using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Runtime.InteropServices;
using System.Text;

namespace BizTalkCheckmkPulse.Tests
{
    internal static class Program
    {
        private static readonly List<string> Failures = new List<string>();
        private static int ExecutedTests;

        private static int Main()
        {
            Run("SelfTestEmitsAllStableServices", SelfTestEmitsAllStableServices);
            Run("UnavailableSourcesAreUnknown", UnavailableSourcesAreUnknown);
            Run("UnknownApplicationDoesNotCreateService", UnknownApplicationDoesNotCreateService);
            Run("KnownApplicationCreatesService", KnownApplicationCreatesService);
            Run("ServerNamesAreComparedWithoutWql", ServerNamesAreComparedWithoutWql);
            Run("GroupSettingQueryUsesDocumentedSchema", GroupSettingQueryUsesDocumentedSchema);
            Run("ProviderSqlLoginFailureIsPermission", ProviderSqlLoginFailureIsPermission);
            Run("RejectedSqlPrincipalIsExtracted", RejectedSqlPrincipalIsExtracted);
            Run("PlatformPermissionPropagatesToSqlDiscovery", PlatformPermissionPropagatesToSqlDiscovery);
            Run("RoutingFailureReportsAreCounted", RoutingFailureReportsAreCounted);
            Run("ReceiveLocationAllowlistSeparatesExpectedState", ReceiveLocationAllowlistSeparatesExpectedState);
            Run("UnknownReceiveLocationStateIsNotGreen", UnknownReceiveLocationStateIsNotGreen);
            Run("SendPortAllowlistSeparatesExpectedState", SendPortAllowlistSeparatesExpectedState);
            Run("ArtifactSummaryIsBounded", ArtifactSummaryIsBounded);
            Run("EndpointAddressesResolveWithoutSecrets", EndpointAddressesResolveWithoutSecrets);
            Run("EndpointCatalogPreservesManualOverrides", EndpointCatalogPreservesManualOverrides);
            Run("EndpointCatalogRoundTrip", EndpointCatalogRoundTrip);
            Run("EndpointOutputListsOnlyUnavailableTargets", EndpointOutputListsOnlyUnavailableTargets);
            Run("EndpointProbeBudgetFitsMinuteInterval", EndpointProbeBudgetFitsMinuteInterval);
            Run("InstallerUpdatePreservesExistingSettings", InstallerUpdatePreservesExistingSettings);
            Run("SnapshotRoundTripPreservesLines", SnapshotRoundTripPreservesLines);
            Run("SnapshotRejectsTampering", SnapshotRejectsTampering);
            Run("SnapshotRejectsStaleData", SnapshotRejectsStaleData);
            Run("SnapshotRejectsDifferentMachine", SnapshotRejectsDifferentMachine);
            Run("SnapshotReportsMissingFile", SnapshotReportsMissingFile);
            Run("SnapshotFailureEmitsStableUnknownServices", SnapshotFailureEmitsStableUnknownServices);

            if (Failures.Count == 0)
            {
                Console.WriteLine("PASS: " + ExecutedTests + " tests");
                return 0;
            }

            foreach (var failure in Failures)
            {
                Console.Error.WriteLine("FAIL: " + failure);
            }

            return 1;
        }

        private static void SelfTestEmitsAllStableServices()
        {
            var lines = new CheckmkLocalFormatter(new MonitoringOptions()).FormatSelfTest().ToArray();
            AssertEqual(9, lines.Length, "self-test line count");
            AssertEqual(9, lines.Distinct(StringComparer.Ordinal).Count(), "unique self-test lines");
            Assert(lines.All(x => x.StartsWith("0 \"BizTalk ", StringComparison.Ordinal)), "every self-test line must be OK");
            Assert(lines.Any(x => x.Contains("\"BizTalk Event Log\"")), "Event Log service missing");
            Assert(lines.Any(x => x.Contains("\"BizTalk Receive Locations\"")), "Receive Locations service missing");
            Assert(lines.Any(x => x.Contains("\"BizTalk Send Ports\"")), "Send Ports service missing");
            Assert(lines.Any(x => x.Contains("\"BizTalk Endpoint Reachability\"")), "Endpoint Reachability service missing");
            Assert(lines.Any(x => x.Contains("\"BizTalk Orchestrations\"")), "Orchestrations service missing");
        }

