using System.Security.Cryptography;
using System.Text;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using w4c_workflows.Data;
using w4c_workflows.Models;
using w4c_workflows.Services;
using Xunit;

namespace w4c_workflows.Tests;

[Collection("WorkflowsPostgres")]
public class WorkflowRuntimeStoreTests
{
    private readonly WorkflowsPostgresFixture _fixture;

    public WorkflowRuntimeStoreTests(WorkflowsPostgresFixture fixture)
    {
        _fixture = fixture;
    }

    private static WorkflowRuntimeStore Store(WorkflowsDbContext db) =>
        new(db, new RuntimeSelfInfoProvider(new ConfigurationBuilder().Build()));

    private static string Tenant() => "t" + Guid.NewGuid().ToString("N")[..12];

    private static string Sha256(string raw) =>
        Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(raw))).ToLowerInvariant();

    [Fact]
    public async Task List_seeds_one_platform_runtime_per_tenant()
    {
        var tenantId = Tenant();
        await using var db = _fixture.CreateContext();
        var store = Store(db);

        var first = await store.ListAsync(tenantId);
        var platform = Assert.Single(first);
        Assert.Equal(WorkflowRuntimeKind.Platform, platform.Kind);
        Assert.Equal(WorkflowRuntimeStatus.Online, platform.Status);
        Assert.False(platform.IsDefault); // platform is the implicit fallback, not a "default" self-hosted runtime
        Assert.NotNull(platform.InfoJson);

        // Idempotent: listing again must NOT create a second platform runtime.
        var second = await store.ListAsync(tenantId);
        var platformAgain = Assert.Single(second);
        Assert.Equal(platform.Id, platformAgain.Id);
    }

    [Fact]
    public async Task Platform_runtime_is_isolated_per_tenant()
    {
        var tenantA = Tenant();
        var tenantB = Tenant();
        await using var db = _fixture.CreateContext();
        var store = Store(db);

        var a = await store.ListAsync(tenantA);
        var b = await store.ListAsync(tenantB);

        var platformA = Assert.Single(a);
        var platformB = Assert.Single(b);
        Assert.NotEqual(platformA.Id, platformB.Id);

        // Tenant A must never see tenant B's runtimes.
        await store.CreateInboundAsync(tenantB, "B engine", "https://b.example.com", "secret-b");
        var aAfter = await store.ListAsync(tenantA);
        Assert.Single(aAfter);
    }

    [Fact]
    public async Task CreateInboundAsync_hashes_key_and_sets_default_on_first()
    {
        var tenantId = Tenant();
        await using var db = _fixture.CreateContext();
        var store = Store(db);

        var first = await store.CreateInboundAsync(tenantId, "my-server", "https://wf.example.com/", "raw-key");
        Assert.Equal(WorkflowRuntimeKind.SelfHosted, first.Kind);
        Assert.Equal("https://wf.example.com", first.Endpoint); // trailing slash trimmed
        Assert.True(first.IsDefault);
        Assert.NotNull(first.ApiKeyHash);
        Assert.NotEqual("raw-key", first.ApiKeyHash);
        Assert.Equal(Sha256("raw-key"), first.ApiKeyHash);

        // Second self-hosted runtime is not default.
        var second = await store.CreateInboundAsync(tenantId, "second", "https://wf2.example.com", null);
        Assert.False(second.IsDefault);
        Assert.Null(second.ApiKeyHash);
    }

    [Fact]
    public async Task CreateInboundAsync_rejects_invalid_endpoint()
    {
        var tenantId = Tenant();
        await using var db = _fixture.CreateContext();
        var store = Store(db);

        await Assert.ThrowsAsync<ArgumentException>(
            () => store.CreateInboundAsync(tenantId, "bad", "not-a-url", null));
        await Assert.ThrowsAsync<ArgumentException>(
            () => store.CreateInboundAsync(tenantId, "bad", "ftp://example.com", null));
    }

    [Fact]
    public async Task DeleteAsync_removes_self_hosted_and_reassigns_default()
    {
        var tenantId = Tenant();
        await using var db = _fixture.CreateContext();
        var store = Store(db);

        var first = await store.CreateInboundAsync(tenantId, "first", "https://a.example.com", null);
        var second = await store.CreateInboundAsync(tenantId, "second", "https://b.example.com", null);
        Assert.True(first.IsDefault);
        Assert.False(second.IsDefault);

        // Deleting the default reassigns it to the remaining self-hosted runtime.
        Assert.True(await store.DeleteAsync(tenantId, first.Id));
        var remaining = await store.GetAsync(tenantId, second.Id);
        Assert.NotNull(remaining);
        Assert.True(remaining!.IsDefault);
    }

    [Fact]
    public async Task CreateInboundAsync_is_idempotent_per_endpoint()
    {
        var tenantId = Tenant();
        await using var db = _fixture.CreateContext();
        var store = Store(db);

        var first = await store.CreateInboundAsync(tenantId, "first", "https://wf.example.com/", "key");
        var second = await store.CreateInboundAsync(tenantId, "second", "https://wf.example.com", "other");

        // Same normalized endpoint → same row, no duplicate.
        Assert.Equal(first.Id, second.Id);

        var all = await store.ListAsync(tenantId);
        Assert.Equal(2, all.Count); // platform + the single self-hosted runtime
        Assert.Single(all, r => r.Kind == WorkflowRuntimeKind.SelfHosted);
    }

    [Fact]
    public async Task DeleteAsync_never_deletes_platform_runtime()
    {
        var tenantId = Tenant();
        await using var db = _fixture.CreateContext();
        var store = Store(db);

        var runtimes = await store.ListAsync(tenantId);
        var platform = Assert.Single(runtimes);

        await Assert.ThrowsAsync<InvalidOperationException>(
            () => store.DeleteAsync(tenantId, platform.Id));

        // Platform is still there.
        var after = await store.ListAsync(tenantId);
        Assert.Single(after);
    }
}