using System.Diagnostics;
using System.Security.Cryptography;
using System.Text;
using System.Text.Json;
using PlotLine.Data;
using PlotLine.Models;
using PlotLine.ViewModels;

namespace PlotLine.Services;

public interface IStoryIntelligenceVisualisationSnapshotService
{
    Task<StoryIntelligenceExperiencePrototypeViewModel?> BuildSnapshotAsync(int runId, int userId);
    Task<StoryIntelligenceExperiencePrototypeViewModel?> BuildImportSessionSnapshotAsync(int importSessionId, int userId);
    Task<IReadOnlyList<StoryIntelligenceExperienceRunOption>> ListRunOptionsAsync(int userId);
    Task<IReadOnlyList<StoryIntelligenceExperienceRunOption>> ListImportSessionOptionsAsync(int userId);
}

public sealed class StoryIntelligenceVisualisationSnapshotService(
    IStoryIntelligenceResultRepository repository,
    IStoryIntelligencePipelineRepository pipelines,
    IStoryIntelligenceSourceRepository sources,
    IIllustrationLibraryService illustrationLibrary,
    ILogger<StoryIntelligenceVisualisationSnapshotService> logger) : IStoryIntelligenceVisualisationSnapshotService
{
    private const string FallbackRoot = "/images/story-intelligence/prototype";
    private static readonly JsonSerializerOptions JsonOptions = new()
    {
        PropertyNamingPolicy = JsonNamingPolicy.CamelCase,
        PropertyNameCaseInsensitive = true
    };

    public async Task<IReadOnlyList<StoryIntelligenceExperienceRunOption>> ListRunOptionsAsync(int userId)
    {
        var runs = await repository.ListRunsAsync();
        return runs
            .Where(run => run.UserID == userId)
            .OrderByDescending(run => run.CreatedUtc)
            .Take(12)
            .Select(run => new StoryIntelligenceExperienceRunOption
            {
                RunId = run.StoryIntelligenceRunID,
                Status = run.Status,
                CreatedUtc = run.CreatedUtc,
                Label = $"{DisplayTitle(run.ProjectTitle, "Project")} / {DisplayTitle(run.BookTitle, "Book")} - {run.Status} - {run.CreatedUtc:u}"
            })
            .ToList();
    }

    public async Task<IReadOnlyList<StoryIntelligenceExperienceRunOption>> ListImportSessionOptionsAsync(int userId)
    {
        await EnsureActiveImportSessionsAsync(userId);
        var sessions = await pipelines.ListForUserAsync(userId);
        return sessions
            .OrderByDescending(session => session.UpdatedUtc)
            .Take(12)
            .Select(session => new StoryIntelligenceExperienceRunOption
            {
                ImportSessionId = session.StoryIntelligenceBookPipelineID,
                RunId = session.LastRunID ?? 0,
                Status = session.Status,
                CreatedUtc = session.CreatedUtc,
                Label = $"{DisplayTitle(session.ProjectName, "Project")} / {DisplayTitle(session.BookDisplayTitle, "Book")} - {session.Status} - started {session.CreatedUtc:u}"
            })
            .ToList();
    }

    private async Task EnsureActiveImportSessionsAsync(int userId)
    {
        var runs = await repository.ListRunsAsync();
        var activeBookRuns = runs
            .Where(run => run.UserID == userId
                && run.ProjectID.HasValue
                && run.BookID.HasValue
                && !IsTerminal(run.Status))
            .GroupBy(run => new { ProjectID = run.ProjectID!.Value, BookID = run.BookID!.Value })
            .Select(group => group.OrderByDescending(run => run.CreatedUtc).First())
            .ToList();

        foreach (var run in activeBookRuns)
        {
            await pipelines.UpsertAsync(new StoryIntelligenceBookPipelineSaveRequest
            {
                ProjectID = run.ProjectID!.Value,
                BookID = run.BookID!.Value,
                CurrentStage = StoryIntelligencePipelineStages.Chapters,
                LastCompletedStage = null,
                CurrentReviewStage = null,
                Status = StoryIntelligencePipelineStatuses.InProgress,
                CompletedUtc = null,
                LastRunID = run.StoryIntelligenceRunID
            });
        }
    }

