
    private readonly HttpClient _client;

    public ChargeableCharConfigControllerTests(TestWebAppFactory factory)
    {
        _factory = factory;
        _client = factory.CreateClient();
    }

    public Task InitializeAsync() => Task.CompletedTask;
    public Task DisposeAsync() => Task.CompletedTask;

    // ── Auth helpers ──────────────────────────────────────────────────────────

    /// <summary>Admin token — has 'tasacion:caracteres_especiales:gestionar' via 'admin' role.</summary>
    private string GetAdminToken()
    {
        var jwt = _factory.Services.GetRequiredService<IJwtService>();
        return jwt.GenerateAccessToken(new Usuario(
            id: 1, username: "admin", passwordHash: "x",
            nombre: "Admin", apellido: "Sys", email: null,
            rol: "admin", permisosJson: """{"grant":[],"deny":[]}""", activo: true));
    }

    /// <summary>Cajero token — does NOT have 'tasacion:caracteres_especiales:gestionar'.</summary>
    private string GetCajeroToken()
    {
        var jwt = _factory.Services.GetRequiredService<IJwtService>();
        return jwt.GenerateAccessToken(new Usuario(
            id: 9999, username: "cajero_test", passwordHash: "x",
            nombre: "Cajero", apellido: "Test", email: null,
            rol: "cajero", permisosJson: """{"grant":[],"deny":[]}""", activo: true));
    }

    private HttpRequestMessage BuildRequest(
        HttpMethod method, string url, object? body = null, string? token = null)
    {
        var req = new HttpRequestMessage(method, url);
        if (token is not null)
            req.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
        if (body is not null)
            req.Content = JsonContent.Create(body);
        return req;
    }

    // ── DB seed helpers ───────────────────────────────────────────────────────

    /// <summary>Inserts a ChargeableCharConfig row directly (bypasses SP guard) for scenario setup.</summary>
    private async Task<long> SeedConfigDirectAsync(
        long? productTypeId, string symbol, string category, decimal pricePerUnit,
        DateOnly validFrom, DateOnly? validTo, bool isActive = true)
    {
        await using var conn = new SqlConnection(ConnectionString);
        await conn.OpenAsync();
        return await conn.QuerySingleAsync<long>("""
            INSERT INTO dbo.ChargeableCharConfig
                (ProductTypeId, Symbol, Category, PricePerUnit, ValidFrom, ValidTo, IsActive, FechaCreacion)
            VALUES (@ProductTypeId, @Symbol, @Category, @PricePerUnit, @ValidFrom, @ValidTo, @IsActive, SYSUTCDATETIME());
            SELECT CAST(SCOPE_IDENTITY() AS BIGINT);
            """,
            new
            {
                ProductTypeId = productTypeId.HasValue ? (object)(int)productTypeId.Value : DBNull.Value,
                Symbol = symbol,
                Category = category,
                PricePerUnit = pricePerUnit,
                ValidFrom = validFrom.ToDateTime(TimeOnly.MinValue),
                ValidTo = validTo.HasValue ? (object)validTo.Value.ToDateTime(TimeOnly.MinValue) : DBNull.Value,
                IsActive = isActive ? 1 : 0
            });
    }

    private static string TomorrowStr() =>
        DateOnly.FromDateTime(DateTime.UtcNow).AddDays(1).ToString("yyyy-MM-dd");

    private static string FutureDateStr(int daysAhead = 60) =>
        DateOnly.FromDateTime(DateTime.UtcNow).AddDays(daysAhead).ToString("yyyy-MM-dd");

    // ── GET /api/v1/admin/chargeable-chars ───────────────────────────────────

    /// <summary>PRC-001-R3.1 — GET list returns paged result.</summary>
    [Fact]
    public async Task Get_List_ReturnsPagedResult()
    {
        // Seed an active row with unique symbol to avoid conflicts
        await SeedConfigDirectAsync(null, "§", "Currency", 1.50m,
            new DateOnly(2026, 1, 1), null, true);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Get,
            "/api/v1/admin/chargeable-chars?activeOnly=true", token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.OK);
        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        body.TryGetProperty("items", out _).Should().BeTrue("response must have 'items' property");
        body.GetProperty("page").GetInt32().Should().BeGreaterThanOrEqualTo(1);
        body.GetProperty("pageSize").GetInt32().Should().BeGreaterThanOrEqualTo(1);
        body.GetProperty("total").GetInt32().Should().BeGreaterThanOrEqualTo(1);
    }

