using System.Text.Json;
using System.Text.Json.Nodes;
using Admin.NET.Plugin.AiDOP.Service.S6;
using Xunit;

namespace Admin.NET.Plugin.AiDOP.Tests.S6.Manufacturing;

/// <summary>
/// S6-LEGACY-SNAPSHOT-MIGRATION-1 契约测试：存量运行中实例的审批权威快照迁移。
///
/// <para>两层覆盖：</para>
/// <list type="number">
///   <item><b>行为级</b>——<c>ParseNumericRoleRefs</c> / <c>RewriteAuthority</c> 是纯静态方法，
///         不依赖 DB，可直接喂真实形状的 FlowJson 断言。快照解析与改写是本批最容易悄悄改坏的地方
///         （approverType 语义、token 顺序、只动 approverIds），必须真跑。</item>
///   <item><b>源码契约级</b>——安全谓词（ACTIVE 判据、租户反查、跨租户限定、目标角色唯一性与成员门禁、
///         回滚来源门禁、并发守卫、留证同事务、append-only、批次边界）依赖
///         <c>ISqlSugarClient</c>，裸 xUnit 进程无法实例化（见 S8ExceptionFlowTenantContextContractTests），
///         故按本仓既有惯例做源码断言；真实数据行为由本批 Runtime R1–R10 覆盖。</item>
/// </list>
/// </summary>
public class S6LegacyFlowAuthorityMigrationContractTests
{
    private static string Svc() => File.ReadAllText(FindFile(
        "server", "Plugins", "Admin.NET.Plugin.AiDOP", "Service", "S6", "S6LegacyFlowAuthorityMigrationService.cs"));

    private static string Entity() => File.ReadAllText(FindFile(
        "server", "Plugins", "Admin.NET.Plugin.AiDOP", "Entity", "S6", "AdoS6FlowAuthorityMigrationLog.cs"));

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

    /// <summary>与真实快照同形：N1=Initiator、N2/N3=Role 数字、另含 SpecificUser / Department 干扰节点。</summary>
    private static string SampleSnapshot(string n2Ids = "1329916010002", string n3Ids = "1329916010003") => JsonSerializer.Serialize(new
    {
        nodes = new object[]
        {
            new { id = "start", type = "bpmn:startEvent", properties = new { nodeName = "开始" } },
            new { id = "N1_SUBMIT", type = "bpmn:userTask", properties = new { nodeName = "提交审核", approverType = "Initiator", approverIds = "", approverNames = "发起人" } },
            new { id = "N2_SUP_REVIEW", type = "bpmn:userTask", properties = new { nodeName = "检验主管审核", approverType = "Role", approverIds = n2Ids, approverNames = "过程检验主管" } },
            new { id = "GW_RESULT", type = "bpmn:exclusiveGateway", properties = new { nodeName = "质量结果分流" } },
            new { id = "N3_QE_DISPOSITION", type = "bpmn:userTask", properties = new { nodeName = "质量处置", approverType = "Role", approverIds = n3Ids, approverNames = "过程检验质量工程师" } },
            // 干扰项：数字但语义不是 RoleId
            new { id = "X_SPECIFIC", type = "bpmn:userTask", properties = new { nodeName = "指定人", approverType = "SpecificUser", approverIds = "1300000000101", approverNames = "超管" } },
            new { id = "X_DEPT", type = "bpmn:userTask", properties = new { nodeName = "部门", approverType = "Department", approverIds = "1300000000002", approverNames = "市场部" } },
            new { id = "end", type = "bpmn:endEvent", properties = new { nodeName = "结束" } },
        },
        edges = new object[] { new { id = "e1", sourceNodeId = "start", targetNodeId = "N1_SUBMIT" } },
    });

    // ───────────── 行为级：解析 ─────────────

    /// <summary>只认 approverType=Role 的数字 token；SpecificUser / Department 的数字不得被当成 RoleId。</summary>
    [Fact]
    public void Parse_OnlyPicksRoleNodes_NotSpecificUserOrDepartment()
    {
        var refs = S6LegacyFlowAuthorityMigrationService.ParseNumericRoleRefs(SampleSnapshot());
        Assert.Equal(2, refs.Count);
        Assert.Equal(new[] { "N2_SUP_REVIEW", "N3_QE_DISPOSITION" }, refs.Select(r => r.NodeId).ToArray());
        Assert.DoesNotContain("1300000000101", refs.SelectMany(r => r.NumericTokens)); // SpecificUser 的 UserId
        Assert.DoesNotContain("1300000000002", refs.SelectMany(r => r.NumericTokens)); // Department 的 OrgId
    }