        private static void UnavailableSourcesAreUnknown()
        {
            var lines = new CheckmkLocalFormatter(new MonitoringOptions()).Format(new ProbeResult()).Take(9).ToArray();
            AssertEqual(9, lines.Length, "stable service count");
            Assert(lines.All(x => x.StartsWith("3 \"BizTalk ", StringComparison.Ordinal)), "unavailable sources must be UNKNOWN");
        }

        private static void UnknownApplicationDoesNotCreateService()
        {
            var options = new MonitoringOptions { EmitPerApplicationSuspensionServices = true };
            var result = CreateSuspensionResult("(unknown)");
            var lines = new CheckmkLocalFormatter(options).Format(result).ToArray();
            AssertEqual(9, lines.Length, "unknown application must not create a dynamic service");
        }

        private static void KnownApplicationCreatesService()
        {
            var options = new MonitoringOptions { EmitPerApplicationSuspensionServices = true };
            var result = CreateSuspensionResult("Orders");
            var lines = new CheckmkLocalFormatter(options).Format(result).ToArray();
            AssertEqual(10, lines.Length, "known application should create one dynamic service");
            Assert(lines.Any(x => x.Contains("\"BizTalk Suspended Orders\"")), "known application service missing");
        }

        private static void ServerNamesAreComparedWithoutWql()
        {
            Assert(WmiBizTalkProbe.IsSameServer("BIZTALK01.corp.example", "biztalk01"), "FQDN and short name must match");
            Assert(WmiBizTalkProbe.IsSameServer(@"\\BIZ-TALK+01", "biz-talk+01.example"), "special characters must be compared client-side");
            Assert(!WmiBizTalkProbe.IsSameServer("BIZTALK01", "BIZTALK02"), "different servers must not match");
        }

        private static void GroupSettingQueryUsesDocumentedSchema()
        {
            var query = WmiBizTalkProbe.GroupSettingQuery;
            Assert(query.Contains("FROM MSBTS_GroupSetting"), "MSBTS_GroupSetting query missing");
            Assert(query.Contains("BizTalkOperatorGroup"), "configured operator group property missing");
            Assert(query.Contains("BizTalkReadOnlyUserGroup"), "configured read-only group property missing");
            Assert(query.Contains("SubscriptionDBServerName"), "master MessageBox server property missing");
            Assert(query.Contains("SubscriptionDBName"), "master MessageBox database property missing");
            Assert(query.IndexOf("MessageBoxSetting", StringComparison.OrdinalIgnoreCase) < 0, "unsupported MessageBoxSetting class present");
            Assert(WmiBizTalkProbe.SuspendedInstancesQuery.Contains("ServiceClass = 64"), "routing failure report filter missing");
        }

        private static void ProviderSqlLoginFailureIsPermission()
        {
            var exception = new COMException(
                "Internal error from OLEDB provider: 'Login failed for user 'BEW\\AV23AGPWBIO1$'.'",
                unchecked((int)0x80131904));
            AssertEqual(
                DiagnosticCategory.Permission,
                WmiBizTalkProbe.ClassifyWmiException(exception),
                "provider SQL login classification");
        }

        private static void RejectedSqlPrincipalIsExtracted()
        {
            var message = "Internal error from OLEDB provider: 'Login failed for user 'BEW\\AV23AGPWBIO1$'.'";
            AssertEqual(
                "BEW\\AV23AGPWBIO1$",
                WmiBizTalkProbe.ExtractSqlLoginPrincipal(message),
                "rejected SQL principal");
        }

        private static void PlatformPermissionPropagatesToSqlDiscovery()
        {
            var result = new ProbeResult();
            result.Diagnostics.Add(new ProbeDiagnostic
            {
                Area = DiagnosticArea.Wmi,
                Category = DiagnosticCategory.Permission,
                Component = "MSBTS_GroupSetting",
                Required = true
            });

            new SqlConnectivityProbe(new MonitoringOptions()).Query(result);

