using Xunit;

namespace Admin.NET.Plugin.AiDOP.Tests.ApprovalFlow;

/// <summary>
/// S7 成品检验单（<c>S7_FQC_INSPBILL</c>，源 qms_qcpp_inspbill）通用审批旁路封堵 · 源码契约测试（S7-FQC-GUARD-1）。
///
/// 背景：守卫名单此前只有 S5_IQC_INSPBILL / S6_PROCESS_INSPECTION / IPQC_INSPECTION，
/// S7 一直在名单外（早前批次显式记为 OUT OF SCOPE）。
///
/// 为什么 S7 的绕过面是**全部**业务语义：本链的 <see cref="FqcInspBillFlowBizHandler"/> 三个回调
/// （OnFlowStarted / OnNodeCompleted / OnFlowCompleted）**全是 no-op**，
/// 业务写入一律由 <c>FqcInspBillFlowService</c> 在引擎之外、同事务内完成。于是通用审批：
///   ① N1 approve → submit-result 从未写 pd/hgsl/bhgsl/clfs 就推到 N2；更严重的是 GW_RESULT
///      网关按 pd 算 disposition_required，pd 为 null 时算 0 → 不合格单静默绕过 N3 QE 处置直接结束；
///   ② N2 approve → 跳过 TryEnqueueFqcPassOutboxAsync，合格出站 Outbox 永不入队；
///   ③ N2 reject → FlowEngine.Reject 把实例置 Rejected 终态并取消所有待办，而专用 supervisor-reject
///      是 ReturnToPrev 回 N1 + 同事务复位 qms_fqcbj.FINSPECTSTATUS + 同步 mdp_std_fqc_task；
///   ④ N3 approve → 推到 end 而 ado_s7_fqc_qe_disposition 永不写入，处置轨迹为空且无法补记。
///
/// 沿用本仓既有做法——源码契约断言而非行为级集成测试：FlowTaskService 依赖
/// SqlSugarRepository&lt;T&gt;，裸 xUnit 进程无法实例化。真实阻断由本批 Runtime R1–R4 覆盖。
/// </summary>
public class S7FqcGenericApprovalGuardContractTests
{
    private const string BizType = "S7_FQC_INSPBILL";
    private const string Guard = "EnsureDedicatedEntryOnlyAsync";

    private static string FlowTaskService() => File.ReadAllText(FindFile(
        "server", "Plugins", "Admin.NET.Plugin.ApprovalFlow", "Service", "FlowTask", "FlowTaskService.cs"));

    private static string FlowConst() => File.ReadAllText(FindFile(
        "server", "Plugins", "Admin.NET.Plugin.AiDOP", "FinishedWarehouse", "FqcInspBillFlowBizHandler.cs"));

    private static string FlowService() => File.ReadAllText(FindFile(
        "server", "Plugins", "Admin.NET.Plugin.AiDOP", "FinishedWarehouse", "FqcInspBillFlowService.cs"));

    private static string Dict() => Slice(FlowTaskService(), "DedicatedEntryOnlyBizTypes = new()", "};");

    // ── 纳入守卫 ──

    /// <summary>S7 真实 BizType 必须在名单里，且与常量定义一致（不允许两处写不同字面量）。</summary>
    [Fact]
    public void S7BizType_IsInDedicatedEntryGuard()
    {
        Assert.Contains($"[\"{BizType}\"]", Dict());
        Assert.Contains($"public const string BizType = \"{BizType}\"", FlowConst());
    }

    /// <summary>§15 Regression Freeze：新增 S7 不得挤掉既有三条。</summary>
    [Theory]
    [InlineData("S5_IQC_INSPBILL")]
    [InlineData("S6_PROCESS_INSPECTION")]
    [InlineData("IPQC_INSPECTION")]
    public void ExistingGuardedBizTypes_ArePreserved(string bizType)
    {
        Assert.Contains($"[\"{bizType}\"]", Dict());
    }

    /// <summary>名单恰好四条 —— 防止本批顺手扩大守卫范围。</summary>
    [Fact]
    public void Guard_CoversExactlyFourBizTypes()
    {
        Assert.Equal(4, CountOf(Dict(), "\"] = \""));
    }

    // ── 四个通用入口全覆盖（§14）──

    /// <summary>approve / reject / batchApprove / batchReject 四个入口都必须先过同一守卫。</summary>
    [Theory]
    [InlineData("_engine.Approve(input.TaskId, input.Comment)")]
    [InlineData("_engine.Reject(input.TaskId, input.Comment)")]
    public void SingleActions_GuardPrecedesEngineCall(string engineCall)
    {
        var s = FlowTaskService();
        var at = s.IndexOf(engineCall, StringComparison.Ordinal);
        Assert.True(at > 0, $"未找到引擎调用点：{engineCall}");
        Assert.True(s.LastIndexOf(Guard + "(", at, StringComparison.Ordinal) > 0,
            $"引擎调用 {engineCall} 之前缺少 {Guard} 守卫");
    }

