using System.Net;
using System.Net.Http.Headers;
using System.Text.Json;
using Azaion.Missions.E2E.Fixtures;
using Azaion.Missions.E2E.Helpers;
using Xunit;

namespace Azaion.Missions.E2E.Tests.Missions;

/// <summary>
/// FT-P-12 — mission cascade delete walks every dependency table.
/// Owns its own xUnit collection (<c>CascadeF3</c>) because the F3 fixture
/// is destructive and must run with a fresh DB per scenario.
/// Compares per-table counts against
/// <c>_docs/00_problem/input_data/expected_results/cascade_F3_walk.json</c>
/// via deep JSON diff (results_report.md row 3.1).
/// </summary>
[Collection("CascadeF3")]
[Trait("Category", "Blackbox")]
[Trait("db_access", "seed-or-assert-only")]
public sealed class CascadeF3Tests : TestBase, IClassFixture<CascadeF3Fixture>
{
    public CascadeF3Tests(CascadeF3Fixture _) { /* fixture seeds the DB. */ }

    [Fact]
    [Trait("Traces", "AC-3.1")]
    [Trait("max_ms", "10000")]
    public async Task FT_P_12_mission_cascade_walks_every_dependency_table()
    {
        // Arrange — load the canonical walk JSON to assert pre-state and post-state.
        // The expected_results directory is mounted directly at /app/fixtures
        // (see docker-compose.test.yml e2e-consumer volumes), so SQL fixtures
        // and JSON walks live side-by-side under the same root.
        var walkJson = JsonDocument.Parse(File.ReadAllText(
            Path.Combine(
                Environment.GetEnvironmentVariable("FIXTURE_SQL_DIR") ?? "/app/fixtures",
                "cascade_F3_walk.json")));
        var preState = walkJson.RootElement.GetProperty("expected_per_table_pre_state_for_safety_check");

        // Refresh the F3 fixture into a known state — IClassFixture seeds once
        // per class, but we want a clean walk for this single scenario.
        DbResetFixture.ResetDatabase(TestEnvironment.DbSideChannel);
        StubSchema.EnsureCreated();
        Seeds.Apply(FixtureSql.Load("fixture_cascade_F3"));

        // Sanity-check the pre-state — if the seed fixture failed silently, the
        // post-state assertions would trivially pass and mask the failure.
        Assert.Equal(preState.GetProperty("missions").GetInt32(),
            (int)DbAssertions.TableRowCount("missions"));
        Assert.Equal(preState.GetProperty("waypoints").GetInt32(),
            (int)DbAssertions.TableRowCount("waypoints"));
        Assert.Equal(preState.GetProperty("map_objects").GetInt32(),
            (int)DbAssertions.TableRowCount("map_objects"));
        Assert.Equal(preState.GetProperty("media").GetInt32(),
            (int)DbAssertions.TableRowCount("media"));
        Assert.Equal(preState.GetProperty("annotations").GetInt32(),
            (int)DbAssertions.TableRowCount("annotations"));
        Assert.Equal(preState.GetProperty("detection").GetInt32(),
            (int)DbAssertions.TableRowCount("detection"));

        var token = await Tokens.MintDefaultAsync();

        // Act
        using var http = new HttpRequestMessage(
            HttpMethod.Delete, $"/missions/{CascadeF3Fixture.MissionId}");
        http.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token.Jwt);
        using var response = await Missions.SendAsync(http);

        // Assert
        await HttpAssertions.AssertStatusAsync(response, HttpStatusCode.NoContent);
        var bodyLength = (await response.Content.ReadAsByteArrayAsync()).Length;
        Assert.Equal(0, bodyLength);

        // The walk JSON pins per-table post-state filters; assert each one.
        var postState = walkJson.RootElement.GetProperty("expected_per_table_post_state");
        AssertCount("missions",     "id = '22222222-0000-0000-0000-000000000001'", 0);
        AssertCount("waypoints",    "mission_id = '22222222-0000-0000-0000-000000000001'", 0);
        AssertCount("map_objects",  "mission_id = '22222222-0000-0000-0000-000000000001'", 0);
        AssertCount("media",        "id IN ('media-fixture-001', 'media-fixture-002')", 0);
        AssertCount("annotations",  "id IN ('anno-fixture-001', 'anno-fixture-002')", 0);
        AssertCount("detection",    "annotation_id IN ('anno-fixture-001', 'anno-fixture-002')", 0);

        // Sanity: the walk JSON has the same expectations we just asserted — fail
        // loudly if the JSON is out of sync with the in-source filters.
        Assert.Equal(0, postState.GetProperty("missions").GetProperty("expected_count").GetInt32());
    }

    private static void AssertCount(string table, string filterSql, long expected)
    {
        if (!table.All(c => char.IsLetterOrDigit(c) || c == '_'))
            throw new ArgumentException($"unsafe table identifier '{table}'", nameof(table));
        var actual = DbAssertions.ScalarCount($"SELECT COUNT(*) FROM {table} WHERE {filterSql}");
        Assert.Equal(expected, actual);
    }
}