            var discovery = result.Diagnostics.Single(x =>
                x.Area == DiagnosticArea.Sql
                && x.Component == "BizTalk database discovery");
            AssertEqual(
                DiagnosticCategory.Permission,
                discovery.Category,
                "SQL discovery classification");
        }

        private static void RoutingFailureReportsAreCounted()
        {
            var result = new ProbeResult();
            result.Platform.SuspendedInstancesDataAvailable = true;
            result.SuspendedInstances.Add(new SuspendedInstance
            {
                ApplicationName = "(unknown)",
                ServiceName = string.Empty,
                ServiceClassId = 64,
                Kind = SuspendedKind.NonResumable
            });
            result.SuspendedInstances.Add(new SuspendedInstance
            {
                ApplicationName = "Orders",
                ServiceName = "Receive.Order",
                Kind = SuspendedKind.Resumable
            });

            var line = FindServiceLine(result, "Suspended Instances");
            Assert(line.StartsWith("2 \"BizTalk Suspended Instances\"", StringComparison.Ordinal), "routing failure must be CRIT");
            Assert(line.Contains("biztalk_suspended_total=2"), "suspended total metric missing");
            Assert(line.Contains("biztalk_suspended_nonresumable=1"), "non-resumable metric missing");
            Assert(line.Contains("biztalk_routing_failure_reports=1"), "routing failure metric missing");
            Assert(line.Contains("routing_failure_reports=1"), "routing failure summary missing");
        }

        private static void ReceiveLocationAllowlistSeparatesExpectedState()
        {
            var options = new MonitoringOptions
            {
                ExpectedDisabledReceiveLocations = new[] { "Maintenance\\RL Expected" }
            };
            var result = new ProbeResult();
            result.Platform.ReceiveLocationsDataAvailable = true;
            result.ReceiveLocations.Add(new ReceiveLocationState
            {
                ApplicationName = "Maintenance",
                Name = "RL Expected",
                IsDisabled = true
            });
            result.ReceiveLocations.Add(new ReceiveLocationState
            {
                ApplicationName = "Orders",
                Name = "RL Orders",
                IsDisabled = true
            });
            result.ReceiveLocations.Add(new ReceiveLocationState
            {
                ApplicationName = "Orders",
                Name = "RL Active",
                IsDisabled = false
            });

            var line = FindServiceLine(result, "Receive Locations", options);
            Assert(line.StartsWith("2 \"BizTalk Receive Locations\"", StringComparison.Ordinal), "unexpected disabled receive location must be CRIT");
            Assert(line.Contains("biztalk_receive_locations_enabled=1"), "enabled receive metric missing");
            Assert(line.Contains("biztalk_receive_locations_unexpected_disabled=1"), "unexpected disabled metric missing");
            Assert(line.Contains("biztalk_receive_locations_expected_disabled=1"), "expected disabled metric missing");
            Assert(line.Contains(@"Orders\RL Orders"), "affected receive location missing");
            Assert(line.IndexOf("RL Expected", StringComparison.Ordinal) < 0, "expected disabled receive location should not clutter affected list");

            options.ExpectedDisabledReceiveLocations = new[] { "Maintenance\\RL Expected", "RL Orders" };
            var allExpected = FindServiceLine(result, "Receive Locations", options);
            Assert(allExpected.StartsWith("0 \"BizTalk Receive Locations\"", StringComparison.Ordinal), "all expected disabled receive locations should be OK");
            Assert(allExpected.Contains("biztalk_receive_locations_expected_disabled=2"), "all expected receive count missing");
        }

        private static void SendPortAllowlistSeparatesExpectedState()
        {
            var options = new MonitoringOptions
            {
                ExpectedInactiveSendPorts = new[] { "Maintenance\\SP Expected" }
            };
            var result = new ProbeResult();
            result.Platform.SendPortsDataAvailable = true;
            result.SendPorts.Add(new SendPortState
            {
                ApplicationName = "Maintenance",
                Name = "SP Expected",
                Status = 2
            });
            result.SendPorts.Add(new SendPortState
            {
                ApplicationName = "Orders",
                Name = "SP Orders",
                Status = 1
            });
            result.SendPorts.Add(new SendPortState
            {
                ApplicationName = "Orders",
                Name = "SP Active",
                Status = 3
            });

