added ticket dashboard backend: data models, CRUD, AI diagnosis service, and 9 controller endpoints

Week 1 of ticket dashboard MVP — backend only:
- 4 new SQLite tables: Ticket, TicketComment, TicketAiDiagnosis, TicketTimelineEvent
- CRUD methods in Database/ partial classes with cascade delete
- TicketDiagnosticService for async Mistral AI diagnosis (fire-and-forget)
- 9 admin-only Controller endpoints for ticket CRUD, comments, and detail view
- Ticket cleanup integrated into Delete(Installation) cascade

csharp/App/Backend/Controller.cs

@@ -1746,6 +1746,172 @@ public class Controller : ControllerBase
         return Ok(result);
     }
 
+    // ═══════════════════════════════════════════════
+    // TICKET ENDPOINTS (admin-only)
+    // ═══════════════════════════════════════════════
+
+    [HttpGet(nameof(GetAllTickets))]
+    public ActionResult<IEnumerable<Ticket>> GetAllTickets(Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user is null || user.UserType != 2) return Unauthorized();
+
+        return Db.GetAllTickets();
+    }
+
+    [HttpGet(nameof(GetTicketsForInstallation))]
+    public ActionResult<IEnumerable<Ticket>> GetTicketsForInstallation(Int64 installationId, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user is null || user.UserType != 2) return Unauthorized();
+
+        var installation = Db.GetInstallationById(installationId);
+        if (installation is null) return NotFound();
+
+        return Db.GetTicketsForInstallation(installationId);
+    }
+
+    [HttpGet(nameof(GetTicketById))]
+    public ActionResult<Ticket> GetTicketById(Int64 id, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user is null || user.UserType != 2) return Unauthorized();
+
+        var ticket = Db.GetTicketById(id);
+        return ticket is null ? NotFound() : ticket;
+    }
+
+    [HttpPost(nameof(CreateTicket))]
+    public ActionResult<Ticket> CreateTicket([FromBody] Ticket ticket, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user is null || user.UserType != 2) return Unauthorized();
+
+        ticket.CreatedByUserId = user.Id;
+        ticket.CreatedAt       = DateTime.UtcNow;
+        ticket.UpdatedAt       = DateTime.UtcNow;
+        ticket.Status          = (Int32)TicketStatus.Open;
+
+        if (!Db.Create(ticket)) return StatusCode(500, "Failed to create ticket.");
+
+        Db.Create(new TicketTimelineEvent
+        {
+            TicketId    = ticket.Id,
+            EventType   = (Int32)TimelineEventType.Created,
+            Description = $"Ticket created by {user.Name}.",
+            ActorType   = (Int32)TimelineActorType.Human,
+            ActorId     = user.Id,
+            CreatedAt   = DateTime.UtcNow
+        });
+
+        // Fire-and-forget AI diagnosis
+        TicketDiagnosticService.DiagnoseTicketAsync(ticket.Id).SupressAwaitWarning();
+
+        return ticket;
+    }
+
+    [HttpPut(nameof(UpdateTicket))]
+    public ActionResult<Ticket> UpdateTicket([FromBody] Ticket ticket, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user is null || user.UserType != 2) return Unauthorized();
+
+        var existing = Db.GetTicketById(ticket.Id);
+        if (existing is null) return NotFound();
+
+        ticket.CreatedAt       = existing.CreatedAt;
+        ticket.CreatedByUserId = existing.CreatedByUserId;
+        ticket.UpdatedAt       = DateTime.UtcNow;
+
+        if (ticket.Status != existing.Status)
+        {
+            if (ticket.Status == (Int32)TicketStatus.Resolved)
+                ticket.ResolvedAt = DateTime.UtcNow;
+
+            Db.Create(new TicketTimelineEvent
+            {
+                TicketId    = ticket.Id,
+                EventType   = (Int32)TimelineEventType.StatusChanged,
+                Description = $"Status changed to {(TicketStatus)ticket.Status}.",
+                ActorType   = (Int32)TimelineActorType.Human,
+                ActorId     = user.Id,
+                CreatedAt   = DateTime.UtcNow
+            });
+        }
+
+        return Db.Update(ticket) ? ticket : StatusCode(500, "Update failed.");
+    }
+
+    [HttpDelete(nameof(DeleteTicket))]
+    public ActionResult DeleteTicket(Int64 id, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user is null || user.UserType != 2) return Unauthorized();
+
+        var ticket = Db.GetTicketById(id);
+        if (ticket is null) return NotFound();
+
+        return Db.Delete(ticket) ? Ok() : StatusCode(500, "Delete failed.");
+    }
+
+    [HttpGet(nameof(GetTicketComments))]
+    public ActionResult<IEnumerable<TicketComment>> GetTicketComments(Int64 ticketId, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user is null || user.UserType != 2) return Unauthorized();
+
+        return Db.GetCommentsForTicket(ticketId);
+    }
+
+    [HttpPost(nameof(AddTicketComment))]
+    public ActionResult<TicketComment> AddTicketComment([FromBody] TicketComment comment, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user is null || user.UserType != 2) return Unauthorized();
+
+        var ticket = Db.GetTicketById(comment.TicketId);
+        if (ticket is null) return NotFound();
+
+        comment.AuthorType = (Int32)CommentAuthorType.Human;
+        comment.AuthorId   = user.Id;
+        comment.CreatedAt  = DateTime.UtcNow;
+
+        if (!Db.Create(comment)) return StatusCode(500, "Failed to add comment.");
+
+        Db.Create(new TicketTimelineEvent
+        {
+            TicketId    = comment.TicketId,
+            EventType   = (Int32)TimelineEventType.CommentAdded,
+            Description = $"Comment added by {user.Name}.",
+            ActorType   = (Int32)TimelineActorType.Human,
+            ActorId     = user.Id,
+            CreatedAt   = DateTime.UtcNow
+        });
+
+        ticket.UpdatedAt = DateTime.UtcNow;
+        Db.Update(ticket);
+
+        return comment;
+    }
+
+    [HttpGet(nameof(GetTicketDetail))]
+    public ActionResult<Object> GetTicketDetail(Int64 id, Token authToken)
+    {
+        var user = Db.GetSession(authToken)?.User;
+        if (user is null || user.UserType != 2) return Unauthorized();
+
+        var ticket = Db.GetTicketById(id);
+        if (ticket is null) return NotFound();
+
+        return new
+        {
+            ticket,
+            comments  = Db.GetCommentsForTicket(id),
+            diagnosis = Db.GetDiagnosisForTicket(id),
+            timeline  = Db.GetTimelineForTicket(id)
+        };
+    }
+
 }
 