    /// <summary>Initiator 节点 approverIds 为空串，不算 authority。</summary>
    [Fact]
    public void Parse_IgnoresInitiatorNode()
    {
        var refs = S6LegacyFlowAuthorityMigrationService.ParseNumericRoleRefs(SampleSnapshot());
        Assert.DoesNotContain("N1_SUBMIT", refs.Select(r => r.NodeId));
    }

    /// <summary>已迁过的快照（全 RoleCode）解析不出数字 token —— 这就是幂等判据。</summary>
    [Fact]
    public void Parse_AlreadyMigratedSnapshot_YieldsNothing()
    {
        var refs = S6LegacyFlowAuthorityMigrationService.ParseNumericRoleRefs(
            SampleSnapshot("ROLE_S6_IPQC_SUPERVISOR", "ROLE_S6_IPQC_QUALITY_ENGINEER"));
        Assert.Empty(refs);
    }

    /// <summary>多 token 逐个识别（即使当前实例是单 token）。</summary>
    [Fact]
    public void Parse_HandlesMultipleTokens()
    {
        var refs = S6LegacyFlowAuthorityMigrationService.ParseNumericRoleRefs(SampleSnapshot("111,222,333"));
        var n2 = refs.Single(r => r.NodeId == "N2_SUP_REVIEW");
        Assert.Equal(new[] { "111", "222", "333" }, n2.NumericTokens.ToArray());
    }

    /// <summary>畸形 JSON 不得抛异常，返回空（fail-closed：选不中就不改）。</summary>
    [Theory]
    [InlineData("")]
    [InlineData("not json")]
    [InlineData("{\"nodes\":\"wrong-type\"}")]
    public void Parse_MalformedInput_ReturnsEmpty(string bad)
    {
        Assert.Empty(S6LegacyFlowAuthorityMigrationService.ParseNumericRoleRefs(bad));
    }

    // ───────────── 行为级：改写 ─────────────

    /// <summary>只改 Role 节点的 approverIds；节点集合、名称、edges、approverNames 一概不动。</summary>
    [Fact]
    public void Rewrite_ChangesOnlyRoleApproverIds()
    {
        var before = SampleSnapshot();
        var after = S6LegacyFlowAuthorityMigrationService.RewriteAuthority(before, new Dictionary<string, string>
        {
            ["1329916010002"] = "ROLE_S6_IPQC_SUPERVISOR",
            ["1329916010003"] = "ROLE_S6_IPQC_QUALITY_ENGINEER",
        });
        Assert.NotNull(after);

        var diffs = StructuralDiff(before, after!);
        Assert.Equal(2, diffs.Count);
        Assert.Contains(".nodes[2].properties.approverIds", diffs.Keys);
        Assert.Contains(".nodes[4].properties.approverIds", diffs.Keys);
        Assert.Equal("ROLE_S6_IPQC_SUPERVISOR", diffs[".nodes[2].properties.approverIds"].after);
        Assert.Equal("ROLE_S6_IPQC_QUALITY_ENGINEER", diffs[".nodes[4].properties.approverIds"].after);
    }

    /// <summary>SpecificUser / Department 的数字即使出现在 tokenMap 里也不得被改。</summary>
    [Fact]
    public void Rewrite_NeverTouchesNonRoleNodes()
    {
        var before = SampleSnapshot();
        var after = S6LegacyFlowAuthorityMigrationService.RewriteAuthority(before, new Dictionary<string, string>
        {
            ["1329916010002"] = "ROLE_S6_IPQC_SUPERVISOR",
            ["1300000000101"] = "SHOULD_NOT_BE_APPLIED",   // SpecificUser 的 UserId
            ["1300000000002"] = "SHOULD_NOT_BE_APPLIED",   // Department 的 OrgId
        });
        Assert.NotNull(after);
        Assert.DoesNotContain("SHOULD_NOT_BE_APPLIED", after!);
        Assert.Contains("\"approverIds\":\"1300000000101\"", after);
        Assert.Contains("\"approverIds\":\"1300000000002\"", after);
    }