    public async Task<StoryIntelligenceExperiencePrototypeViewModel?> BuildSnapshotAsync(int runId, int userId)
    {
        var stopwatch = Stopwatch.StartNew();
        var run = await repository.GetRunAsync(runId);
        if (run is null || run.UserID != userId)
        {
            return null;
        }

        var results = (await repository.ListSceneResultsAsync(runId)).ToList();
        var parsed = results
            .Select(result => ReadSceneResult(runId, result))
            .OrderBy(item => SceneSortChapter(item))
            .ThenBy(item => SceneSortNumber(item))
            .ThenBy(item => item.Result.SceneResultID)
            .ToList();
        var completed = parsed
            .Where(item => item.Scene is not null)
            .ToList();

        var current = PickCurrentScene(run, completed);
        var scenes = BuildSceneStates(run, parsed, completed, current).ToList();
        if (scenes.Count == 0)
        {
            scenes.Add(BuildEmptyScene(run));
        }

        var model = new StoryIntelligenceExperiencePrototypeViewModel
        {
            Mode = "real",
            RunId = run.StoryIntelligenceRunID,
            RunStatus = run.Status,
            GeneratedUtc = DateTime.UtcNow,
            ChangeToken = ChangeToken(run, results),
            IsTerminal = IsTerminal(run.Status),
            SnapshotMessage = SnapshotMessage(run, completed.Count),
            Diagnostics = BuildDiagnostics(run, results, parsed, completed, current),
            ProjectName = DisplayTitle(run.ProjectTitle, "Untitled project"),
            BookTitle = DisplayTitle(run.BookTitle, "Untitled book"),
            Scenes = scenes
        };

        await illustrationLibrary.ApplyApprovedIllustrationsAsync(model);
        logger.LogInformation("Built Story Intelligence visualisation snapshot for run {RunId} in {ElapsedMs}ms.", runId, stopwatch.ElapsedMilliseconds);
        return model;
    }

    public async Task<StoryIntelligenceExperiencePrototypeViewModel?> BuildImportSessionSnapshotAsync(int importSessionId, int userId)
    {
        var stopwatch = Stopwatch.StartNew();
        var session = await pipelines.GetByIdForUserAsync(importSessionId, userId);
        if (session is null)
        {
            return null;
        }

        var runs = (await repository.ListRunsByBookForUserAsync(session.BookID, userId))
            .OrderBy(run => run.ChapterNumber ?? decimal.MaxValue)
            .ThenBy(run => run.ChapterID ?? int.MaxValue)
            .ThenBy(run => run.StoryIntelligenceRunID)
            .ToList();
        if (runs.Count == 0)
        {
            return null;
        }

        var runSnapshots = new List<RunSnapshot>();
        foreach (var run in runs)
        {
            var results = (await repository.ListSceneResultsAsync(run.StoryIntelligenceRunID)).ToList();
            var parsed = results
                .Select(result => ReadSceneResult(run.StoryIntelligenceRunID, result))
                .OrderBy(item => SceneSortChapter(item))
                .ThenBy(item => SceneSortNumber(item))
                .ThenBy(item => item.Result.SceneResultID)
                .ToList();
            var completed = parsed.Where(item => item.Scene is not null).ToList();
            runSnapshots.Add(new(run, results, parsed, completed, PickCurrentScene(run, completed)));
        }