 

csharp/App/Backend/DataTypes/Ticket.cs

@@ -0,0 +1,30 @@
+using SQLite;
+
+namespace InnovEnergy.App.Backend.DataTypes;
+
+public enum TicketStatus   { Open = 0, InProgress = 1, Escalated = 2, Resolved = 3, Closed = 4 }
+public enum TicketPriority { Critical = 0, High = 1, Medium = 2, Low = 3 }
+public enum TicketCategory { Hardware = 0, Software = 1, DataApi = 2, UserAccess = 3 }
+public enum TicketSource   { Manual = 0, AutoAlert = 1, Email = 2, Api = 3 }
+
+public class Ticket
+{
+    [PrimaryKey, AutoIncrement] public Int64 Id              { get; set; }
+
+    public String   Subject         { get; set; } = "";
+    public String   Description     { get; set; } = "";
+
+    [Indexed] public Int32 Status   { get; set; } = (Int32)TicketStatus.Open;
+    public Int32    Priority        { get; set; } = (Int32)TicketPriority.Medium;
+    public Int32    Category        { get; set; } = (Int32)TicketCategory.Hardware;
+    public Int32    Source          { get; set; } = (Int32)TicketSource.Manual;
+
+    [Indexed] public Int64  InstallationId  { get; set; }
+    public          Int64?  AssigneeId      { get; set; }
+    [Indexed] public Int64  CreatedByUserId { get; set; }
+
+    public String   Tags            { get; set; } = "";
+    public DateTime CreatedAt       { get; set; } = DateTime.UtcNow;
+    public DateTime UpdatedAt       { get; set; } = DateTime.UtcNow;
+    public DateTime? ResolvedAt     { get; set; }
+}