            var line = FindServiceLine(result, "Send Ports", options);
            Assert(line.StartsWith("2 \"BizTalk Send Ports\"", StringComparison.Ordinal), "unexpected inactive send port must be CRIT");
            Assert(line.Contains("biztalk_send_ports_started=1"), "started send port metric missing");
            Assert(line.Contains("biztalk_send_ports_unexpected_inactive=1"), "unexpected inactive send metric missing");
            Assert(line.Contains("biztalk_send_ports_expected_inactive=1"), "expected inactive send metric missing");
            Assert(line.Contains(@"Orders\SP Orders(bound)"), "affected send port missing");
            Assert(line.IndexOf("SP Expected", StringComparison.Ordinal) < 0, "expected inactive send port should not clutter affected list");

            options.ExpectedInactiveSendPorts = new[] { "Maintenance\\SP Expected", "SP Orders" };
            var allExpected = FindServiceLine(result, "Send Ports", options);
            Assert(allExpected.StartsWith("0 \"BizTalk Send Ports\"", StringComparison.Ordinal), "all expected inactive send ports should be OK");
            Assert(allExpected.Contains("biztalk_send_ports_expected_inactive=2"), "all expected send count missing");
        }

        private static void UnknownReceiveLocationStateIsNotGreen()
        {
            var result = new ProbeResult();
            result.Platform.ReceiveLocationsDataAvailable = true;
            result.ReceiveLocations.Add(new ReceiveLocationState
            {
                ApplicationName = "Orders",
                Name = "RL Missing State",
                IsDisabled = null
            });

            var line = FindServiceLine(result, "Receive Locations");
            Assert(line.StartsWith("3 \"BizTalk Receive Locations\"", StringComparison.Ordinal), "unknown receive state must be UNKNOWN");
            Assert(line.Contains("biztalk_receive_locations_unknown=1"), "unknown receive metric missing");
            Assert(line.Contains(@"Orders\RL Missing State"), "unknown receive location must be visible");
        }

        private static void ArtifactSummaryIsBounded()
        {
            var options = new MonitoringOptions
            {
                MaxSummaryItems = 2,
                MaxDetailCharacters = 256
            };
            var result = new ProbeResult();
            result.Platform.ReceiveLocationsDataAvailable = true;
            for (var i = 1; i <= 6; i++)
            {
                result.ReceiveLocations.Add(new ReceiveLocationState
                {
                    ApplicationName = "Application",
                    Name = "Disabled-" + i,
                    IsDisabled = true
                });
            }

            var line = FindServiceLine(result, "Receive Locations", options);
            Assert(line.Contains("(+4 more)"), "omitted item count missing");
            Assert(line.Length < 700, "local check line should remain compact");

            var longResult = new ProbeResult();
            longResult.Platform.ReceiveLocationsDataAvailable = true;
            longResult.ReceiveLocations.Add(new ReceiveLocationState
            {
                ApplicationName = new string('A', 400),
                Name = new string('R', 400),
                IsDisabled = true
            });
            var truncated = FindServiceLine(longResult, "Receive Locations", options);
            Assert(truncated.Contains("[truncated]"), "detail character limit should be visible");
            Assert(truncated.Length < 700, "truncated local check line should remain bounded");
        }

        private static void SnapshotRoundTripPreservesLines()
        {
            WithTemporarySnapshot((path, store) =>
            {
                var lines = new CheckmkLocalFormatter(new MonitoringOptions()).FormatSelfTest().ToArray();
                var generated = DateTime.UtcNow;
                store.Write(lines, generated, "DOMAIN\\collector$");
                var result = store.Read(generated.AddSeconds(10), TimeSpan.FromMinutes(3));