    /// <summary>多 token 保持原顺序与原数量；未映射的 token 原样留下。</summary>
    [Fact]
    public void Rewrite_PreservesTokenOrderAndCount()
    {
        var after = S6LegacyFlowAuthorityMigrationService.RewriteAuthority(
            SampleSnapshot("111,222,333"), new Dictionary<string, string> { ["222"] = "ROLE_B" });
        Assert.NotNull(after);
        Assert.Contains("\"approverIds\":\"111,ROLE_B,333\"", after!);
    }

    /// <summary>无可改之处时返回 null，调用方据此不发 UPDATE。</summary>
    [Fact]
    public void Rewrite_NoApplicableToken_ReturnsNull()
    {
        Assert.Null(S6LegacyFlowAuthorityMigrationService.RewriteAuthority(
            SampleSnapshot(), new Dictionary<string, string> { ["999999"] = "ROLE_X" }));
    }

    /// <summary>畸形输入返回 null，不抛。</summary>
    [Fact]
    public void Rewrite_MalformedInput_ReturnsNull()
    {
        Assert.Null(S6LegacyFlowAuthorityMigrationService.RewriteAuthority("not json", new Dictionary<string, string>()));
    }

    // ───────────── 源码契约：安全谓词 ─────────────

    /// <summary>BizType 范围必须与引擎的严格守卫白名单逐字一致。</summary>
    [Fact]
    public void Scope_MatchesEngineStrictWhitelist()
    {
        Assert.Equal(new[] { "IPQC_INSPECTION", "S6_PROCESS_INSPECTION" },
            S6LegacyFlowAuthorityMigrationService.TargetBizTypes.ToArray());
        var set = Slice(Engine(), "TenantStrictRoleBizTypes = new(StringComparer.Ordinal)", "};");
        Assert.Contains("\"IPQC_INSPECTION\"", set);
        Assert.Contains("\"S6_PROCESS_INSPECTION\"", set);
    }

    /// <summary>ACTIVE 判据不得只看 Status —— 终态实例的 CurrentNodeId 可能仍停在 N3_*。</summary>
    [Fact]
    public void Selection_RequiresRunningAndPendingTask()
    {
        var body = Slice(Svc(), "public async Task<List<S6MigrationCandidate>> SelectCandidatesAsync", "public async Task<S6FlowAuthorityMigrationResult> MigrateAsync");
        Assert.Contains("x.Status == FlowInstanceStatusEnum.Running", body);
        Assert.Contains("t.Status == FlowTaskStatusEnum.Pending", body);
        Assert.Contains("if (!hasPending) continue;", body);
    }

    /// <summary>§57 终态实例必须被 Running 谓词排除，本服务不得出现「顺带把历史也迁了」的路径。</summary>
    [Fact]
    public void Selection_NeverTouchesTerminalInstances()
    {
        var body = Slice(Svc(), "public async Task<List<S6MigrationCandidate>> SelectCandidatesAsync", "public async Task<S6FlowAuthorityMigrationResult> MigrateAsync");
        Assert.DoesNotContain("FlowInstanceStatusEnum.Approved", body);
        Assert.DoesNotContain("FlowInstanceStatusEnum.Rejected", body);
        Assert.DoesNotContain("FlowInstanceStatusEnum.Cancelled", body);
    }

    /// <summary>批次边界：这是「一次性迁移」与「长期 auto-heal」的分界，未来新坏实例必须响亮失败。</summary>
    [Fact]
    public void Selection_IsBatchScopedByCutoff()
    {
        var s = Svc();
        Assert.Contains("BatchCutoff", s);
        Assert.Contains("x.StartTime < cutoff", s);
    }

    /// <summary>§15 Effective Tenant 必须由业务实体反查，禁止取登录用户租户。</summary>
    [Fact]
    public void Tenant_ResolvedFromBusinessEntity_NotLoginUser()
    {
        var s = Svc();
        var resolver = Slice(s, "private async Task<long?> ResolveEffectiveTenantAsync", "internal static List<S6NumericRoleRef> ParseNumericRoleRefs");
        Assert.Contains("FROM ado_s6_process_inspection_bill WHERE id=@id", resolver);
        Assert.Contains("FROM qms_gcjyd WHERE id=@id", resolver);
        Assert.DoesNotContain("_userManager", s);
        Assert.DoesNotContain("HttpContext", s);
    }