csharp/App/Backend/DataTypes/TicketAiDiagnosis.cs

@@ -0,0 +1,22 @@
+using SQLite;
+
+namespace InnovEnergy.App.Backend.DataTypes;
+
+public enum DiagnosisStatus   { Pending = 0, Analyzing = 1, Completed = 2, Failed = 3 }
+public enum DiagnosisFeedback { Accepted = 0, Rejected = 1, Overridden = 2 }
+
+public class TicketAiDiagnosis
+{
+    [PrimaryKey, AutoIncrement] public Int64 Id { get; set; }
+
+    [Indexed] public Int64   TicketId            { get; set; }
+    public          Int32    Status              { get; set; } = (Int32)DiagnosisStatus.Pending;
+    public          String?  RootCause           { get; set; }
+    public          Double?  Confidence          { get; set; }
+    public          String?  RecommendedActions  { get; set; }  // JSON array string
+    public          String?  SimilarTicketIds    { get; set; }  // comma-separated
+    public          Int32?   Feedback            { get; set; }  // null = no feedback yet
+    public          String?  OverrideText        { get; set; }
+    public          DateTime CreatedAt           { get; set; } = DateTime.UtcNow;
+    public          DateTime? CompletedAt        { get; set; }
+}

csharp/App/Backend/DataTypes/TicketComment.cs

@@ -0,0 +1,16 @@
+using SQLite;
+
+namespace InnovEnergy.App.Backend.DataTypes;
+
+public enum CommentAuthorType { Human = 0, AiAgent = 1 }
+
+public class TicketComment
+{
+    [PrimaryKey, AutoIncrement] public Int64 Id { get; set; }
+
+    [Indexed] public Int64  TicketId    { get; set; }
+    public          Int32   AuthorType  { get; set; } = (Int32)CommentAuthorType.Human;
+    public          Int64?  AuthorId    { get; set; }
+    public          String  Body        { get; set; } = "";
+    public          DateTime CreatedAt  { get; set; } = DateTime.UtcNow;
+}

csharp/App/Backend/DataTypes/TicketTimelineEvent.cs

@@ -0,0 +1,23 @@
+using SQLite;
+
+namespace InnovEnergy.App.Backend.DataTypes;
+
+public enum TimelineEventType
+{
+    Created = 0, StatusChanged = 1, Assigned = 2,
+    CommentAdded = 3, AiDiagnosisAttached = 4, Escalated = 5
+}
+
+public enum TimelineActorType { System = 0, AiAgent = 1, Human = 2 }
+
+public class TicketTimelineEvent
+{
+    [PrimaryKey, AutoIncrement] public Int64 Id { get; set; }
+
+    [Indexed] public Int64   TicketId    { get; set; }
+    public          Int32    EventType   { get; set; }
+    public          String   Description { get; set; } = "";
+    public          Int32    ActorType   { get; set; } = (Int32)TimelineActorType.System;
+    public          Int64?   ActorId     { get; set; }
+    public          DateTime CreatedAt   { get; set; } = DateTime.UtcNow;
+}

csharp/App/Backend/Database/Create.cs

@@ -74,6 +74,12 @@ public static partial class Db
     public static Boolean Create(DailyEnergyRecord record)    => Insert(record);
     public static Boolean Create(HourlyEnergyRecord record)   => Insert(record);
     public static Boolean Create(AiInsightCache cache)        => Insert(cache);
+
+    // Ticket system
+    public static Boolean Create(Ticket ticket)                => Insert(ticket);
+    public static Boolean Create(TicketComment comment)        => Insert(comment);
+    public static Boolean Create(TicketAiDiagnosis diagnosis)  => Insert(diagnosis);
+    public static Boolean Create(TicketTimelineEvent ev)       => Insert(ev);
     
     public static void HandleAction(UserAction newAction)
     {

csharp/App/Backend/Database/Db.cs

@@ -32,6 +32,12 @@ public static partial class Db
     public static TableQuery<HourlyEnergyRecord>   HourlyRecords     => Connection.Table<HourlyEnergyRecord>();
     public static TableQuery<AiInsightCache>       AiInsightCaches   => Connection.Table<AiInsightCache>();
 