                Assert(result.IsSuccess, "snapshot should be readable: " + result.Error);
                AssertEqual(lines.Length, result.Lines.Count, "snapshot line count");
                Assert(lines.SequenceEqual(result.Lines), "snapshot payload changed");

                var replacement = lines.Select(x => x.Replace("Self test OK", "Replacement OK")).ToArray();
                store.Write(replacement, generated.AddSeconds(30), "DOMAIN\\collector$");
                var replaced = store.Read(generated.AddSeconds(40), TimeSpan.FromMinutes(3));
                Assert(replaced.IsSuccess, "replaced snapshot should be readable");
                Assert(replacement.SequenceEqual(replaced.Lines), "atomic replacement payload changed");
            });
        }

        private static void EndpointAddressesResolveWithoutSecrets()
        {
            EndpointCatalogEntry endpoint;
            string reason;
            var candidate = new EndpointCandidate
            {
                ArtifactType = "SendPort",
                ApplicationName = "Orders",
                ArtifactName = "SP Orders",
                TransportRole = "Primary",
                AdapterName = "WCF-BasicHttp",
                Address = "https://api-user:top-secret@example.test/orders?q=secret",
                Active = true
            };
            Assert(EndpointAddressParser.TryCreate(candidate, out endpoint, out reason), "HTTPS endpoint should resolve: " + reason);
            AssertEqual("example.test", endpoint.Host, "HTTPS host");
            AssertEqual(443, endpoint.Port, "HTTPS port");
            Assert(endpoint.Key.IndexOf("secret", StringComparison.OrdinalIgnoreCase) < 0, "catalog key must not contain URI secrets");
            Assert(endpoint.Host.IndexOf("secret", StringComparison.OrdinalIgnoreCase) < 0, "catalog host must not contain URI secrets");

            candidate.Address = @"\\fileserver\drop\%MessageID%.xml";
            candidate.AdapterName = "FILE";
            Assert(EndpointAddressParser.TryCreate(candidate, out endpoint, out reason), "UNC endpoint should resolve: " + reason);
            AssertEqual("fileserver", endpoint.Host, "UNC host");
            AssertEqual(445, endpoint.Port, "UNC SMB port");

            candidate.Address = "recipient@example.test";
            candidate.AdapterName = "SMTP";
            Assert(!EndpointAddressParser.TryCreate(candidate, out endpoint, out reason), "SMTP recipient must not become a host probe");
            Assert(!EndpointAddressParser.IsPotentialExternalEndpoint(candidate), "SMTP recipient must not cause UNKNOWN");

            candidate.Address = "/Orders/Receive.svc";
            candidate.AdapterName = "WCF-CustomIsolated";
            Assert(!EndpointAddressParser.IsPotentialExternalEndpoint(candidate), "relative local receive address must not cause UNKNOWN");
        }

        private static void EndpointCatalogPreservesManualOverrides()
        {
            var candidate = new EndpointCandidate
            {
                ArtifactType = "SendPort",
                ApplicationName = "Orders",
                ArtifactName = "SP Orders",
                TransportRole = "Primary",
                AdapterName = "SFTP",
                Address = "sftp://discovered.example.test/out",
                Active = true
            };
            var inactive = new EndpointCandidate
            {
                ArtifactType = "ReceiveLocation",
                ApplicationName = "Orders",
                ArtifactName = "RL Disabled",
                TransportRole = "Inbound",
                AdapterName = "HTTPS",
                Address = "https://disabled.example.test/in",
                Active = false
            };
            var existing = new EndpointCatalog { EnvironmentName = "ACC" };
            existing.Entries.Add(new EndpointCatalogEntry
            {
                Key = candidate.Key,
                ArtifactType = candidate.ArtifactType,
                ApplicationName = candidate.ApplicationName,
                ArtifactName = candidate.ArtifactName,
                TransportRole = candidate.TransportRole,
                AdapterName = candidate.AdapterName,
                Protocol = "TCP",
                Host = "manual.example.test",
                Port = 2222,
                Enabled = true,
                AutoDiscovered = false
            });

            var synchronized = EndpointConnectivityProbe.SynchronizeCatalog(existing, new[] { candidate, inactive }, DateTime.UtcNow);
            AssertEqual(1, synchronized.Entries.Count, "manual override count");
            AssertEqual("manual.example.test", synchronized.Entries[0].Host, "manual override host");
            AssertEqual(2222, synchronized.Entries[0].Port, "manual override port");
            Assert(!synchronized.Entries[0].AutoDiscovered, "manual override marker");
            Assert(synchronized.Entries.All(x => x.ArtifactName != "RL Disabled"), "inactive receive location must not be added");
        }