    /// <summary>
    /// 批量入口的循环体各自持有守卫。批量端点不会走单项方法体，
    /// 少一处就等于批量仍可绕过（§21 / §22）。
    /// </summary>
    [Fact]
    public void BatchActions_EachLoopBodyCallsGuard()
    {
        var s = FlowTaskService();
        Assert.Equal(4, CountOf(s, Guard + "(taskId)") + CountOf(s, Guard + "(input.TaskId)"));
        foreach (var batch in new[] { "BatchApprove", "BatchReject" })
        {
            var body = Slice(s, $"public async Task<BatchActionResult> {batch}(", "return result;");
            Assert.Contains(Guard + "(taskId)", body);
        }
    }

    // ── §11 Guard 必须早于任何 mutation ──

    /// <summary>守卫是动作方法的第一条语句，因此 fail 时任务状态/实例/日志/下一节点都还没动。</summary>
    [Theory]
    [InlineData("public async Task Approve(TaskActionInput input)")]
    [InlineData("public async Task Reject(TaskActionInput input)")]
    public void Guard_IsFirstStatementOfAction(string signature)
    {
        var body = Slice(FlowTaskService(), signature, "}");
        var lines = body.Split('\n').Select(l => l.Trim()).Where(l => l != "" && l != "{" && !l.StartsWith("//", StringComparison.Ordinal)).ToList();
        var first = lines.FirstOrDefault(l => !l.StartsWith("public ", StringComparison.Ordinal));
        Assert.Equal($"await {Guard}(input.TaskId);", first);
    }

    /// <summary>守卫自身只读不写：不得在判定过程里改任何实体。</summary>
    [Fact]
    public void Guard_PerformsNoMutation()
    {
        var guard = Slice(FlowTaskService(), $"private async Task {Guard}(long taskId)", "}\n\n    /// <summary>");
        foreach (var write in new[] { "AsUpdateable", "InsertAsync", "DeleteAsync", "ExecuteCommandAsync", "UseTranAsync" })
            Assert.DoesNotContain(write, guard);
    }

    // ── §10 精确匹配 ──

    /// <summary>必须是精确字典查表，禁止 Contains / StartsWith 之类模糊匹配。</summary>
    [Fact]
    public void Guard_UsesExactDictionaryLookup()
    {
        var guard = Slice(FlowTaskService(), $"private async Task {Guard}(long taskId)", "}\n\n    /// <summary>");
        Assert.Contains("DedicatedEntryOnlyBizTypes.TryGetValue(instance.BizType, out var hint)", guard);
        foreach (var fuzzy in new[] { ".Contains(", ".StartsWith(", ".EndsWith(", "ToUpper", "ToLower" })
            Assert.DoesNotContain(fuzzy, guard);
    }

    /// <summary>§16 Control：明确允许通用审批的 BizType 不得被纳入。</summary>
    [Theory]
    [InlineData("CONTRACT_REVIEW")]
    [InlineData("ORDER_REVIEW")]
    [InlineData("SMART_OPS_IMPROVEMENT")]
    [InlineData("EXCEPTION_REPORT")]
    [InlineData("MATERIAL_SHORTAGE")]
    public void Guard_DoesNotBlockGenericApprovalBizTypes(string bizType)
    {
        Assert.DoesNotContain(bizType, Dict());
    }

    /// <summary>§9 禁止散落 if：不得在四个动作里各写一遍 S7 的判断。</summary>
    [Fact]
    public void NoScatteredPerBizTypeIfStatements()
    {
        var s = FlowTaskService();
        // BizType 字面量只应出现在名单里（1 次），不应出现在任何 if 条件中
        Assert.Equal(1, CountOf(s, $"\"{BizType}\""));
        Assert.DoesNotContain($"== \"{BizType}\"", s);
    }

    // ── §12 权威来源与不泄漏 ──

    /// <summary>权威 BizType 必须从库中 instance 反查，不得取自请求体（否则可伪造绕过）。</summary>
    [Fact]
    public void Guard_ReadsBizTypeFromDatabase()
    {
        var guard = Slice(FlowTaskService(), $"private async Task {Guard}(long taskId)", "}\n\n    /// <summary>");
        Assert.Contains("_taskRep.GetByIdAsync(taskId)", guard);
        Assert.Contains("_instanceRep.GetByIdAsync(task.InstanceId)", guard);
        Assert.DoesNotContain("input.BizType", guard);
    }

