// -----------------------------------------------------------------------------
// StellaOps.Notify.WebService.Tests / W1 / NotifyWebServiceContractTests.cs
// W1 contract tests for Notify.WebService endpoints (send notification, query status) — OpenAPI snapshot.
// Task: NOTIFY-5100-012
// -----------------------------------------------------------------------------

using System;
using System.Collections.Generic;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;
using System.Text.Json.Nodes;
using System.Threading.Tasks;
using FluentAssertions;
using Microsoft.AspNetCore.Mvc.Testing;
using Microsoft.AspNetCore.TestHost;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Xunit;
using Xunit.v3;

namespace StellaOps.Notify.WebService.Tests.W1;

/// <summary>
/// W1 contract tests for Notify WebService endpoints.
/// Tests verify endpoint contracts (request/response shapes), status codes,
/// and OpenAPI compliance.
/// </summary>
public class NotifyWebServiceContractTests : IClassFixture<WebApplicationFactory<Program>>, IAsyncLifetime
{
    private const string SigningKey = "super-secret-test-key-for-contract-tests-1234567890";
    private const string Issuer = "test-issuer";
    private const string Audience = "notify";
    private const string TestTenantId = "tenant-contract-test";

    private readonly WebApplicationFactory<Program> _factory;
    private readonly string _operatorToken;
    private readonly string _viewerToken;
    private readonly string _adminToken;

    public NotifyWebServiceContractTests(WebApplicationFactory<Program> factory)
    {
        _factory = factory.WithWebHostBuilder(builder =>
        {
            builder.ConfigureAppConfiguration((_, config) =>
            {
                config.AddInMemoryCollection(new Dictionary<string, string?>
                {
                    ["notify:storage:driver"] = "memory",
                    ["notify:authority:enabled"] = "false",
                    ["notify:authority:developmentSigningKey"] = SigningKey,
                    ["notify:authority:issuer"] = Issuer,
                    ["notify:authority:audiences:0"] = Audience,
                    ["notify:authority:allowAnonymousFallback"] = "false",
                    ["notify:authority:adminScope"] = "notify.admin",
                    ["notify:authority:operatorScope"] = "notify.operator",
                    ["notify:authority:viewerScope"] = "notify.viewer",
                    ["notify:telemetry:enableRequestLogging"] = "false",
                });
            });
            builder.ConfigureTestServices(services =>
            {
                NotifyTestServiceOverrides.ReplaceWithInMemory(services, signingKey: SigningKey, issuer: Issuer, audience: Audience);
            });
        });

        _viewerToken = CreateToken("notify.viewer");
        _operatorToken = CreateToken("notify.viewer", "notify.operator");
        _adminToken = CreateToken("notify.viewer", "notify.operator", "notify.admin");
    }

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

    #region Health Endpoints Contract

    [Fact]
    public async Task HealthEndpoint_ReturnsOkWithStatus()
    {
        // Arrange
        var client = _factory.CreateClient();

        // Act
        var response = await client.GetAsync("/healthz", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.OK);
        var content = await response.Content.ReadAsStringAsync(CancellationToken.None);
        var json = JsonNode.Parse(content);
        json?["status"]?.GetValue<string>().Should().Be("ok");
    }

    [Fact]
    public async Task ReadyEndpoint_ReturnsHealthStatus()
    {
        // Arrange
        var client = _factory.CreateClient();

        // Act
        var response = await client.GetAsync("/readyz", CancellationToken.None);

        // Assert
        response.StatusCode.Should().BeOneOf(HttpStatusCode.OK, HttpStatusCode.ServiceUnavailable);
    }

    #endregion

    #region Rules Endpoints Contract

    [Fact]
    public async Task ListRules_ReturnsJsonArray()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_viewerToken);

        // Act
        var response = await client.GetAsync("/api/v1/notify/rules", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.OK);
        response.Content.Headers.ContentType?.MediaType.Should().Be("application/json");

        var content = await response.Content.ReadAsStringAsync(CancellationToken.None);
        var json = JsonNode.Parse(content);
        json.Should().NotBeNull();
        json!.AsArray().Should().NotBeNull();
    }

    [Fact]
    public async Task CreateRule_ValidPayload_Returns201WithLocation()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_operatorToken);

        var ruleId = Guid.NewGuid().ToString();
        var payload = CreateRulePayload(ruleId);

        // Act
        var response = await client.PostAsync(
            "/api/v1/notify/rules",
            new StringContent(payload.ToJsonString(), Encoding.UTF8, "application/json"),
            CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.Created);
        response.Headers.Location.Should().NotBeNull();
        response.Headers.Location!.ToString().Should().Contain(ruleId);
    }

    [Fact]
    public async Task CreateRule_InvalidPayload_Returns400()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_operatorToken);

        var invalidPayload = new JsonObject { ["invalid"] = "data" };