        private static void EndpointOutputListsOnlyUnavailableTargets()
        {
            var result = new ProbeResult();
            result.EndpointConnectivity.RuntimeStateAvailable = true;
            result.EndpointConnectivity.CatalogAvailable = true;
            result.EndpointConnectivity.RefreshSucceeded = true;
            result.EndpointConnectivity.Configured = 2;
            result.EndpointConnectivity.Active = 2;
            result.EndpointConnectivity.Results.Add(new EndpointProbeResult
            {
                Endpoint = TestEndpoint("Reachable", "up.example.test"),
                Available = true
            });
            result.EndpointConnectivity.Results.Add(new EndpointProbeResult
            {
                Endpoint = TestEndpoint("Unavailable", "down.example.test"),
                Available = false,
                Failure = "TCP timeout"
            });

            var line = FindServiceLine(result, "Endpoint Reachability");
            Assert(line.StartsWith("2 \"BizTalk Endpoint Reachability\"", StringComparison.Ordinal), "failed endpoint must be CRIT");
            Assert(line.Contains("Unavailable"), "unavailable endpoint name missing");
            Assert(line.Contains("down.example.test:443/TCP"), "unavailable host missing");
            Assert(line.IndexOf("Reachable", StringComparison.Ordinal) < 0, "reachable endpoint must not clutter output");
            Assert(line.IndexOf("up.example.test", StringComparison.Ordinal) < 0, "reachable host must not clutter output");
        }

        private static void EndpointCatalogRoundTrip()
        {
            var directory = Path.Combine(Path.GetTempPath(), "BizTalkCheckmkPulse.CatalogTests." + Guid.NewGuid().ToString("N"));
            Directory.CreateDirectory(directory);
            var path = Path.Combine(directory, "endpoints.xml");
            try
            {
                var catalog = new EndpointCatalog
                {
                    EnvironmentName = "ACC",
                    SynchronizedUtc = DateTime.UtcNow,
                    ActiveCandidates = 150,
                    UnsupportedCandidates = 0
                };
                catalog.Entries.Add(TestEndpoint("Orders", "api.example.test"));
                var store = new EndpointCatalogStore(path, 1048576, 100);
                store.Write(catalog);
                var loaded = store.Read("ACC");

                AssertEqual(1, loaded.Entries.Count, "catalog entry count");
                AssertEqual("api.example.test", loaded.Entries[0].Host, "catalog host");
                AssertEqual(443, loaded.Entries[0].Port, "catalog port");
                Assert(File.ReadAllText(path).IndexOf("top-secret", StringComparison.OrdinalIgnoreCase) < 0, "catalog must not contain URI secrets");
            }
            finally
            {
                if (Directory.Exists(directory))
                {
                    Directory.Delete(directory, true);
                }
            }
        }

        private static EndpointCatalogEntry TestEndpoint(string name, string host)
        {
            return new EndpointCatalogEntry
            {
                Key = name,
                ArtifactType = "SendPort",
                ApplicationName = "Orders",
                ArtifactName = name,
                TransportRole = "Primary",
                Protocol = "TCP",
                Host = host,
                Port = 443,
                Enabled = true,
                AutoDiscovered = true
            };
        }

        private static void EndpointProbeBudgetFitsMinuteInterval()
        {
            var options = new MonitoringOptions();
            var seventyTargets = EndpointConnectivityProbe.CalculateWorstCaseProbeMilliseconds(
                70,
                options.EndpointProbeMaxConcurrency,
                options.EndpointProbeTimeoutMilliseconds);
            var configuredMaximum = EndpointConnectivityProbe.CalculateWorstCaseProbeMilliseconds(
                options.EndpointMaxCount,
                options.EndpointProbeMaxConcurrency,
                options.EndpointProbeTimeoutMilliseconds);

