using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Logging.Abstractions;
using ScadaLink.SiteRuntime.Persistence;

namespace ScadaLink.SiteRuntime.Tests.Persistence;

/// <summary>
/// Tests for SiteStorageService using file-based SQLite (temp files).
/// Validates the schema, CRUD operations, and constraint behavior.
/// </summary>
public class SiteStorageServiceTests : IAsyncLifetime, IDisposable
{
    private readonly string _dbFile;
    private SiteStorageService _storage = null!;

    public SiteStorageServiceTests()
    {
        _dbFile = Path.Combine(Path.GetTempPath(), $"site-storage-test-{Guid.NewGuid():N}.db");
    }

    public async Task InitializeAsync()
    {
        _storage = new SiteStorageService(
            $"Data Source={_dbFile}",
            NullLogger<SiteStorageService>.Instance);
        await _storage.InitializeAsync();
    }

    public Task DisposeAsync() => Task.CompletedTask;

    public void Dispose()
    {
        try { File.Delete(_dbFile); } catch { /* cleanup */ }
    }

    [Fact]
    public async Task InitializeAsync_CreatesTablesWithoutError()
    {
        // Already called in InitializeAsync — just verify no exception
        // Call again to verify idempotency (CREATE IF NOT EXISTS)
        await _storage.InitializeAsync();
    }

    [Fact]
    public async Task StoreAndRetrieve_DeployedConfig_RoundTrips()
    {
        await _storage.StoreDeployedConfigAsync(
            "Pump1", "{\"test\":true}", "dep-001", "sha256:abc", isEnabled: true);

        var configs = await _storage.GetAllDeployedConfigsAsync();

        Assert.Single(configs);
        Assert.Equal("Pump1", configs[0].InstanceUniqueName);
        Assert.Equal("{\"test\":true}", configs[0].ConfigJson);
        Assert.Equal("dep-001", configs[0].DeploymentId);
        Assert.Equal("sha256:abc", configs[0].RevisionHash);
        Assert.True(configs[0].IsEnabled);
    }

    [Fact]
    public async Task StoreDeployedConfig_Upserts_OnConflict()
    {
        await _storage.StoreDeployedConfigAsync(
            "Pump1", "{\"v\":1}", "dep-001", "sha256:aaa", isEnabled: true);
        await _storage.StoreDeployedConfigAsync(
            "Pump1", "{\"v\":2}", "dep-002", "sha256:bbb", isEnabled: false);

        var configs = await _storage.GetAllDeployedConfigsAsync();

        Assert.Single(configs);
        Assert.Equal("{\"v\":2}", configs[0].ConfigJson);
        Assert.Equal("dep-002", configs[0].DeploymentId);
        Assert.False(configs[0].IsEnabled);
    }

    [Fact]
    public async Task RemoveDeployedConfig_RemovesConfigAndOverrides()
    {
        await _storage.StoreDeployedConfigAsync(
            "Pump1", "{}", "dep-001", "sha256:aaa", isEnabled: true);
        await _storage.SetStaticOverrideAsync("Pump1", "Temperature", "100");

        await _storage.RemoveDeployedConfigAsync("Pump1");

        var configs = await _storage.GetAllDeployedConfigsAsync();
        var overrides = await _storage.GetStaticOverridesAsync("Pump1");

        Assert.Empty(configs);
        Assert.Empty(overrides);
    }

    [Fact]
    public async Task SetInstanceEnabled_UpdatesFlag()
    {
        await _storage.StoreDeployedConfigAsync(
            "Pump1", "{}", "dep-001", "sha256:aaa", isEnabled: true);

        await _storage.SetInstanceEnabledAsync("Pump1", false);

        var configs = await _storage.GetAllDeployedConfigsAsync();
        Assert.False(configs[0].IsEnabled);

        await _storage.SetInstanceEnabledAsync("Pump1", true);

        configs = await _storage.GetAllDeployedConfigsAsync();
        Assert.True(configs[0].IsEnabled);
    }

    [Fact]
    public async Task SetInstanceEnabled_NonExistent_DoesNotThrow()
    {
        // Should not throw for a missing instance
        await _storage.SetInstanceEnabledAsync("DoesNotExist", true);
    }

    // ── Static Override Tests ──

    [Fact]
    public async Task SetAndGetStaticOverride_RoundTrips()
    {
        await _storage.SetStaticOverrideAsync("Pump1", "Temperature", "98.6");

        var overrides = await _storage.GetStaticOverridesAsync("Pump1");

        Assert.Single(overrides);
        Assert.Equal("98.6", overrides["Temperature"]);
    }

    [Fact]
    public async Task SetStaticOverride_Upserts_OnConflict()
    {
        await _storage.SetStaticOverrideAsync("Pump1", "Temperature", "98.6");
        await _storage.SetStaticOverrideAsync("Pump1", "Temperature", "100.0");

        var overrides = await _storage.GetStaticOverridesAsync("Pump1");

        Assert.Single(overrides);
        Assert.Equal("100.0", overrides["Temperature"]);
    }

    [Fact]
    public async Task ClearStaticOverrides_RemovesAll()
    {
        await _storage.SetStaticOverrideAsync("Pump1", "Temperature", "98.6");
        await _storage.SetStaticOverrideAsync("Pump1", "Pressure", "50.0");

        await _storage.ClearStaticOverridesAsync("Pump1");

        var overrides = await _storage.GetStaticOverridesAsync("Pump1");
        Assert.Empty(overrides);
    }

    [Fact]
    public async Task GetStaticOverrides_IsolatedPerInstance()
    {
        await _storage.SetStaticOverrideAsync("Pump1", "Temperature", "98.6");
        await _storage.SetStaticOverrideAsync("Pump2", "Pressure", "50.0");

        var pump1 = await _storage.GetStaticOverridesAsync("Pump1");
        var pump2 = await _storage.GetStaticOverridesAsync("Pump2");

        Assert.Single(pump1);
        Assert.Single(pump2);
        Assert.True(pump1.ContainsKey("Temperature"));
        Assert.True(pump2.ContainsKey("Pressure"));
    }

    [Fact]
    public async Task MultipleInstances_IndependentLifecycle()
    {
        await _storage.StoreDeployedConfigAsync("Pump1", "{}", "d1", "h1", true);
        await _storage.StoreDeployedConfigAsync("Pump2", "{}", "d2", "h2", true);
        await _storage.StoreDeployedConfigAsync("Pump3", "{}", "d3", "h3", false);

        var configs = await _storage.GetAllDeployedConfigsAsync();
        Assert.Equal(3, configs.Count);

        await _storage.RemoveDeployedConfigAsync("Pump2");

        configs = await _storage.GetAllDeployedConfigsAsync();
        Assert.Equal(2, configs.Count);
        Assert.DoesNotContain(configs, c => c.InstanceUniqueName == "Pump2");
    }

    // ── Negative Tests ──

    [Fact]
    public async Task Schema_DoesNotContain_AlarmStateTable()
    {
        // Per design: no alarm state table in site SQLite
        var configs = await _storage.GetAllDeployedConfigsAsync();
        var overrides = await _storage.GetStaticOverridesAsync("nonexistent");

        Assert.Empty(configs);
        Assert.Empty(overrides);
    }
}