    /// <summary>§58 同租户 numeric RoleId 是合法引用，必须被挡下不改 —— numeric ≠ bad。</summary>
    [Fact]
    public void Mapping_SameTenantNumericRoleId_IsNotMigrated()
    {
        var s = Svc();
        Assert.Contains("legacyRole.TenantId == c.EffectiveTenantId", s);
        Assert.Contains("非跨租户引用，不在迁移范围", s);
    }

    /// <summary>§19 目标角色必须恰好一个启用项，不得 First() 随便挑。</summary>
    [Fact]
    public void Mapping_RequiresExactlyOneEnabledTargetRole()
    {
        var s = Svc();
        Assert.Contains("targets.Count != 1", s);
        Assert.Contains("AMBIGUOUS TARGET ROLE", s);
        Assert.Contains("x.Status == StatusEnum.Enable", s);
    }

    /// <summary>§18 目标角色必须至少有一个同租户成员，否则迁完仍解析 0 人。</summary>
    [Fact]
    public void Mapping_RequiresSameTenantMember()
    {
        var s = Svc();
        Assert.Contains("u.TenantId == c.EffectiveTenantId", s);
        Assert.Contains("if (sameTenantMembers == 0)", s);
        Assert.Contains("BLOCKED_TARGET_AUTHORITY", s);
    }

    /// <summary>§59 任一 token 映射不出来 → 整条实例不迁，禁止部分迁移。</summary>
    [Fact]
    public void Mapping_PartialFailure_AbortsWholeInstance()
    {
        var body = Slice(Svc(), "private async Task MigrateOneAsync", "/// <summary>挡下的候选同样留证");
        // 每个 Block 分支都必须 return，不能继续往下改写
        Assert.Contains("result, _ => result.BlockedByTargetAuthority++);\n                    return;", body);
        Assert.Contains("禁止部分迁移", Svc());
    }

    /// <summary>§20/§21 回滚来源必须恰好 1 行且与当前快照 MD5 一致。</summary>
    [Fact]
    public void RollbackSource_GateRequiresExactlyOneMatchingVersionRow()
    {
        var s = Svc();
        Assert.Contains("v.FlowId == inst.FlowId && v.Version == inst.FlowVersion", s);
        Assert.Contains("versionRows.Count != 1 || usable.Count != 1", s);
        Assert.Contains("BLOCKED_ROLLBACK_SOURCE", s);
    }

    /// <summary>§32 实例表无 version/checksum，UPDATE 必须带改前 MD5 乐观锁且断言 affected==1。</summary>
    [Fact]
    public void Update_UsesBeforeMd5ConcurrencyGuard()
    {
        var s = Svc();
        Assert.Contains("MD5(FlowJsonSnapshot)=@beforeMd5", s);
        Assert.Contains("if (affected != 1)", s);
        Assert.Contains("CONCURRENT MODIFICATION", s);
    }

    /// <summary>§13 留证 INSERT 与快照 UPDATE 必须同一事务。</summary>
    [Fact]
    public void Evidence_AndUpdate_ShareOneTransaction()
    {
        var body = Slice(Svc(), "private async Task MigrateOneAsync", "/// <summary>挡下的候选同样留证");
        var tranAt = body.IndexOf("_db.AsTenant().UseTranAsync(", StringComparison.Ordinal);
        var logAt = body.IndexOf("_logRep.AsInsertable(new AdoS6FlowAuthorityMigrationLog", StringComparison.Ordinal);
        var updAt = body.IndexOf("UPDATE ApprovalFlowInstance", StringComparison.Ordinal);
        Assert.True(tranAt > 0, "缺少事务边界");
        Assert.True(logAt > tranAt, "留证 INSERT 必须在事务内");
        Assert.True(updAt > logAt, "先留证再改写");
        Assert.Contains("if (!tran.IsSuccess)", body);
    }

    /// <summary>§12 留证必须 append-only：不得出现任何删除/清空。</summary>
    [Fact]
    public void Evidence_IsAppendOnly()
    {
        var s = Svc();
        Assert.DoesNotContain("AsDeleteable", s);
        Assert.DoesNotContain("_logRep.AsUpdateable", s);
        Assert.Contains("append-only", Entity());
    }