            AssertEqual(15000, (int)seventyTargets, "70-target theoretical timeout budget");
            Assert(configuredMaximum <= 30000, "configured endpoint worst-case must leave headroom in the minute interval");
        }

        private static void InstallerUpdatePreservesExistingSettings()
        {
            var directory = Path.Combine(Path.GetTempPath(), "BizTalkCheckmkPulse.InstallerTests." + Guid.NewGuid().ToString("N"));
            Directory.CreateDirectory(directory);
            try
            {
                var source = Path.Combine(directory, "source.config");
                var existing = Path.Combine(directory, "existing.config");
                var staged = Path.Combine(directory, "staged.config");
                File.WriteAllText(
                    source,
                    "<configuration><appSettings>"
                    + "<add key=\"EnvironmentName\" value=\"\" />"
                    + "<add key=\"EndpointProbeMaxConcurrency\" value=\"16\" />"
                    + "<add key=\"EndpointMaxCount\" value=\"100\" />"
                    + "<add key=\"NewSetting\" value=\"new-default\" />"
                    + "</appSettings></configuration>",
                    new UTF8Encoding(false));
                File.WriteAllText(
                    existing,
                    "<configuration><appSettings>"
                    + "<add key=\"EnvironmentName\" value=\"ACC\" />"
                    + "<add key=\"EndpointProbeMaxConcurrency\" value=\"7\" />"
                    + "<add key=\"EndpointMaxCount\" value=\"500\" />"
                    + "<add key=\"RemovedLegacySetting\" value=\"legacy\" />"
                    + "</appSettings></configuration>",
                    new UTF8Encoding(false));

                var effectiveEnvironment = BizTalkCheckmkPulse.Setup.InstallerEngine.PrepareConfig(
                    source,
                    staged,
                    existing,
                    string.Empty);
                var merged = File.ReadAllText(staged);
                AssertEqual("ACC", effectiveEnvironment, "preserved installer environment");
                Assert(merged.Contains("key=\"EndpointProbeMaxConcurrency\" value=\"7\""), "existing operational value must be preserved");
                Assert(merged.Contains("key=\"EndpointMaxCount\" value=\"100\""), "superseded old default must migrate to new bounded default");
                Assert(merged.Contains("key=\"NewSetting\" value=\"new-default\""), "new source setting must be added");
                Assert(merged.IndexOf("RemovedLegacySetting", StringComparison.Ordinal) < 0, "removed legacy key must not be resurrected");

                effectiveEnvironment = BizTalkCheckmkPulse.Setup.InstallerEngine.PrepareConfig(
                    source,
                    staged,
                    existing,
                    "PRD");
                AssertEqual("PRD", effectiveEnvironment, "requested environment override");
            }
            finally
            {
                if (Directory.Exists(directory)) Directory.Delete(directory, true);
            }
        }

        private static void SnapshotRejectsTampering()
        {
            WithTemporarySnapshot((path, store) =>
            {
                var lines = new CheckmkLocalFormatter(new MonitoringOptions()).FormatSelfTest().ToArray();
                store.Write(lines, DateTime.UtcNow, "DOMAIN\\collector$");
                var content = File.ReadAllText(path, Encoding.UTF8);
                File.WriteAllText(path, content.Replace("Self test OK", "Tampered output"), new UTF8Encoding(false));

                var result = store.Read(DateTime.UtcNow, TimeSpan.FromMinutes(3));
                Assert(!result.IsSuccess, "tampered snapshot must be rejected");
                Assert(result.Error.IndexOf("SHA-256", StringComparison.OrdinalIgnoreCase) >= 0, "tamper reason should mention SHA-256");
            });
        }

        private static void SnapshotRejectsStaleData()
        {
            WithTemporarySnapshot((path, store) =>
            {
                var lines = new CheckmkLocalFormatter(new MonitoringOptions()).FormatSelfTest().ToArray();
                var generated = DateTime.UtcNow.AddMinutes(-10);
                store.Write(lines, generated, "DOMAIN\\collector$");

                var result = store.Read(DateTime.UtcNow, TimeSpan.FromMinutes(3));
                Assert(!result.IsSuccess, "stale snapshot must be rejected");
                Assert(result.Error.IndexOf("stale", StringComparison.OrdinalIgnoreCase) >= 0, "stale reason missing");
            });
        }