        var activeSnapshot = PickActiveRunSnapshot(runSnapshots) ?? runSnapshots.Last();
        var current = activeSnapshot.Current ?? runSnapshots.LastOrDefault(snapshot => snapshot.Completed.Count > 0)?.Current;
        var totalPersistedResults = runSnapshots.Sum(snapshot => snapshot.Results.Count);
        var parsedScenes = runSnapshots.Sum(snapshot => snapshot.Completed.Count);
        var totalScenes = Math.Max(
            runSnapshots.Sum(snapshot => Math.Max(snapshot.Run.TotalDetectedScenes ?? 0, snapshot.Results.Count)),
            parsedScenes);
        var sourceChapterCount = (await sources.ListChaptersAsync(session.BookID)).Count;
        var bookChapterTotal = Math.Max(1, Math.Max(sourceChapterCount, runSnapshots.Count));
        var overallProgressPercent = BookProgress(runSnapshots, bookChapterTotal, isTerminal: false);
        var completedChapterRuns = runSnapshots.Count(snapshot => IsTerminal(snapshot.Run.Status));
        var isTerminal = runSnapshots.All(snapshot => IsTerminal(snapshot.Run.Status))
            && string.Equals(session.Status, StoryIntelligencePipelineStatuses.Complete, StringComparison.OrdinalIgnoreCase);
        overallProgressPercent = BookProgress(runSnapshots, bookChapterTotal, isTerminal);
        var scenes = new List<StoryIntelligenceExperienceSceneState>();
        var nextSceneNumber = 1;
        foreach (var snapshot in runSnapshots)
        {
            var runScenes = BuildSceneStates(
                    snapshot.Run,
                    snapshot.Parsed,
                    snapshot.Completed,
                    current,
                    continuousSceneNumberStart: nextSceneNumber,
                    overallCompletedScenes: parsedScenes,
                    overallTotalScenes: totalScenes,
                    overallChaptersAnalysed: completedChapterRuns,
                    overallChapterTotal: bookChapterTotal,
                    overallProgressPercent: overallProgressPercent,
                    overallStage: OverallStage(session, activeSnapshot.Run),
                    overallRemaining: EstimateSessionRemaining(runSnapshots, parsedScenes, totalScenes),
                    continuousSceneNumbering: true,
                    overallTerminal: isTerminal)
                .ToList();
            scenes.AddRange(runScenes);
            nextSceneNumber += snapshot.Completed.Count;
        }

        if (scenes.Count == 0)
        {
            scenes.Add(BuildEmptyScene(activeSnapshot.Run));
        }

        var model = new StoryIntelligenceExperiencePrototypeViewModel
        {
            Mode = "real",
            ImportSessionId = session.StoryIntelligenceBookPipelineID,
            RunId = activeSnapshot.Run.StoryIntelligenceRunID,
            RunStatus = SessionStatus(session, runSnapshots),
            GeneratedUtc = DateTime.UtcNow,
            ChangeToken = SessionChangeToken(session, runSnapshots),
            IsTerminal = isTerminal,
            SnapshotMessage = SessionSnapshotMessage(session, runSnapshots),
            Diagnostics = BuildSessionDiagnostics(session, runSnapshots, activeSnapshot, current, parsedScenes, totalPersistedResults, overallProgressPercent),
            ProjectName = DisplayTitle(session.ProjectName, "Untitled project"),
            BookTitle = DisplayTitle(session.BookDisplayTitle, "Untitled book"),
            Scenes = scenes
        };

        await illustrationLibrary.ApplyApprovedIllustrationsAsync(model);
        logger.LogInformation("Built Story Intelligence import session visualisation snapshot for session {ImportSessionId} in {ElapsedMs}ms.", importSessionId, stopwatch.ElapsedMilliseconds);
        return model;
    }