    [Fact]
    public async Task Get_List_Unauthenticated_Returns401()
    {
        using var req = BuildRequest(HttpMethod.Get, "/api/v1/admin/chargeable-chars");
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.Unauthorized);
    }

    [Fact]
    public async Task Get_List_WithoutPermission_Returns403()
    {
        var token = GetCajeroToken();
        using var req = BuildRequest(HttpMethod.Get, "/api/v1/admin/chargeable-chars", token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.Forbidden);
    }

    // ── GET /api/v1/admin/chargeable-chars/{id} ──────────────────────────────

    /// <summary>PRC-001-R3.1 — GET by id returns 200 + DTO.</summary>
    [Fact]
    public async Task Get_ById_Existing_Returns200()
    {
        var id = await SeedConfigDirectAsync(null, "€", "Currency", 2.00m,
            new DateOnly(2026, 1, 1), null, true);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Get,
            $"/api/v1/admin/chargeable-chars/{id}", token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.OK);
        var dto = await resp.Content.ReadFromJsonAsync<JsonElement>();
        dto.GetProperty("id").GetInt64().Should().Be(id);
        dto.GetProperty("symbol").GetString().Should().Be("€");
        dto.GetProperty("isActive").GetBoolean().Should().BeTrue();
    }

    /// <summary>PRC-001-R3.1 — GET by non-existent id returns 404.</summary>
    [Fact]
    public async Task Get_ByIdMissing_Returns404()
    {
        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Get,
            "/api/v1/admin/chargeable-chars/999999999", token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.NotFound);
    }

    // ── POST /api/v1/admin/chargeable-chars ──────────────────────────────────

    /// <summary>PRC-001-R3.2 — POST valid payload returns 201 + Location header.</summary>
    [Fact]
    public async Task Post_WithValidPayload_Returns201WithLocation()
    {
        var token = GetAdminToken();
        var validFrom = TomorrowStr();

        using var req = BuildRequest(HttpMethod.Post, "/api/v1/admin/chargeable-chars",
            body: new
            {
                productTypeId = (long?)null,
                symbol = "¥",
                category = "Currency",
                pricePerUnit = 1.75m,
                validFrom
            },
            token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.Created);
        resp.Headers.Location.Should().NotBeNull("201 must include Location header");

        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        body.GetProperty("id").GetInt64().Should().BeGreaterThan(0);
        body.GetProperty("symbol").GetString().Should().Be("¥");
        body.GetProperty("validFrom").GetString().Should().Be(validFrom);
    }

    /// <summary>PRC-001-R3.5 — POST without auth returns 401.</summary>
    [Fact]
    public async Task Post_Unauthenticated_Returns401()
    {
        using var req = BuildRequest(HttpMethod.Post, "/api/v1/admin/chargeable-chars",
            body: new { productTypeId = (long?)null, symbol = "£", category = "Currency", pricePerUnit = 1.0m, validFrom = TomorrowStr() });
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.Unauthorized);
    }

    /// <summary>PRC-001-R3.5 — POST without permission returns 403.</summary>
    [Fact]
    public async Task Post_WithoutPermission_Returns403()
    {
        var token = GetCajeroToken();
        using var req = BuildRequest(HttpMethod.Post, "/api/v1/admin/chargeable-chars",
            body: new { productTypeId = (long?)null, symbol = "£", category = "Currency", pricePerUnit = 1.0m, validFrom = TomorrowStr() },
            token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.Forbidden);
    }

    /// <summary>PRC-001-R3.2 — POST invalid price returns 400 validation failure.</summary>
    [Fact]
    public async Task Post_InvalidPrice_Returns400ValidationFailure()
    {
        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Post, "/api/v1/admin/chargeable-chars",
            body: new { productTypeId = (long?)null, symbol = "£", category = "Currency", pricePerUnit = 0m, validFrom = TomorrowStr() },
            token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.BadRequest);
    }