+    // Ticket system tables
+    public static TableQuery<Ticket>              Tickets              => Connection.Table<Ticket>();
+    public static TableQuery<TicketComment>       TicketComments       => Connection.Table<TicketComment>();
+    public static TableQuery<TicketAiDiagnosis>   TicketAiDiagnoses    => Connection.Table<TicketAiDiagnosis>();
+    public static TableQuery<TicketTimelineEvent> TicketTimelineEvents => Connection.Table<TicketTimelineEvent>();
+
 
     public static void Init()
     {
@@ -63,6 +69,12 @@ public static partial class Db
             Connection.CreateTable<DailyEnergyRecord>();
             Connection.CreateTable<HourlyEnergyRecord>();
             Connection.CreateTable<AiInsightCache>();
+
+            // Ticket system tables
+            Connection.CreateTable<Ticket>();
+            Connection.CreateTable<TicketComment>();
+            Connection.CreateTable<TicketAiDiagnosis>();
+            Connection.CreateTable<TicketTimelineEvent>();
         });
         
         // One-time migration: normalize legacy long-form language values to ISO codes
@@ -112,6 +124,12 @@ public static partial class Db
         fileConnection.CreateTable<HourlyEnergyRecord>();
         fileConnection.CreateTable<AiInsightCache>();
 
+        // Ticket system tables
+        fileConnection.CreateTable<Ticket>();
+        fileConnection.CreateTable<TicketComment>();
+        fileConnection.CreateTable<TicketAiDiagnosis>();
+        fileConnection.CreateTable<TicketTimelineEvent>();
+
         return fileConnection;
         //return CopyDbToMemory(fileConnection);
     }

csharp/App/Backend/Database/Delete.cs

@@ -124,6 +124,17 @@ public static partial class Db
             Warnings      .Delete(w => w.InstallationId == installation.Id);
             UserActions   .Delete(a => a.InstallationId == installation.Id);
 
+            // Clean up tickets and their children for this installation
+            var ticketIds = Tickets.Where(t => t.InstallationId == installation.Id)
+                                   .Select(t => t.Id).ToList();
+            foreach (var tid in ticketIds)
+            {
+                TicketComments      .Delete(c => c.TicketId == tid);
+                TicketAiDiagnoses   .Delete(d => d.TicketId == tid);
+                TicketTimelineEvents.Delete(e => e.TicketId == tid);
+            }
+            Tickets.Delete(t => t.InstallationId == installation.Id);
+
             return Installations.Delete(i => i.Id == installation.Id) > 0;
         }
     }
@@ -199,6 +210,21 @@ public static partial class Db
         if (count > 0) Backup();
     }
 
+    public static Boolean Delete(Ticket ticket)
+    {
+        var deleteSuccess = RunTransaction(DeleteTicketAndChildren);
+        if (deleteSuccess) Backup();
+        return deleteSuccess;
+
+        Boolean DeleteTicketAndChildren()
+        {
+            TicketComments      .Delete(c => c.TicketId == ticket.Id);
+            TicketAiDiagnoses   .Delete(d => d.TicketId == ticket.Id);
+            TicketTimelineEvents.Delete(e => e.TicketId == ticket.Id);
+            return Tickets.Delete(t => t.Id == ticket.Id) > 0;
+        }
+    }
+
     /// <summary>
     /// Deletes all report records older than 1 year. Called annually on Jan 2
     /// after yearly reports are created. Uses fetch-then-delete for string-compared

csharp/App/Backend/Database/Read.cs

@@ -156,4 +156,33 @@ public static partial class Db
                               && c.ReportId   == reportId
                               && c.Language   == language)
             ?.InsightText;
+
+    // ── Ticket Queries ──────────────────────────────────────────────────
+
+    public static Ticket? GetTicketById(Int64 id)
+        => Tickets.FirstOrDefault(t => t.Id == id);
+
+    public static List<Ticket> GetAllTickets()
+        => Tickets.OrderByDescending(t => t.UpdatedAt).ToList();
+
+    public static List<Ticket> GetTicketsForInstallation(Int64 installationId)
+        => Tickets
+            .Where(t => t.InstallationId == installationId)
+            .OrderByDescending(t => t.CreatedAt)
+            .ToList();
+
+    public static List<TicketComment> GetCommentsForTicket(Int64 ticketId)
+        => TicketComments
+            .Where(c => c.TicketId == ticketId)
+            .OrderBy(c => c.CreatedAt)
+            .ToList();
+
+    public static TicketAiDiagnosis? GetDiagnosisForTicket(Int64 ticketId)
+        => TicketAiDiagnoses.FirstOrDefault(d => d.TicketId == ticketId);
+
+    public static List<TicketTimelineEvent> GetTimelineForTicket(Int64 ticketId)
+        => TicketTimelineEvents
+            .Where(e => e.TicketId == ticketId)
+            .OrderBy(e => e.CreatedAt)
+            .ToList();
 }