    private static IEnumerable<StoryIntelligenceExperienceSceneState> BuildSceneStates(
        StoryIntelligenceSavedRun run,
        IReadOnlyList<ParsedSceneResult> allResults,
        IReadOnlyList<ParsedSceneResult> completed,
        ParsedSceneResult? current,
        int continuousSceneNumberStart = 1,
        int? overallCompletedScenes = null,
        int? overallTotalScenes = null,
        int? overallChaptersAnalysed = null,
        int? overallChapterTotal = null,
        int? overallProgressPercent = null,
        string? overallStage = null,
        string? overallRemaining = null,
        bool continuousSceneNumbering = false,
        bool overallTerminal = false)
    {
        var totalScenes = Math.Max(run.TotalDetectedScenes ?? 0, allResults.Count);
        var completedScenes = run.CompletedScenes ?? completed.Count;
        var displayIndex = 0;
        foreach (var item in completed)
        {
            var scene = item.Scene!;
            var sourceSceneNumber = SceneNumber(item);
            var sceneNumber = continuousSceneNumbering ? continuousSceneNumberStart + displayIndex++ : sourceSceneNumber;
            var isCurrent = current?.Result.SceneResultID == item.Result.SceneResultID;
            yield return new StoryIntelligenceExperienceSceneState
            {
                Id = $"scene-result-{item.Result.SceneResultID}",
                SceneNumber = sceneNumber,
                Title = SceneTitle(scene, item.Result, sceneNumber),
                Summary = Trim(FirstConfigured(scene.Summary?.Short, scene.Summary?.Detailed, run.CurrentMessage, "Scene analysed."), 180),
                Stage = overallStage ?? StageDisplay(run),
                TimelineLabel = TimelineLabel(scene, item.Result),
                TimelineEvent = Trim(FirstConfigured(scene.Summary?.Short, scene.ScenePurpose?.ObservedFunction, "Scene analysed"), 42),
                ProgressPercent = overallProgressPercent
                    ?? (overallTotalScenes.HasValue
                    ? OverallProgress(overallCompletedScenes ?? completedScenes, overallTotalScenes.Value, overallTerminal)
                    : Progress(run, completedScenes, totalScenes)),
                ChaptersAnalysed = overallChaptersAnalysed ?? ChapterCount(completed),
                ChapterTotal = Math.Max(1, overallChapterTotal ?? run.SourceChapterCount ?? ChapterCount(completed)),
                ScenesAnalysed = overallCompletedScenes ?? completedScenes,
                SceneTotal = Math.Max(1, overallTotalScenes ?? totalScenes),
                EstimatedRemaining = overallRemaining ?? EstimateRemaining(run, completedScenes, totalScenes),
                PovCharacterId = CharacterId(scene.PointOfView?.CharacterName),
                Location = BuildLocation(scene),
                Characters = BuildCharacters(scene),
                Assets = BuildAssets(scene),
                Relationships = BuildRelationships(scene),
                KnowledgeThreads = BuildKnowledge(scene),
                Observations = BuildObservations(scene),
                LatestDiscoveries = isCurrent ? BuildDiscoveries(scene).ToList() : [],
                ActivityFeed = isCurrent ? BuildActivity(run, sceneNumber).ToList() : []
            };
        }
    }

    private static StoryIntelligenceExperienceSceneState BuildEmptyScene(StoryIntelligenceSavedRun run)
        => new()
        {
            Id = $"run-{run.StoryIntelligenceRunID}-waiting",
            SceneNumber = 1,
            Title = run.Status is StoryIntelligenceRunStatuses.Failed ? "Analysis failed" : "Waiting for analysed scenes",
            Summary = FirstConfigured(run.ErrorMessage, run.CurrentMessage, "No scene analysis results have been persisted yet."),
            Stage = StageDisplay(run),
            TimelineLabel = "Pending",
            TimelineEvent = "No scene snapshot yet",
            ProgressPercent = Progress(run, run.CompletedScenes ?? 0, run.TotalDetectedScenes ?? 0),
            ChaptersAnalysed = 0,
            ChapterTotal = Math.Max(1, run.SourceChapterCount ?? 1),
            ScenesAnalysed = run.CompletedScenes ?? 0,
            SceneTotal = Math.Max(1, run.TotalDetectedScenes ?? 1),
            EstimatedRemaining = EstimateRemaining(run, run.CompletedScenes ?? 0, run.TotalDetectedScenes ?? 0),
            Location = PendingLocation(),
            LatestDiscoveries = run.ErrorMessage is null ? [] : [$"Run failed: {Trim(run.ErrorMessage, 90)}"],
            ActivityFeed = BuildActivity(run, null).ToList()
        };