    /// <summary>§11 留证字段齐全 —— 「为什么改/改前是什么/怎么回滚」必须都能回答。</summary>
    [Theory]
    [InlineData("migration_batch")]
    [InlineData("instance_id")]
    [InlineData("biz_type")]
    [InlineData("biz_id")]
    [InlineData("effective_tenant_id")]
    [InlineData("before_snapshot")]
    [InlineData("after_snapshot")]
    [InlineData("before_md5")]
    [InlineData("after_md5")]
    [InlineData("authority_mapping")]
    [InlineData("rollback_source")]
    [InlineData("reason")]
    [InlineData("outcome")]
    [InlineData("created_at")]
    public void Evidence_HasRequiredColumn(string column)
    {
        Assert.Contains($"ColumnName = \"{column}\"", Entity());
    }

    /// <summary>不得复用 S8 那张每轮全量重写的表 —— 迁移留证一旦被抹掉，回滚依据就消失了。</summary>
    [Fact]
    public void Evidence_DoesNotReuseS8RepairLog()
    {
        Assert.DoesNotContain("AdoS8ApprovalFlowRepairLog", Svc());
        Assert.Contains("ado_s6_flow_authority_migration_log", Entity());
    }

    /// <summary>§27 目标表达必须是 RoleCode，不得写目标租户物理 RoleId。</summary>
    [Fact]
    public void Target_UsesRoleCode_NotTargetLocalRoleId()
    {
        var s = Svc();
        Assert.Contains("tokenMap[token] = code;", s);
        Assert.DoesNotContain("tokenMap[token] = target.Id", s);
    }

    /// <summary>§3/§4 本服务不得触碰引擎、守卫白名单或 resolver —— 它是数据迁移，不是兼容层。</summary>
    [Theory]
    [InlineData("TenantStrictRoleBizTypes")]
    [InlineData("DedicatedEntryOnlyBizTypes")]
    [InlineData("ResolveApprovers")]
    [InlineData("EnsureRoleAuthorityTenantScoped")]
    public void Migration_DoesNotTouchRuntimeGuards(string symbol)
    {
        Assert.DoesNotContain(symbol + "(", Svc());
    }

    /// <summary>§29/§30 不得改历史事实表，也不得切 FlowId/FlowVersion。</summary>
    [Theory]
    [InlineData("UPDATE ApprovalFlowTask")]
    [InlineData("UPDATE ApprovalFlowLog")]
    [InlineData("UPDATE ApprovalFlowCompletedNode")]
    [InlineData("SET FlowId")]
    [InlineData("SET FlowVersion")]
    public void Migration_NeverWritesHistoryOrFlowIdentity(string forbidden)
    {
        Assert.DoesNotContain(forbidden, Svc());
    }

    /// <summary>§31 不得取消旧实例或另起新实例 —— 断言实际调用形态，不误伤文档里提到的 StartFlowCore。</summary>
    [Theory]
    [InlineData("_flowEngine")]
    [InlineData(".StartFlow(")]
    [InlineData(".Withdraw(")]
    [InlineData("Insertable(new ApprovalFlowInstance")]
    public void Migration_NeverRestartsInstance(string forbidden)
    {
        Assert.DoesNotContain(forbidden, Svc());
    }

    private static Dictionary<string, (object? before, object? after)> StructuralDiff(string a, string b)
    {
        var fa = Flatten(JsonNode.Parse(a));
        var fb = Flatten(JsonNode.Parse(b));
        return fa.Keys.Union(fb.Keys)
            .Where(k => !Equals(fa.GetValueOrDefault(k), fb.GetValueOrDefault(k)))
            .ToDictionary(k => k, k => (fa.GetValueOrDefault(k), fb.GetValueOrDefault(k)));
    }

    private static Dictionary<string, object?> Flatten(JsonNode? node, string path = "")
    {
        var flat = new Dictionary<string, object?>();
        switch (node)
        {
            case JsonObject obj:
                foreach (var kv in obj)
                    foreach (var inner in Flatten(kv.Value, $"{path}.{kv.Key}")) flat[inner.Key] = inner.Value;
                break;
            case JsonArray arr:
                for (var i = 0; i < arr.Count; i++)
                    foreach (var inner in Flatten(arr[i], $"{path}[{i}]")) flat[inner.Key] = inner.Value;
                break;
            // 标量统一取原值字符串（不带 JSON 引号），否则断言里要写成 "\"x\"" 影响可读性
            case JsonValue val:
                flat[path] = val.TryGetValue<string>(out var s) ? s : val.ToJsonString();
                break;
            default:
                flat[path] = node?.ToJsonString();
                break;
        }
        return flat;
    }

    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));
    }
}