    /// <summary>PRC-001-R2.7 — POST with symbol too long returns 400.</summary>
    [Fact]
    public async Task Post_SymbolTooLong_Returns400()
    {
        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Post, "/api/v1/admin/chargeable-chars",
            body: new { productTypeId = (long?)null, symbol = "$$$$$", category = "Currency", pricePerUnit = 1.0m, validFrom = TomorrowStr() },
            token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.BadRequest);
    }

    /// <summary>PRC-001-R2.6 — POST with past validFrom returns 400.</summary>
    [Fact]
    public async Task Post_WithPastValidFrom_Returns400()
    {
        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Post, "/api/v1/admin/chargeable-chars",
            body: new { productTypeId = (long?)null, symbol = "£", category = "Currency", pricePerUnit = 1.0m, validFrom = "2020-01-01" },
            token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.BadRequest);
    }

    /// <summary>
    /// PRC-001-R2.7 — Emoji symbols are explicitly DEFERRED per spec.
    /// The ChargeableCharConfig Symbol field accepts any 1–4 char value including emojis.
    /// "😀" in C# has string.Length = 2 (UTF-16 surrogate pair), so it passes MaximumLength(4).
    /// This test documents the deferred behavior: emoji in Symbol is accepted at config level.
    /// The EmojiDetectedException applies only to WordCounterService (ad text, not config symbols).
    /// </summary>
    [Fact]
    public async Task Post_WithEmojiSymbol_Returns201_BecauseEmojiRejectionIsDeferred()
    {
        var token = GetAdminToken();
        // "😀" has C# string.Length == 2 (UTF-16 surrogate pair) — passes MaximumLength(4).
        // Emoji rejection for config Symbols is deferred to PRC-002+ per spec R2.7.
        using var req = BuildRequest(HttpMethod.Post, "/api/v1/admin/chargeable-chars",
            body: new { productTypeId = (long?)null, symbol = "😀", category = "Currency", pricePerUnit = 1.0m, validFrom = TomorrowStr() },
            token: token);
        var resp = await _client.SendAsync(req);
        // Accepted: emoji symbols deferred per spec. If business later rejects them, update validator + this test.
        resp.StatusCode.Should().Be(HttpStatusCode.Created,
            because: "emoji symbol rejection is deferred (spec R2.7). Symbol '😀' has length 2 in C# (UTF-16) → passes MaximumLength(4)");
    }

    // ── PUT /api/v1/admin/chargeable-chars/{id}/price ────────────────────────

    /// <summary>PRC-001-R3.3 — PUT schedules price change, returns 200.</summary>
    [Fact]
    public async Task Put_PriceChange_Returns200()
    {
        // Seed an active row
        var existingId = await SeedConfigDirectAsync(null, "★", "Currency", 1.00m,
            new DateOnly(2026, 1, 1), null, true);

        var token = GetAdminToken();
        var newValidFrom = FutureDateStr(30);

        using var req = BuildRequest(HttpMethod.Put,
            $"/api/v1/admin/chargeable-chars/{existingId}/price",
            body: new { pricePerUnit = 2.50m, validFrom = newValidFrom },
            token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.OK);
        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        body.GetProperty("newId").GetInt64().Should().BeGreaterThan(0);
        body.GetProperty("newValidFrom").GetString().Should().Be(newValidFrom);
    }

    /// <summary>PRC-001-R3.3 — PUT with retroactive date returns 409 ForwardOnly.</summary>
    [Fact]
    public async Task Put_PriceBackdateAttempt_Returns409()
    {
        // Seed an active row with a far-future ValidFrom
        var existingId = await SeedConfigDirectAsync(null, "♦", "Currency", 1.00m,
            new DateOnly(2099, 12, 1), null, true);

        var token = GetAdminToken();
        // Try to schedule before the existing ValidFrom
        using var req = BuildRequest(HttpMethod.Put,
            $"/api/v1/admin/chargeable-chars/{existingId}/price",
            body: new { pricePerUnit = 2.00m, validFrom = "2099-11-01" },
            token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.Conflict);
        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        body.GetProperty("error").GetString().Should().Be("chargeable_char_forward_only");
    }