    private static ParsedSceneResult? PickCurrentScene(StoryIntelligenceSavedRun run, IReadOnlyList<ParsedSceneResult> completed)
    {
        if (completed.Count == 0)
        {
            return null;
        }

        return completed.Last();
    }

    private static IReadOnlyList<StoryIntelligenceExperienceCharacterState> BuildCharacters(SceneIntelligenceScene scene)
    {
        var povName = Clean(scene.PointOfView?.CharacterName);
        var states = new List<StoryIntelligenceExperienceCharacterState>();
        var reservedCodes = new HashSet<string>(StringComparer.OrdinalIgnoreCase);
        foreach (var group in (scene.Characters ?? [])
                     .Where(character => !string.IsNullOrWhiteSpace(character.Name))
                     .GroupBy(character => Clean(character.Name), StringComparer.OrdinalIgnoreCase)
                     .Take(5))
        {
            var character = group.OrderByDescending(item => item.Confidence ?? 0).First();
            var isPov = !string.IsNullOrWhiteSpace(povName) && string.Equals(group.Key, povName, StringComparison.OrdinalIgnoreCase);
            var libraryCode = CharacterLibraryCode(group.Key, character, scene, reservedCodes);
            reservedCodes.Add(libraryCode);
            states.Add(new StoryIntelligenceExperienceCharacterState
            {
                Id = CharacterId(group.Key),
                LibraryCode = libraryCode,
                Name = group.Key,
                Role = isPov ? "POV character" : FirstConfigured(character.RoleInScene, character.MentionedOnly == true ? "Referenced" : "Scene character"),
                Relevance = Trim(FirstConfigured(character.Notes, string.Join(", ", character.Actions ?? []), character.MentionedOnly == true ? "Mentioned only" : "Present"), 60),
                Weight = isPov ? 100 : CharacterWeight(character),
                ImagePath = CharacterFallback(group.Key)
            });
        }

        if (!string.IsNullOrWhiteSpace(povName) && states.All(character => !string.Equals(character.Name, povName, StringComparison.OrdinalIgnoreCase)))
        {
            var libraryCode = CharacterLibraryCode(povName, null, scene, reservedCodes);
            states.Insert(0, new StoryIntelligenceExperienceCharacterState
            {
                Id = CharacterId(povName),
                LibraryCode = libraryCode,
                Name = povName,
                Role = "POV character",
                Relevance = "Point of view",
                Weight = 100,
                ImagePath = CharacterFallback(povName)
            });
        }

        return states.OrderByDescending(character => character.Weight).ToList();
    }

    private static StoryIntelligenceExperienceLocationState BuildLocation(SceneIntelligenceScene scene)
    {
        var location = (scene.Locations ?? [])
            .Where(item => !string.IsNullOrWhiteSpace(item.Name) && item.MentionedOnly != true)
            .OrderByDescending(item => item.PresentInScene == true)
            .ThenByDescending(item => Specificity(item.Name))
            .ThenByDescending(item => item.Confidence ?? 0)
            .FirstOrDefault();

        var name = Clean(FirstConfigured(location?.Name, scene.Setting?.LocationName));
        if (string.IsNullOrWhiteSpace(name))
        {
            return PendingLocation();
        }

        return new StoryIntelligenceExperienceLocationState
        {
            Id = $"location-result-{StableKey(name)}",
            LibraryCode = LocationLibraryCode(name, location, scene.Setting),
            Name = name,
            Label = Trim(FirstConfigured(location?.ParentLocationHint, location?.LocationType, location?.GenericRoomType, scene.Setting?.ParentLocationHint, "Active scene location"), 44),
            ImagePath = LocationFallback(name)
        };
    }