    /// <summary>§13 对外文案不得泄漏 RoleId / TenantId / 流程定义 Id 等内部实现。</summary>
    [Fact]
    public void GuardMessage_DoesNotLeakInternals()
    {
        var dict = Dict();
        foreach (var leak in new[] { "TenantId", "RoleId", "FlowId", "DefinitionId", "InstanceId" })
            Assert.DoesNotContain($"{leak}=", dict);
    }

    /// <summary>文案必须指向专用业务页，且不是裸技术异常。</summary>
    [Fact]
    public void GuardMessage_PointsToDedicatedPage()
    {
        var line = Dict().Split('\n').Single(l => l.Contains($"[\"{BizType}\"]", StringComparison.Ordinal));
        Assert.Contains("FQC检验单详情", line);
        Assert.Contains("不支持在审批中心直接同意/拒绝", line);
        foreach (var bad in new[] { "BizType not allowed", "NullReference", "500" })
            Assert.DoesNotContain(bad, line);
    }

    // ── 封堵的前提：专用入口必须仍然存在且直调引擎 ──

    /// <summary>四个专用入口都必须在（否则封堵等于封死业务）。</summary>
    [Theory]
    [InlineData("submit-result")]
    [InlineData("supervisor-approve")]
    [InlineData("supervisor-reject")]
    [InlineData("qe-submit-disposition")]
    public void DedicatedEntries_StillExist(string route)
    {
        Assert.Contains($"[HttpPost(\"{route}\")]", FlowService());
    }

    /// <summary>专用入口直调 FlowEngine，不经 FlowTaskService —— 故守卫不会误伤正常业务路径。</summary>
    [Fact]
    public void DedicatedEntries_CallEngineDirectly_NotViaFlowTaskService()
    {
        var s = FlowService();
        Assert.Contains("_flowEngine.Approve(", s);
        Assert.Contains("_flowEngine.ReturnToPrev(", s);
        Assert.DoesNotContain("FlowTaskService", s);
        Assert.DoesNotContain("flowTask/approve", s);
    }

    /// <summary>
    /// 冻结"为什么必须封堵"的两条根据：
    /// ① Handler 回调全 no-op（业务副作用不在引擎里）；② 专用 reject 走 ReturnToPrev 而非置终态。
    /// 任一条将来被改动，本守卫的理由需要重新评估，测试在此提醒。
    /// </summary>
    [Fact]
    public void BypassRationale_HandlerCallbacksAreNoOp()
    {
        var h = FlowConst();
        foreach (var cb in new[] { "OnFlowStarted", "OnNodeCompleted", "OnFlowCompleted" })
        {
            var line = h.Split('\n').Single(l => l.Contains($"public Task {cb}(", StringComparison.Ordinal));
            Assert.Contains("Task.CompletedTask", line);
        }
    }

    /// <summary>专用 supervisor-reject 的业务副作用必须仍在（它们正是通用 Reject 绕过的东西）。</summary>
    [Fact]
    public void BypassRationale_DedicatedRejectHasBusinessSideEffects()
    {
        var body = Slice(FlowService(), "public async Task<FqcFlowStateOutput> SupervisorReject(", "public async Task<FqcFlowStateOutput> QeSubmitDisposition(");
        Assert.Contains("退回必须填写意见", body);
        Assert.Contains("_flowEngine.ReturnToPrev(", body);
        Assert.Contains("UPDATE qms_fqcbj SET FINSPECTSTATUS", body);
        Assert.Contains("SyncBillToStdSafeAsync", body);
    }

    private static int CountOf(string src, string needle)
    {
        int n = 0, i = 0;
        while ((i = src.IndexOf(needle, i, StringComparison.Ordinal)) >= 0) { n++; i += needle.Length; }
        return n;
    }

    private static string Slice(string src, string from, string to)
    {
        var a = src.IndexOf(from, StringComparison.Ordinal);
        Assert.True(a >= 0, $"未找到起点：{from}");
        var b = src.IndexOf(to, a + from.Length, StringComparison.Ordinal);
        return b > a ? src[a..b] : src[a..];
    }

    private static string FindFile(params string[] parts)
    {
        var dir = new DirectoryInfo(AppContext.BaseDirectory);
        while (dir != null)
        {
            var candidate = Path.Combine(new[] { dir.FullName }.Concat(parts).ToArray());
            if (File.Exists(candidate)) return candidate;
            dir = dir.Parent;
        }
        throw new FileNotFoundException(string.Join("/", parts));
    }
}