    // ── PATCH /api/v1/admin/chargeable-chars/{id}/deactivate ────────────────

    /// <summary>PRC-001-R3.4 — PATCH deactivate returns 200 OK.</summary>
    [Fact]
    public async Task Patch_Deactivate_Returns200()
    {
        var id = await SeedConfigDirectAsync(null, "▲", "Currency", 1.00m,
            new DateOnly(2026, 1, 1), null, true);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Patch,
            $"/api/v1/admin/chargeable-chars/{id}/deactivate", token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.OK);
    }

    /// <summary>PRC-001 — PATCH deactivate on already-inactive row is idempotent → 200 OK.</summary>
    [Fact]
    public async Task Patch_Deactivate_AlreadyInactive_Returns200()
    {
        // Seed an already-inactive row
        var id = await SeedConfigDirectAsync(null, "▼", "Currency", 1.00m,
            new DateOnly(2026, 1, 1), new DateOnly(2026, 1, 31), false);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Patch,
            $"/api/v1/admin/chargeable-chars/{id}/deactivate", token: token);
        var resp = await _client.SendAsync(req);

        // Idempotent — no exception thrown
        resp.StatusCode.Should().Be(HttpStatusCode.OK);
    }

    // ── PATCH /api/v1/admin/chargeable-chars/{id}/reactivate ─────────────────

    /// <summary>PRC-001 — PATCH reactivate on last closed row returns 200.</summary>
    [Fact]
    public async Task Patch_Reactivate_LastClosed_Returns200()
    {
        // Seed a closed row (isActive=false) — no other active row for this symbol
        // Use a unique symbol to avoid conflicts with other tests
        var uniqueSymbol = $"R{Guid.NewGuid():N}"[..1];
        var id = await SeedConfigDirectAsync(null, uniqueSymbol, "Other", 0.50m,
            new DateOnly(2026, 1, 1), new DateOnly(2026, 4, 1), false);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Patch,
            $"/api/v1/admin/chargeable-chars/{id}/reactivate", token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.OK);
        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        body.GetProperty("id").GetInt64().Should().Be(id);
        body.GetProperty("isActive").GetBoolean().Should().BeTrue();
    }

    /// <summary>PRC-001 — PATCH reactivate on already-active row returns 409 ALREADY_ACTIVE.</summary>
    [Fact]
    public async Task Patch_Reactivate_AlreadyActive_Returns409_AlreadyActive()
    {
        var uniqueSymbol = $"A{Guid.NewGuid():N}"[..1];
        var id = await SeedConfigDirectAsync(null, uniqueSymbol, "Other", 0.50m,
            new DateOnly(2026, 1, 1), null, true); // already active

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Patch,
            $"/api/v1/admin/chargeable-chars/{id}/reactivate", token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.Conflict);
        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        body.GetProperty("code").GetString().Should().Be("CHARGEABLE_CHAR_REACTIVATION_NOT_ALLOWED");
        body.GetProperty("reason").GetString().Should().Be("ALREADY_ACTIVE");
    }

    /// <summary>PRC-001 — PATCH reactivate when vigente exists returns 409 VIGENTE_EXISTS.</summary>
    [Fact]
    public async Task Patch_Reactivate_VigenteExists_Returns409_VigenteExists()
    {
        // Seed: one active (vigente) row + one closed row for the same symbol
        var uniqueSymbol = $"V{Guid.NewGuid():N}"[..1];

        // First: closed row (older)
        var closedId = await SeedConfigDirectAsync(null, uniqueSymbol, "Other", 0.50m,
            new DateOnly(2026, 1, 1), new DateOnly(2026, 3, 31), false);

        // Second: active vigente row (newer — this blocks reactivation of closedId)
        await SeedConfigDirectAsync(null, uniqueSymbol, "Other", 1.00m,
            new DateOnly(2026, 4, 1), null, true);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Patch,
            $"/api/v1/admin/chargeable-chars/{closedId}/reactivate", token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.Conflict);
        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        body.GetProperty("code").GetString().Should().Be("CHARGEABLE_CHAR_REACTIVATION_NOT_ALLOWED");
        body.GetProperty("reason").GetString().Should().Be("VIGENTE_EXISTS");
    }