    private static IReadOnlyList<StoryIntelligenceExperienceAssetState> BuildAssets(SceneIntelligenceScene scene)
        => (scene.Assets ?? [])
            .Where(asset => !string.IsNullOrWhiteSpace(asset.Name) && asset.MentionedOnly != true && !IsLowValueAsset(asset))
            .GroupBy(asset => Clean(asset.Name), StringComparer.OrdinalIgnoreCase)
            .Select(group =>
            {
                var asset = group.OrderByDescending(item => item.Confidence ?? 0).First();
                return new StoryIntelligenceExperienceAssetState
                {
                    Id = $"asset-result-{StableKey(group.Key)}",
                    LibraryCode = AssetLibraryCode(group.Key, asset),
                    Name = group.Key,
                    Label = Trim(FirstConfigured(asset.Status, asset.AssetType, asset.Notes, "Story asset"), 32),
                    Weight = AssetWeight(asset),
                    ImagePath = AssetFallback(group.Key)
                };
            })
            .OrderByDescending(asset => asset.Weight)
            .Take(5)
            .ToList();

    private static IReadOnlyList<StoryIntelligenceExperienceRelationshipState> BuildRelationships(SceneIntelligenceScene scene)
        => (scene.Relationships ?? [])
            .Where(item => !string.IsNullOrWhiteSpace(item.CharacterA) && !string.IsNullOrWhiteSpace(item.CharacterB))
            .Select(item => new StoryIntelligenceExperienceRelationshipState
            {
                Id = $"relationship-result-{StableKey(item.CharacterA!)}-{StableKey(item.CharacterB!)}-{StableKey(item.RelationshipSignal)}",
                SourceId = CharacterId(item.CharacterA),
                TargetId = CharacterId(item.CharacterB),
                Label = Trim(FirstConfigured(item.RelationshipSignal, "Relationship signal"), 44),
                State = Trim(FirstConfigured(item.Evidence, item.RelationshipSignal, "Emerging"), 58),
                Weight = ConfidenceWeight(item.Confidence, 70)
            })
            .OrderByDescending(item => item.Weight)
            .Take(4)
            .ToList();

    private static IReadOnlyList<StoryIntelligenceExperienceTextItem> BuildKnowledge(SceneIntelligenceScene scene)
    {
        var questions = (scene.QuestionsRaised ?? []).Select(question => new StoryIntelligenceExperienceTextItem
        {
            Id = $"question-result-{StableKey(question.Question)}",
            Title = Trim(FirstConfigured(question.Question, "Question raised"), 70),
            Detail = Trim(FirstConfigured(question.Evidence, question.Scope, "Open question"), 120),
            Tone = "question"
        });
        var knowledge = (scene.KnowledgeChanges ?? []).Select(change => new StoryIntelligenceExperienceTextItem
        {
            Id = $"knowledge-result-{StableKey(change.RecipientCharacter)}-{StableKey(change.KnowledgeItem)}",
            Title = Trim(FirstConfigured(change.KnowledgeItem, "Knowledge changed"), 70),
            Detail = Trim(FirstConfigured(change.Evidence, change.ChangeType, change.SourceType, "Knowledge update"), 120),
            Tone = "secret"
        });
        return questions.Concat(knowledge).Take(4).ToList();
    }

    private static IReadOnlyList<StoryIntelligenceExperienceTextItem> BuildObservations(SceneIntelligenceScene scene)
        => (scene.Observations ?? []).Select(observation => new StoryIntelligenceExperienceTextItem
            {
                Id = $"observation-result-{StableKey(observation.ObservationType)}-{StableKey(observation.SubjectName)}-{StableKey(observation.Predicate)}",
                Title = Trim(FirstConfigured(observation.Description, observation.Predicate, observation.ObservationType, "Story observation"), 74),
                Detail = Trim(FirstConfigured(observation.Evidence, $"{observation.SubjectName} {observation.Predicate} {observation.ObjectName}".Trim(), "Observed in current scene"), 128),
                Tone = "insight"
            })
            .Take(4)
            .ToList();

    private static IEnumerable<string> BuildDiscoveries(SceneIntelligenceScene scene)
    {
        foreach (var character in (scene.Characters ?? []).Where(item => !string.IsNullOrWhiteSpace(item.Name)).Take(2))
        {
            yield return $"Character found: {Clean(character.Name)}";
        }