csharp/App/Backend/Database/Update.cs

@@ -49,11 +49,14 @@ public static partial class Db
     public static void UpdateAction(UserAction updatedAction)
     {
         var existingAction = UserActions.FirstOrDefault(action => action.Id == updatedAction.Id);
-        
+
         if (existingAction != null)
         {
             Update(updatedAction);
         }
     }
 
+    // Ticket system
+    public static Boolean Update(Ticket ticket)              => Update(obj: ticket);
+    public static Boolean Update(TicketAiDiagnosis diagnosis) => Update(obj: diagnosis);
 }

csharp/App/Backend/Program.cs

@@ -27,6 +27,7 @@ public static class Program
         Db.Init();
         LoadEnvFile();
         DiagnosticService.Initialize();
+        TicketDiagnosticService.Initialize();
         AlarmReviewService.StartDailyScheduler();
         // DailyIngestionService.StartScheduler();    // Phase 2: enable when S3 auto-push is ready
         // ReportAggregationService.StartScheduler(); // Phase 2: enable when scheduler should auto-run monthly/yearly

csharp/App/Backend/Services/TicketDiagnosticService.cs

@@ -0,0 +1,198 @@
+using Flurl.Http;
+using InnovEnergy.App.Backend.Database;
+using InnovEnergy.App.Backend.DataTypes;
+using Newtonsoft.Json;
+
+namespace InnovEnergy.App.Backend.Services;
+
+/// <summary>
+/// Generates AI-powered diagnoses for support tickets.
+/// Runs async after ticket creation; stores result in TicketAiDiagnosis table.
+/// </summary>
+public static class TicketDiagnosticService
+{
+    private static string _apiKey = "";
+    private static readonly string MistralUrl = "https://api.mistral.ai/v1/chat/completions";
+
+    public static void Initialize()
+    {
+        var apiKey = Environment.GetEnvironmentVariable("MISTRAL_API_KEY");
+        if (string.IsNullOrWhiteSpace(apiKey))
+            Console.Error.WriteLine("[TicketDiagnosticService] MISTRAL_API_KEY not set – ticket AI disabled.");
+        else
+            _apiKey = apiKey;
+
+        Console.WriteLine("[TicketDiagnosticService] initialised.");
+    }
+
+    public static bool IsEnabled => !string.IsNullOrEmpty(_apiKey);
+
+    /// <summary>
+    /// Called fire-and-forget after ticket creation.
+    /// Creates a TicketAiDiagnosis row (Pending → Analyzing → Completed | Failed).
+    /// </summary>
+    public static async Task DiagnoseTicketAsync(Int64 ticketId)
+    {
+        var ticket = Db.GetTicketById(ticketId);
+        if (ticket is null) return;
+
+        var installation = Db.GetInstallationById(ticket.InstallationId);
+        if (installation is null) return;
+
+        var diagnosis = new TicketAiDiagnosis
+        {
+            TicketId  = ticketId,
+            Status    = (Int32)DiagnosisStatus.Pending,
+            CreatedAt = DateTime.UtcNow
+        };
+        Db.Create(diagnosis);
+
+        if (!IsEnabled)
+        {
+            diagnosis.Status = (Int32)DiagnosisStatus.Failed;
+            Db.Update(diagnosis);
+            return;
+        }
+
+        diagnosis.Status = (Int32)DiagnosisStatus.Analyzing;
+        Db.Update(diagnosis);
+
+        try
+        {
+            var productName = ((ProductType)installation.Product).ToString();
+
+            var recentErrors = Db.Errors
+                .Where(e => e.InstallationId == ticket.InstallationId)
+                .OrderByDescending(e => e.Date)
+                .ToList()
+                .Select(e => e.Description)
+                .Distinct()
+                .Take(5)
+                .ToList();
+
+            var prompt = BuildPrompt(ticket, productName, recentErrors);
+            var result = await CallMistralAsync(prompt);
+
+            if (result is null)
+            {
+                diagnosis.Status = (Int32)DiagnosisStatus.Failed;
+            }
+            else
+            {
+                diagnosis.Status             = (Int32)DiagnosisStatus.Completed;
+                diagnosis.RootCause          = result.RootCause;
+                diagnosis.Confidence         = result.Confidence;