        // Act
        var response = await client.PostAsync(
            "/api/v1/notify/rules",
            new StringContent(invalidPayload.ToJsonString(), Encoding.UTF8, "application/json"));

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.BadRequest);
    }

    [Fact]
    public async Task GetRule_NotFound_Returns404()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_viewerToken);

        // Act
        var response = await client.GetAsync($"/api/v1/notify/rules/{Guid.NewGuid()}", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.NotFound);
    }

    [Fact]
    public async Task DeleteRule_Existing_Returns204()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_operatorToken);

        // First create a rule
        var ruleId = Guid.NewGuid().ToString();
        var payload = CreateRulePayload(ruleId);
        await client.PostAsync(
            "/api/v1/notify/rules",
            new StringContent(payload.ToJsonString(), Encoding.UTF8, "application/json"),
            CancellationToken.None);

        // Act
        var response = await client.DeleteAsync($"/api/v1/notify/rules/{ruleId}", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.NoContent);
    }

    #endregion

    #region Channels Endpoints Contract

    [Fact]
    public async Task ListChannels_ReturnsJsonArray()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_viewerToken);

        // Act
        var response = await client.GetAsync("/api/v1/notify/channels", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.OK);
        response.Content.Headers.ContentType?.MediaType.Should().Be("application/json");

        var content = await response.Content.ReadAsStringAsync(CancellationToken.None);
        var json = JsonNode.Parse(content);
        json.Should().NotBeNull();
        json!.AsArray().Should().NotBeNull();
    }

    [Fact]
    public async Task CreateChannel_ValidPayload_Returns201()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_operatorToken);

        var channelId = Guid.NewGuid().ToString();
        var payload = CreateChannelPayload(channelId);

        // Act
        var response = await client.PostAsync(
            "/api/v1/notify/channels",
            new StringContent(payload.ToJsonString(), Encoding.UTF8, "application/json"),
            CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.Created);
    }

    #endregion

    #region Templates Endpoints Contract

    [Fact]
    public async Task ListTemplates_ReturnsJsonArray()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_viewerToken);

        // Act
        var response = await client.GetAsync("/api/v1/notify/templates", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.OK);
        var content = await response.Content.ReadAsStringAsync(CancellationToken.None);
        var json = JsonNode.Parse(content);
        json.Should().NotBeNull();
        json!.AsArray().Should().NotBeNull();
    }

    [Fact]
    public async Task CreateTemplate_ValidPayload_Returns201()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_operatorToken);

        var templateId = Guid.NewGuid();
        var payload = CreateTemplatePayload(templateId);

        // Act
        var response = await client.PostAsync(
            "/api/v1/notify/templates",
            new StringContent(payload.ToJsonString(), Encoding.UTF8, "application/json"),
            CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.Created);
    }

    #endregion

    #region Deliveries Endpoints Contract

    [Fact]
    public async Task CreateDelivery_ValidPayload_Returns201OrAccepted()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_operatorToken);

        var deliveryId = Guid.NewGuid();
        var payload = CreateDeliveryPayload(deliveryId);

        // Act
        var response = await client.PostAsync(
            "/api/v1/notify/deliveries",
            new StringContent(payload.ToJsonString(), Encoding.UTF8, "application/json"),
            CancellationToken.None);

        // Assert - can be 201 Created or 202 Accepted depending on processing
        response.StatusCode.Should().BeOneOf(HttpStatusCode.Created, HttpStatusCode.Accepted);
    }

    [Fact]
    public async Task ListDeliveries_ReturnsJsonArrayWithPagination()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_viewerToken);

        // Act
        var response = await client.GetAsync("/api/v1/notify/deliveries?limit=10", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.OK);
        var content = await response.Content.ReadAsStringAsync(CancellationToken.None);
        var json = JsonNode.Parse(content);
        json.Should().NotBeNull();
    }

    [Fact]
    public async Task GetDelivery_NotFound_Returns404()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_viewerToken);

        // Act
        var response = await client.GetAsync($"/api/v1/notify/deliveries/{Guid.NewGuid()}", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.NotFound);
    }

    #endregion

    #region Normalize Endpoints Contract (Internal)

    [Fact]
    public async Task NormalizeRule_ValidPayload_ReturnsUpgradedSchema()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_adminToken);

        var payload = CreateRulePayload(Guid.NewGuid().ToString());

        // Act
        var response = await client.PostAsync(
            "/internal/notify/rules/normalize",
            new StringContent(payload.ToJsonString(), Encoding.UTF8, "application/json"),
            CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.OK);
        var content = await response.Content.ReadAsStringAsync(CancellationToken.None);
        var json = JsonNode.Parse(content);
        json?["schemaVersion"]?.GetValue<string>().Should().NotBeNullOrEmpty();
    }