        var location = FirstConfigured(scene.Locations?.FirstOrDefault(item => !string.IsNullOrWhiteSpace(item.Name))?.Name, scene.Setting?.LocationName);
        if (!string.IsNullOrWhiteSpace(location))
        {
            yield return $"Location found: {Clean(location)}";
        }

        foreach (var asset in (scene.Assets ?? []).Where(item => !string.IsNullOrWhiteSpace(item.Name) && !IsLowValueAsset(item)).Take(2))
        {
            yield return $"Asset found: {Clean(asset.Name)}";
        }
    }

    private static IEnumerable<string> BuildActivity(StoryIntelligenceSavedRun run, int? sceneNumber)
    {
        if (!string.IsNullOrWhiteSpace(run.CurrentMessage))
        {
            yield return run.CurrentMessage!;
        }

        if (sceneNumber.HasValue)
        {
            yield return $"Scene {sceneNumber:N0} snapshot loaded";
        }

        yield return $"Run status: {run.Status}";
    }

    private ParsedSceneResult ReadSceneResult(int runId, StoryIntelligenceSavedSceneResult result)
    {
        var scene = TryReadScene(result, out var error);
        if (scene is null)
        {
            logger.LogWarning(
                "Story Intelligence visualisation skipped unparseable scene result {SceneResultId} for run {RunId}: {ParseError}",
                result.SceneResultID,
                runId,
                error ?? "Parsed scene was empty or missing schema version.");
        }

        return new ParsedSceneResult(result, scene, error);
    }

    private static SceneIntelligenceScene? TryReadScene(StoryIntelligenceSavedSceneResult result, out string? safeError)
    {
        safeError = null;
        if (string.IsNullOrWhiteSpace(result.ParsedJson))
        {
            safeError = "Parsed JSON was empty.";
            return null;
        }

        try
        {
            var direct = JsonSerializer.Deserialize<SceneIntelligenceScene>(result.ParsedJson, JsonOptions);
            if (!string.IsNullOrWhiteSpace(direct?.SchemaVersion))
            {
                return direct;
            }

            using var document = JsonDocument.Parse(result.ParsedJson);
            if (document.RootElement.TryGetProperty("parsedScene", out var parsedScene))
            {
                return parsedScene.Deserialize<SceneIntelligenceScene>(JsonOptions);
            }
        }
        catch (JsonException ex)
        {
            safeError = ex.Message;
        }

        safeError ??= "Parsed JSON did not contain a scene payload.";
        return null;
    }

    private static string ChangeToken(StoryIntelligenceSavedRun run, IReadOnlyList<StoryIntelligenceSavedSceneResult> results)
    {
        var resultToken = string.Join(';', results
            .OrderBy(result => result.SceneResultID)
            .Select(result => string.Join('|',
                result.SceneResultID,
                result.ChapterID,
                result.SceneID,
                result.TemporarySceneNumber,
                result.ValidationErrorsCount,
                result.ValidationWarningsCount,
                result.InputTokens,
                result.OutputTokens,
                result.TotalTokens,
                result.DurationMs,
                result.CreatedUtc.ToUniversalTime().Ticks,
                StableContentHash(result.ParsedJson))));
        var raw = string.Join('|',
            run.StoryIntelligenceRunID,
            run.Status,
            run.CurrentStage,
            run.CurrentMessage,
            run.CompletedScenes,
            run.FailedScenes,
            run.TotalDetectedScenes,
            run.CompletedUtc?.ToUniversalTime().Ticks,
            run.UpdatedUtc.ToUniversalTime().Ticks,
            run.TotalInputTokens,
            run.TotalOutputTokens,
            run.TotalTokens,
            run.TotalDurationMs,
            run.ErrorMessage,
            run.ErrorDetail is null ? string.Empty : StableContentHash(run.ErrorDetail),
            results.Count,
            resultToken);
        return Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(raw)))[..16].ToLowerInvariant();
    }