+                diagnosis.RecommendedActions = result.RecommendedActionsJson;
+                diagnosis.CompletedAt        = DateTime.UtcNow;
+            }
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[TicketDiagnosticService] {ex.Message}");
+            diagnosis.Status = (Int32)DiagnosisStatus.Failed;
+        }
+
+        Db.Update(diagnosis);
+
+        Db.Create(new TicketTimelineEvent
+        {
+            TicketId    = ticketId,
+            EventType   = (Int32)TimelineEventType.AiDiagnosisAttached,
+            Description = diagnosis.Status == (Int32)DiagnosisStatus.Completed
+                ? "AI diagnosis completed."
+                : "AI diagnosis failed.",
+            ActorType   = (Int32)TimelineActorType.AiAgent,
+            CreatedAt   = DateTime.UtcNow
+        });
+    }
+
+    private static string BuildPrompt(Ticket ticket, string productName, List<string> recentErrors)
+    {
+        var recentList = recentErrors.Count > 0
+            ? string.Join(", ", recentErrors)
+            : "none";
+
+        return $@"You are a senior field technician for {productName} battery energy storage systems.
+A support ticket has been submitted with the following details:
+Subject: {ticket.Subject}
+Description: {ticket.Description}
+Category: {(TicketCategory)ticket.Category}
+Priority: {(TicketPriority)ticket.Priority}
+Recent system alarms: {recentList}
+
+Analyze this ticket and respond in JSON only — no markdown, no explanation outside JSON:
+{{
+  ""rootCause"": ""One concise sentence describing the most likely root cause."",
+  ""confidence"": 0.85,
+  ""recommendedActions"": [""Action 1"", ""Action 2"", ""Action 3""]
+}}
+Confidence must be a number between 0.0 and 1.0.";
+    }
+
+    private static async Task<TicketDiagnosisResult?> CallMistralAsync(string prompt)
+    {
+        try
+        {
+            var body = new
+            {
+                model       = "mistral-small-latest",
+                messages    = new[] { new { role = "user", content = prompt } },
+                max_tokens  = 300,
+                temperature = 0.2
+            };
+
+            var text = await MistralUrl
+                .WithHeader("Authorization", $"Bearer {_apiKey}")
+                .PostJsonAsync(body)
+                .ReceiveString();
+
+            var envelope = JsonConvert.DeserializeObject<dynamic>(text);
+            var content  = (string?)envelope?.choices?[0]?.message?.content;
+
+            if (string.IsNullOrWhiteSpace(content)) return null;
+
+            var json = content.Trim();
+            if (json.StartsWith("```"))
+            {
+                var nl = json.IndexOf('\n');
+                if (nl >= 0) json = json[(nl + 1)..];
+                if (json.EndsWith("```")) json = json[..^3];
+                json = json.Trim();
+            }
+
+            var parsed = JsonConvert.DeserializeObject<TicketDiagnosisRaw>(json);
+            if (parsed is null) return null;
+
+            return new TicketDiagnosisResult
+            {
+                RootCause            = parsed.RootCause,
+                Confidence           = parsed.Confidence,
+                RecommendedActionsJson = JsonConvert.SerializeObject(parsed.RecommendedActions ?? Array.Empty<string>())
+            };
+        }
+        catch (Exception ex)
+        {
+            Console.Error.WriteLine($"[TicketDiagnosticService] HTTP error: {ex.Message}");
+            return null;
+        }
+    }
+}
+
+internal class TicketDiagnosisRaw
+{
+    [JsonProperty("rootCause")]
+    public String? RootCause { get; set; }
+
+    [JsonProperty("confidence")]
+    public Double? Confidence { get; set; }
+
+    [JsonProperty("recommendedActions")]
+    public String[]? RecommendedActions { get; set; }
+}
+
+internal class TicketDiagnosisResult
+{
+    public String?  RootCause              { get; set; }
+    public Double?  Confidence             { get; set; }
+    public String?  RecommendedActionsJson { get; set; }
+}