    /// <summary>PRC-001 — PATCH reactivate when posterior rows exist returns 409 POSTERIOR_ROWS_EXIST.</summary>
    [Fact]
    public async Task Patch_Reactivate_PosteriorRowsExist_Returns409_PosteriorRowsExist()
    {
        // Seed: target closed row + a posterior (newer ValidFrom) closed row for the same symbol
        var uniqueSymbol = $"P{Guid.NewGuid():N}"[..1];

        // First: target closed row
        var targetId = await SeedConfigDirectAsync(null, uniqueSymbol, "Other", 0.50m,
            new DateOnly(2026, 1, 1), new DateOnly(2026, 3, 31), false);

        // Second: posterior closed row (newer ValidFrom, also closed — blocks reactivation)
        await SeedConfigDirectAsync(null, uniqueSymbol, "Other", 1.00m,
            new DateOnly(2026, 4, 1), new DateOnly(2026, 6, 30), false);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Patch,
            $"/api/v1/admin/chargeable-chars/{targetId}/reactivate", token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.Conflict);
        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        body.GetProperty("code").GetString().Should().Be("CHARGEABLE_CHAR_REACTIVATION_NOT_ALLOWED");
        body.GetProperty("reason").GetString().Should().Be("POSTERIOR_ROWS_EXIST");
    }

    /// <summary>PRC-001 — PATCH reactivate without auth returns 401.</summary>
    [Fact]
    public async Task Patch_Reactivate_Unauthorized_Returns401()
    {
        using var req = BuildRequest(HttpMethod.Patch,
            "/api/v1/admin/chargeable-chars/1/reactivate");
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.Unauthorized);
    }

    /// <summary>PRC-001 — PATCH reactivate without permission returns 403.</summary>
    [Fact]
    public async Task Patch_Reactivate_WithoutPermission_Returns403()
    {
        var token = GetCajeroToken();
        using var req = BuildRequest(HttpMethod.Patch,
            "/api/v1/admin/chargeable-chars/1/reactivate", token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.Forbidden);
    }

    /// <summary>PRC-001 — PATCH reactivate emits audit event.</summary>
    [Fact]
    public async Task Patch_Reactivate_AuditEventEmitted()
    {
        var uniqueSymbol = $"Q{Guid.NewGuid():N}"[..1];
        var id = await SeedConfigDirectAsync(null, uniqueSymbol, "Other", 0.50m,
            new DateOnly(2026, 1, 1), new DateOnly(2026, 4, 1), false);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Patch,
            $"/api/v1/admin/chargeable-chars/{id}/reactivate", token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.OK,
            because: "PATCH reactivate must succeed before checking audit");

        await using var conn = new SqlConnection(ConnectionString);
        await conn.OpenAsync();
        var auditCount = await conn.QuerySingleAsync<int>("""
            SELECT COUNT(1) FROM dbo.AuditEvent
            WHERE Action = 'tasacion.chargeable_char.reactivate'
              AND TargetType = 'ChargeableCharConfig'
              AND TargetId = @TargetId
            """, new { TargetId = id.ToString() });

        auditCount.Should().Be(1,
            because: "IAuditLogger must record tasacion.chargeable_char.reactivate after successful PATCH");
    }

    // ── DELETE /api/v1/admin/chargeable-chars/{id} ───────────────────────────

    /// <summary>PRC-001 — DELETE existing row returns 200.</summary>
    [Fact]
    public async Task Delete_Existing_Returns200()
    {
        var uniqueSymbol = $"D{Guid.NewGuid():N}"[..1];
        var id = await SeedConfigDirectAsync(null, uniqueSymbol, "Other", 0.50m,
            new DateOnly(2026, 1, 1), null, true);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Delete,
            $"/api/v1/admin/chargeable-chars/{id}", token: token);
        var resp = await _client.SendAsync(req);

        resp.StatusCode.Should().Be(HttpStatusCode.OK);
        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        body.GetProperty("id").GetInt64().Should().Be(id);
    }

