using System.Collections.Generic;
using System.Reflection;
using AxCopilot.Models;
using AxCopilot.Services;
using AxCopilot.Services.Agent;
using FluentAssertions;
using Xunit;

namespace AxCopilot.Tests.Services;

public class LlmRuntimeOverrideTests
{
    [Fact]
    public void PushInferenceOverride_PopInferenceOverride_RestoresPreviousState()
    {
        var settings = new SettingsService();
        settings.Settings.Llm.Service = "ollama";
        settings.Settings.Llm.Model = "base-model";
        settings.Settings.Llm.Temperature = 0.7;

        using var llm = new LlmService(settings);

        llm.PushRouteOverride("gemini", "gemini-2.5-pro");
        llm.PushInferenceOverride(temperature: 0.2, reasoningEffort: "high");

        llm.GetCurrentModelInfo().service.Should().Be("gemini");
        llm.GetCurrentModelInfo().model.Should().Be("gemini-2.5-pro");
        InvokePrivate<double>(llm, "ResolveTemperature").Should().Be(0.2);
        InvokePrivate<string?>(llm, "ResolveReasoningEffort").Should().Be("high");

        llm.PopInferenceOverride();
        llm.GetCurrentModelInfo().service.Should().Be("gemini");
        llm.GetCurrentModelInfo().model.Should().Be("gemini-2.5-pro");
        InvokePrivate<double>(llm, "ResolveTemperature").Should().Be(0.7);
        InvokePrivate<string?>(llm, "ResolveReasoningEffort").Should().BeNull();

        llm.ClearRouteOverride();
        llm.GetCurrentModelInfo().service.Should().Be("ollama");
        llm.GetCurrentModelInfo().model.Should().Be("base-model");
    }

    [Fact]
    public void AgentLoop_ResolveSkillRuntimeOverrides_MapsModelAndEffort()
    {
        var settings = new SettingsService();
        settings.Settings.Llm.Service = "ollama";
        settings.Settings.Llm.Model = "base-model";
        settings.Settings.Llm.RegisteredModels =
        [
            new RegisteredModel
            {
                Alias = "gpt-5.4",
                EncryptedModelName = "gpt-5.4",
                Service = "vllm",
            }
        ];

        using var llm = new LlmService(settings);
        var loop = new AgentLoopService(llm, ToolRegistry.CreateDefault(), settings);
        var messages = new List<ChatMessage>
        {
            new()
            {
                Role = "system",
                Content = """
                          [Skill Runtime Policy]
                          - preferred_model: gpt-5.4
                          - reasoning_effort: high
                          - execution_context: fork
                          - allowed_tools: Read, process
                          - hook_names: lint-pre, verify-post
                          - hook_filters: lint-pre@pre@file_edit, verify-post@post@*
                          """
            },
            new() { Role = "user", Content = "test" }
        };

        var method = typeof(AgentLoopService).GetMethod(
            "ResolveSkillRuntimeOverrides",
            BindingFlags.NonPublic | BindingFlags.Instance);
        method.Should().NotBeNull();

        var result = method!.Invoke(loop, [messages]);
        result.Should().NotBeNull();

        var resultType = result!.GetType();
        resultType.GetProperty("Service")!.GetValue(result)!.Should().Be("vllm");
        resultType.GetProperty("Model")!.GetValue(result)!.Should().Be("gpt-5.4");
        resultType.GetProperty("ReasoningEffort")!.GetValue(result)!.Should().Be("high");
        resultType.GetProperty("Temperature")!.GetValue(result)!.Should().Be(0.2);
        resultType.GetProperty("RequireForkExecution")!.GetValue(result)!.Should().Be(true);

        var allowedSet = (IReadOnlySet<string>)resultType.GetProperty("AllowedToolNames")!.GetValue(result)!;
        allowedSet.Should().Contain("file_read");
        allowedSet.Should().Contain("process");

        var hookSet = (IReadOnlySet<string>)resultType.GetProperty("HookNames")!.GetValue(result)!;
        hookSet.Should().Contain("lint-pre");
        hookSet.Should().Contain("verify-post");

        var filters = (IReadOnlyList<object>)resultType.GetProperty("HookFilters")!.GetValue(result)!;
        filters.Should().NotBeEmpty();
    }

    private static T InvokePrivate<T>(object instance, string methodName)
    {
        var method = instance.GetType().GetMethod(methodName, BindingFlags.NonPublic | BindingFlags.Instance);
        method.Should().NotBeNull();
        return (T)method!.Invoke(instance, null)!;
    }

    [Fact]
    public void ResolveServerInfo_VllmGlobalInsecureTls_ShouldBeApplied()
    {
        var settings = new SettingsService();
        settings.Settings.Llm.Service = "vllm";
        settings.Settings.Llm.Model = "vllm-model";
        settings.Settings.Llm.VllmEndpoint = "https://vllm.internal";
        settings.Settings.Llm.VllmApiKey = "global-key";
        settings.Settings.Llm.VllmAllowInsecureTls = true;
        settings.Settings.Llm.EncryptionEnabled = false;

        using var llm = new LlmService(settings);

        var method = typeof(LlmService).GetMethod("ResolveServerInfo", BindingFlags.NonPublic | BindingFlags.Instance);
        method.Should().NotBeNull();

        var tuple = ((string Endpoint, string ApiKey, bool AllowInsecureTls))method!.Invoke(llm, null)!;
        tuple.Endpoint.Should().Be("https://vllm.internal");
        tuple.ApiKey.Should().Be("global-key");
        tuple.AllowInsecureTls.Should().Be(true);
    }