    #endregion

    #region Response Shape Validation

    [Fact]
    public async Task RuleResponse_ContainsRequiredFields()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_operatorToken);

        var ruleId = Guid.NewGuid().ToString();
        var payload = CreateRulePayload(ruleId);
        await client.PostAsync(
            "/api/v1/notify/rules",
            new StringContent(payload.ToJsonString(), Encoding.UTF8, "application/json"),
            CancellationToken.None);

        // Act
        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", _viewerToken);
        var response = await client.GetAsync($"/api/v1/notify/rules/{ruleId}", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.OK);
        var content = await response.Content.ReadAsStringAsync(CancellationToken.None);
        var json = JsonNode.Parse(content);

        // Verify required fields exist
        json?["ruleId"].Should().NotBeNull();
        json?["tenantId"].Should().NotBeNull();
        json?["schemaVersion"].Should().NotBeNull();
        json?["name"].Should().NotBeNull();
        json?["enabled"].Should().NotBeNull();
        json?["actions"].Should().NotBeNull();
    }

    [Fact]
    public async Task ChannelResponse_ContainsRequiredFields()
    {
        // Arrange
        var client = CreateAuthenticatedClient(_operatorToken);

        var channelId = Guid.NewGuid().ToString();
        var payload = CreateChannelPayload(channelId);
        await client.PostAsync(
            "/api/v1/notify/channels",
            new StringContent(payload.ToJsonString(), Encoding.UTF8, "application/json"),
            CancellationToken.None);

        // Act
        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", _viewerToken);
        var response = await client.GetAsync($"/api/v1/notify/channels/{channelId}", CancellationToken.None);

        // Assert
        response.StatusCode.Should().Be(HttpStatusCode.OK);
        var content = await response.Content.ReadAsStringAsync(CancellationToken.None);
        var json = JsonNode.Parse(content);

        json?["channelId"].Should().NotBeNull();
        json?["tenantId"].Should().NotBeNull();
        json?["type"].Should().NotBeNull();
        json?["name"].Should().NotBeNull();
    }

    #endregion

    #region Helper Methods

    private HttpClient CreateAuthenticatedClient(string token)
    {
        var client = _factory.CreateClient();
        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token);
        client.DefaultRequestHeaders.Add("X-StellaOps-Tenant", TestTenantId);
        return client;
    }

    private static string CreateToken(params string[] scopes)
    {
        return NotifyTestServiceOverrides.CreateTestToken(
            SigningKey, Issuer, Audience, scopes, tenantId: TestTenantId);
    }

    private static JsonObject CreateRulePayload(string ruleId)
    {
        return new JsonObject
        {
            ["schemaVersion"] = "notify.rule@1",
            ["ruleId"] = ruleId,
            ["tenantId"] = TestTenantId,
            ["name"] = $"Test Rule {ruleId}",
            ["description"] = "Contract test rule",
            ["enabled"] = true,
            ["match"] = new JsonObject
            {
                ["eventKinds"] = new JsonArray { "scan.completed" }
            },
            ["actions"] = new JsonArray
            {
                new JsonObject
                {
                    ["actionId"] = Guid.NewGuid().ToString(),
                    ["channel"] = Guid.NewGuid().ToString(),
                    ["template"] = "default",
                    ["enabled"] = true
                }
            }
        };
    }

    private static JsonObject CreateChannelPayload(string channelId)
    {
        return new JsonObject
        {
            ["schemaVersion"] = "notify.channel@1",
            ["channelId"] = channelId,
            ["tenantId"] = TestTenantId,
            ["type"] = "email",
            ["name"] = $"Test Channel {channelId}",
            ["enabled"] = true,
            ["config"] = new JsonObject
            {
                ["secretRef"] = "vault://notify/channels/test",
                ["target"] = "test@example.com"
            }
        };
    }

    private static JsonObject CreateTemplatePayload(Guid templateId)
    {
        return new JsonObject
        {
            ["schemaVersion"] = "notify.template@1",
            ["templateId"] = templateId.ToString(),
            ["tenantId"] = TestTenantId,
            ["channelType"] = "email",
            ["key"] = "scan-report",
            ["locale"] = "en",
            ["body"] = "Scan completed for {{event.payload.image}}",
            ["renderMode"] = "markdown"
        };
    }

    private static JsonObject CreateDeliveryPayload(Guid deliveryId)
    {
        return new JsonObject
        {
            ["deliveryId"] = deliveryId.ToString(),
            ["tenantId"] = TestTenantId,
            ["ruleId"] = Guid.NewGuid().ToString(),
            ["actionId"] = Guid.NewGuid().ToString(),
            ["eventId"] = Guid.NewGuid().ToString(),
            ["kind"] = "scanner.report.ready",
            ["status"] = "pending"
        };
    }

    #endregion
}