    /// <summary>PRC-001 — DELETE non-existent row returns 404.</summary>
    [Fact]
    public async Task Delete_NotFound_Returns404()
    {
        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Delete,
            "/api/v1/admin/chargeable-chars/999999998", token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.NotFound);
    }

    /// <summary>PRC-001 — DELETE emits audit event.</summary>
    [Fact]
    public async Task Delete_AuditEventEmitted()
    {
        var uniqueSymbol = $"E{Guid.NewGuid():N}"[..1];
        var id = await SeedConfigDirectAsync(null, uniqueSymbol, "Other", 0.50m,
            new DateOnly(2026, 1, 1), null, true);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Delete,
            $"/api/v1/admin/chargeable-chars/{id}", token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.OK,
            because: "DELETE must succeed before checking audit");

        await using var conn = new SqlConnection(ConnectionString);
        await conn.OpenAsync();
        var auditCount = await conn.QuerySingleAsync<int>("""
            SELECT COUNT(1) FROM dbo.AuditEvent
            WHERE Action = 'tasacion.chargeable_char.delete'
              AND TargetType = 'ChargeableCharConfig'
              AND TargetId = @TargetId
            """, new { TargetId = id.ToString() });

        auditCount.Should().Be(1,
            because: "IAuditLogger must record tasacion.chargeable_char.delete after successful DELETE");
    }

    /// <summary>PRC-001 — DELETE without auth returns 401.</summary>
    [Fact]
    public async Task Delete_Unauthorized_Returns401()
    {
        using var req = BuildRequest(HttpMethod.Delete,
            "/api/v1/admin/chargeable-chars/1");
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.Unauthorized);
    }

    /// <summary>PRC-001 — DELETE without permission returns 403.</summary>
    [Fact]
    public async Task Delete_WithoutPermission_Returns403()
    {
        var token = GetCajeroToken();
        using var req = BuildRequest(HttpMethod.Delete,
            "/api/v1/admin/chargeable-chars/1", token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.Forbidden);
    }

    // ── Audit ─────────────────────────────────────────────────────────────────

    /// <summary>PRC-001-R3.6 — POST emits audit event chargeable_char_config.created.</summary>
    [Fact]
    public async Task AuditEvent_EmittedOnCreate()
    {
        var token = GetAdminToken();
        var validFrom = TomorrowStr();

        using var req = BuildRequest(HttpMethod.Post, "/api/v1/admin/chargeable-chars",
            body: new { productTypeId = (long?)null, symbol = "↑", category = "Currency", pricePerUnit = 1.10m, validFrom },
            token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.Created,
            because: "POST must succeed before we can verify audit");

        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        var newId = body.GetProperty("id").GetInt64();

        await using var conn = new SqlConnection(ConnectionString);
        await conn.OpenAsync();
        var auditCount = await conn.QuerySingleAsync<int>("""
            SELECT COUNT(1) FROM dbo.AuditEvent
            WHERE Action = 'tasacion.chargeable_char.create'
              AND TargetType = 'ChargeableCharConfig'
              AND TargetId = @TargetId
            """, new { TargetId = newId.ToString() });

        auditCount.Should().Be(1,
            because: "IAuditLogger must record tasacion.chargeable_char.create after successful POST");
    }

    /// <summary>PRC-001-R3.6 — PUT price change emits audit event.</summary>
    [Fact]
    public async Task AuditEvent_EmittedOnPriceChange()
    {
        var existingId = await SeedConfigDirectAsync(null, "↗", "Currency", 1.00m,
            new DateOnly(2026, 1, 1), null, true);

        var token = GetAdminToken();
        var newValidFrom = FutureDateStr(45);

        using var req = BuildRequest(HttpMethod.Put,
            $"/api/v1/admin/chargeable-chars/{existingId}/price",
            body: new { pricePerUnit = 3.00m, validFrom = newValidFrom },
            token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.OK,
            because: "PUT must succeed before we can verify audit");

        var body = await resp.Content.ReadFromJsonAsync<JsonElement>();
        var newId = body.GetProperty("newId").GetInt64();

        await using var conn = new SqlConnection(ConnectionString);
        await conn.OpenAsync();
        var auditCount = await conn.QuerySingleAsync<int>("""
            SELECT COUNT(1) FROM dbo.AuditEvent
            WHERE Action = 'tasacion.chargeable_char.price_change'
              AND TargetType = 'ChargeableCharConfig'
              AND TargetId = @TargetId
            """, new { TargetId = newId.ToString() });

        auditCount.Should().Be(1,
            because: "IAuditLogger must record tasacion.chargeable_char.price_change after successful PUT");
    }