    [Fact]
    public void ResolveServerInfo_RegisteredModelOverride_ShouldUseEndpointAndApiKey()
    {
        var settings = new SettingsService();
        settings.Settings.Llm.Service = "vllm";
        settings.Settings.Llm.Model = "corp-vllm-model";
        settings.Settings.Llm.VllmEndpoint = "https://fallback.internal";
        settings.Settings.Llm.VllmApiKey = "fallback-key";
        settings.Settings.Llm.VllmAllowInsecureTls = false;
        settings.Settings.Llm.EncryptionEnabled = false;
        settings.Settings.Llm.RegisteredModels =
        [
            new RegisteredModel
            {
                Alias = "corp",
                EncryptedModelName = "corp-vllm-model",
                Service = "vllm",
                Endpoint = "https://model.internal",
                ApiKey = "model-key",
                AllowInsecureTls = true
            }
        ];

        using var llm = new LlmService(settings);

        var method = typeof(LlmService).GetMethod("ResolveServerInfo", BindingFlags.NonPublic | BindingFlags.Instance);
        method.Should().NotBeNull();

        var tuple = ((string Endpoint, string ApiKey, bool AllowInsecureTls))method!.Invoke(llm, null)!;
        tuple.Endpoint.Should().Be("https://model.internal");
        tuple.ApiKey.Should().Be("model-key");
        tuple.AllowInsecureTls.Should().Be(true);
    }

    [Fact]
    public void ResolveServerInfo_VllmEncryptedApiKey_ShouldBeDecryptedAtRuntime()
    {
        var settings = new SettingsService();
        settings.Settings.Llm.Service = "vllm";
        settings.Settings.Llm.Model = "corp-vllm-model";
        settings.Settings.Llm.VllmEndpoint = "https://secure.internal";
        settings.Settings.Llm.EncryptionEnabled = true;
        settings.Settings.Llm.VllmApiKey = CryptoService.EncryptIfEnabled("enc-key-value", true);

        using var llm = new LlmService(settings);

        var method = typeof(LlmService).GetMethod("ResolveServerInfo", BindingFlags.NonPublic | BindingFlags.Instance);
        method.Should().NotBeNull();

        var tuple = ((string Endpoint, string ApiKey, bool AllowInsecureTls))method!.Invoke(llm, null)!;
        tuple.Endpoint.Should().Be("https://secure.internal");
        tuple.ApiKey.Should().Be("enc-key-value");
    }

    [Fact]
    public void ResolveServerInfo_RegisteredModelInsecureFalse_GlobalInsecureTrue_ShouldRemainTrue()
    {
        var settings = new SettingsService();
        settings.Settings.Llm.Service = "vllm";
        settings.Settings.Llm.Model = "corp-vllm-model";
        settings.Settings.Llm.VllmEndpoint = "https://fallback.internal";
        settings.Settings.Llm.VllmApiKey = "fallback-key";
        settings.Settings.Llm.VllmAllowInsecureTls = true;
        settings.Settings.Llm.EncryptionEnabled = false;
        settings.Settings.Llm.RegisteredModels =
        [
            new RegisteredModel
            {
                Alias = "corp",
                EncryptedModelName = "corp-vllm-model",
                Service = "vllm",
                Endpoint = "https://model.internal",
                ApiKey = "model-key",
                AllowInsecureTls = false
            }
        ];

        using var llm = new LlmService(settings);
        var method = typeof(LlmService).GetMethod("ResolveServerInfo", BindingFlags.NonPublic | BindingFlags.Instance);
        method.Should().NotBeNull();

        var tuple = ((string Endpoint, string ApiKey, bool AllowInsecureTls))method!.Invoke(llm, null)!;
        tuple.AllowInsecureTls.Should().BeTrue();
    }

    [Fact]
    public void GetRuntimeConnectionSnapshot_Vllm_ShouldExposeMaskedRuntimeInputs()
    {
        var settings = new SettingsService();
        settings.Settings.Llm.Service = "vllm";
        settings.Settings.Llm.Model = "corp-vllm-model";
        settings.Settings.Llm.VllmEndpoint = "https://model.internal:8443";
        settings.Settings.Llm.VllmApiKey = "model-key";
        settings.Settings.Llm.VllmAllowInsecureTls = true;
        settings.Settings.Llm.EncryptionEnabled = false;

        using var llm = new LlmService(settings);
        var snapshot = llm.GetRuntimeConnectionSnapshot();

        snapshot.Service.Should().Be("vllm");
        snapshot.Model.Should().Be("corp-vllm-model");
        snapshot.Endpoint.Should().Be("https://model.internal:8443");
        snapshot.AllowInsecureTls.Should().BeTrue();
        snapshot.HasApiKey.Should().BeTrue();
    }

    [Fact]
    public void GetRuntimeConnectionSnapshot_OllamaWithoutKey_ShouldReportNoKey()
    {
        var settings = new SettingsService();
        settings.Settings.Llm.Service = "ollama";
        settings.Settings.Llm.Model = "qwen2.5-coder";
        settings.Settings.Llm.OllamaEndpoint = "http://localhost:11434";
        settings.Settings.Llm.OllamaApiKey = "";
        settings.Settings.Llm.EncryptionEnabled = false;

        using var llm = new LlmService(settings);
        var snapshot = llm.GetRuntimeConnectionSnapshot();

        snapshot.Service.Should().Be("ollama");
        snapshot.Model.Should().Be("qwen2.5-coder");
        snapshot.Endpoint.Should().Be("http://localhost:11434");
        snapshot.AllowInsecureTls.Should().BeFalse();
        snapshot.HasApiKey.Should().BeFalse();
    }
}