        private static void SnapshotRejectsDifferentMachine()
        {
            WithTemporarySnapshot((path, store) =>
            {
                var lines = new CheckmkLocalFormatter(new MonitoringOptions()).FormatSelfTest().ToArray();
                store.Write(lines, DateTime.UtcNow, "DOMAIN\\collector$");
                var content = File.ReadAllText(path, Encoding.UTF8);
                var currentMachine = Convert.ToBase64String(Encoding.UTF8.GetBytes(Environment.MachineName));
                var otherMachine = Convert.ToBase64String(Encoding.UTF8.GetBytes("OTHER-SERVER"));
                File.WriteAllText(
                    path,
                    content.Replace("machineBase64=" + currentMachine, "machineBase64=" + otherMachine),
                    new UTF8Encoding(false));

                var result = store.Read(DateTime.UtcNow, TimeSpan.FromMinutes(3));
                Assert(!result.IsSuccess, "snapshot for another machine must be rejected");
                Assert(result.Error.IndexOf("different machine", StringComparison.OrdinalIgnoreCase) >= 0, "machine mismatch reason missing");
            });
        }

        private static void SnapshotReportsMissingFile()
        {
            WithTemporarySnapshot((path, store) =>
            {
                var result = store.Read(DateTime.UtcNow, TimeSpan.FromMinutes(3));
                Assert(!result.IsSuccess, "missing snapshot must be rejected");
                Assert(result.Error.IndexOf("does not exist", StringComparison.OrdinalIgnoreCase) >= 0, "missing file reason missing");
            });
        }

        private static void SnapshotFailureEmitsStableUnknownServices()
        {
            var lines = new CheckmkLocalFormatter(new MonitoringOptions())
                .FormatSnapshotFailure("Snapshot file does not exist.")
                .ToArray();
            AssertEqual(9, lines.Length, "snapshot failure stable service count");
            Assert(lines.All(x => x.StartsWith("3 \"BizTalk ", StringComparison.Ordinal)), "snapshot failure must be UNKNOWN");
            Assert(lines.All(x => x.Contains("Scheduled Task")), "snapshot failure must contain provider action");
        }

        private static void WithTemporarySnapshot(Action<string, SnapshotStore> test)
        {
            var directory = Path.Combine(Path.GetTempPath(), "BizTalkCheckmkPulse.Tests." + Guid.NewGuid().ToString("N"));
            Directory.CreateDirectory(directory);
            var path = Path.Combine(directory, "snapshot.txt");
            try
            {
                test(path, new SnapshotStore(path, 1048576));
            }
            finally
            {
                if (Directory.Exists(directory))
                {
                    Directory.Delete(directory, true);
                }
            }
        }

        private static ProbeResult CreateSuspensionResult(string applicationName)
        {
            var result = new ProbeResult();
            result.Platform.SuspendedInstancesDataAvailable = true;
            result.SuspendedInstances.Add(new SuspendedInstance
            {
                ApplicationName = applicationName,
                ServiceName = "TestService",
                Kind = SuspendedKind.Resumable
            });
            return result;
        }

        private static string FindServiceLine(
            ProbeResult result,
            string serviceSuffix,
            MonitoringOptions options = null)
        {
            var effectiveOptions = options ?? new MonitoringOptions();
            var token = "\"" + effectiveOptions.ServiceName(serviceSuffix) + "\"";
            return new CheckmkLocalFormatter(effectiveOptions)
                .Format(result)
                .Single(x => x.Contains(token));
        }

        private static void Run(string name, Action test)
        {
            ExecutedTests++;
            try
            {
                test();
            }
            catch (Exception ex)
            {
                Failures.Add(name + ": " + ex.Message);
            }
        }

        private static void Assert(bool condition, string message)
        {
            if (!condition)
            {
                throw new InvalidOperationException(message);
            }
        }

        private static void AssertEqual(int expected, int actual, string label)
        {
            if (expected != actual)
            {
                throw new InvalidOperationException(label + ": expected " + expected + ", actual " + actual);
            }
        }

        private static void AssertEqual(DiagnosticCategory expected, DiagnosticCategory actual, string label)
        {
            if (expected != actual)
            {
                throw new InvalidOperationException(label + ": expected " + expected + ", actual " + actual);
            }
        }

        private static void AssertEqual(string expected, string actual, string label)
        {
            if (!string.Equals(expected, actual, StringComparison.Ordinal))
            {
                throw new InvalidOperationException(label + ": expected " + expected + ", actual " + actual);
            }
        }
    }
}