    /// <summary>PRC-001-R3.6 — PATCH deactivate emits audit event.</summary>
    [Fact]
    public async Task AuditEvent_EmittedOnDeactivate()
    {
        var id = await SeedConfigDirectAsync(null, "→", "Currency", 1.00m,
            new DateOnly(2026, 1, 1), null, true);

        var token = GetAdminToken();
        using var req = BuildRequest(HttpMethod.Patch,
            $"/api/v1/admin/chargeable-chars/{id}/deactivate", token: token);
        var resp = await _client.SendAsync(req);
        resp.StatusCode.Should().Be(HttpStatusCode.OK,
            because: "PATCH must succeed before we can verify audit");

        await using var conn = new SqlConnection(ConnectionString);
        await conn.OpenAsync();
        var auditCount = await conn.QuerySingleAsync<int>("""
            SELECT COUNT(1) FROM dbo.AuditEvent
            WHERE Action = 'tasacion.chargeable_char.deactivate'
              AND TargetType = 'ChargeableCharConfig'
              AND TargetId = @TargetId
            """, new { TargetId = id.ToString() });

        auditCount.Should().Be(1,
            because: "IAuditLogger must record tasacion.chargeable_char.deactivate after successful PATCH");
    }

    /// <summary>PRC-001-R3.7 — Audit failure rolls back insert (fail-closed).</summary>
    [Fact]
    public async Task Audit_Rollback_OnLoggerFailure()
    {
        await using var conn = new SqlConnection(ConnectionString);
        await conn.OpenAsync();

        var countBefore = await conn.ExecuteScalarAsync<int>(
            "SELECT COUNT(1) FROM dbo.ChargeableCharConfig");

        // Build a mock IAuditLogger that throws
        var throwingAudit = Substitute.For<IAuditLogger>();
        throwingAudit
            .LogAsync(Arg.Any<string>(), Arg.Any<string>(), Arg.Any<string>(),
                Arg.Any<object?>(), Arg.Any<CancellationToken>())
            .ThrowsAsync(new InvalidOperationException("audit down — simulated failure"));

        using var client = _factory.CreateClientWithOverrides(services =>
        {
            services.RemoveAll<IAuditLogger>();
            services.AddScoped<IAuditLogger>(_ => throwingAudit);
        });

        var jwt = _factory.Services.GetRequiredService<IJwtService>();
        var token = jwt.GenerateAccessToken(new Usuario(
            id: 1, username: "admin", passwordHash: "x",
            nombre: "Admin", apellido: "Sys", email: null,
            rol: "admin", permisosJson: """{"grant":[],"deny":[]}""", activo: true));

        var req = new HttpRequestMessage(HttpMethod.Post, "/api/v1/admin/chargeable-chars");
        req.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
        req.Content = JsonContent.Create(new
        {
            productTypeId = (long?)null,
            symbol = "←",
            category = "Currency",
            pricePerUnit = 1.50m,
            validFrom = TomorrowStr()
        });

        // Act
        var resp = await client.SendAsync(req);

        // Audit throws → unhandled → 500
        resp.StatusCode.Should().Be(HttpStatusCode.InternalServerError,
            because: "audit failure must propagate as 500 (fail-closed)");

        // DB: no row was inserted
        await using var verifyConn = new SqlConnection(ConnectionString);
        await verifyConn.OpenAsync();
        var countAfter = await verifyConn.ExecuteScalarAsync<int>(
            "SELECT COUNT(1) FROM dbo.ChargeableCharConfig");

        countAfter.Should().Be(countBefore,
            because: "TransactionScope must roll back ChargeableCharConfig insert when audit fails");
    }
}