    private static string SessionChangeToken(StoryIntelligenceBookPipelineState session, IReadOnlyList<RunSnapshot> snapshots)
    {
        var raw = string.Join('|',
            session.StoryIntelligenceBookPipelineID,
            session.Status,
            session.CurrentStage,
            session.LastCompletedStage,
            session.CurrentReviewStage,
            session.UpdatedUtc.ToUniversalTime().Ticks,
            string.Join("~", snapshots.Select(snapshot => ChangeToken(snapshot.Run, snapshot.Results))));
        return Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(raw)))[..16].ToLowerInvariant();
    }

    private static RunSnapshot? PickActiveRunSnapshot(IReadOnlyList<RunSnapshot> snapshots)
        => snapshots.FirstOrDefault(snapshot => !IsTerminal(snapshot.Run.Status))
           ?? snapshots.LastOrDefault(snapshot => snapshot.Completed.Count > 0)
           ?? snapshots.LastOrDefault();

    private static string OverallStage(StoryIntelligenceBookPipelineState session, StoryIntelligenceSavedRun activeRun)
    {
        if (!IsTerminal(activeRun.Status))
        {
            return FirstConfigured(activeRun.CurrentStage, activeRun.Status);
        }

        return session.CurrentStage switch
        {
            StoryIntelligencePipelineStages.Complete => "Ready for Review",
            StoryIntelligencePipelineStages.Chapters => "Reading Chapters",
            _ => session.CurrentStage
        };
    }

    private static string EstimateSessionRemaining(IReadOnlyList<RunSnapshot> snapshots, int completedScenes, int totalScenes)
    {
        if (totalScenes <= 0 || completedScenes <= 0)
        {
            return snapshots.All(snapshot => IsTerminal(snapshot.Run.Status)) ? "Ready to review" : "Calculating";
        }

        if (completedScenes >= totalScenes && snapshots.All(snapshot => IsTerminal(snapshot.Run.Status)))
        {
            return "Ready to review";
        }

        var elapsedMs = snapshots.Sum(snapshot => snapshot.Run.TotalDurationMs ?? Math.Max(0, Convert.ToInt64((DateTime.UtcNow - snapshot.Run.StartedUtc).TotalMilliseconds)));
        var averageMs = elapsedMs / Math.Max(1, completedScenes);
        return FormatDuration(averageMs * Math.Max(0, totalScenes - completedScenes));
    }

    private static string SessionStatus(StoryIntelligenceBookPipelineState session, IReadOnlyList<RunSnapshot> snapshots)
    {
        if (snapshots.Any(snapshot => !IsTerminal(snapshot.Run.Status)))
        {
            return StoryIntelligenceRunStatuses.Running;
        }

        return string.Equals(session.Status, StoryIntelligencePipelineStatuses.Complete, StringComparison.OrdinalIgnoreCase)
            ? StoryIntelligenceRunStatuses.Completed
            : StoryIntelligenceRunStatuses.CompletedWithWarnings;
    }

    private static string SessionSnapshotMessage(StoryIntelligenceBookPipelineState session, IReadOnlyList<RunSnapshot> snapshots)
    {
        var active = snapshots.FirstOrDefault(snapshot => !IsTerminal(snapshot.Run.Status));
        if (active is not null)
        {
            return FirstConfigured(active.Run.CurrentMessage, $"Analysing chapter {active.Run.ChapterNumber:0.##}.");
        }

        return string.Equals(session.Status, StoryIntelligencePipelineStatuses.Complete, StringComparison.OrdinalIgnoreCase)
            ? "Book analysis complete and ready for review."
            : "All known chapter runs are complete. Awaiting the next book import stage.";
    }

    private static string CurrentSceneText(RunSnapshot snapshot)
    {
        if (snapshot.Run.TotalDetectedScenes.HasValue)
        {
            var completed = Math.Clamp(snapshot.Run.CompletedScenes ?? snapshot.Completed.Count, 0, snapshot.Run.TotalDetectedScenes.Value);
            return $"Scene {completed:N0} of {snapshot.Run.TotalDetectedScenes.Value:N0}";
        }

        return snapshot.Current is null ? "Waiting" : $"Scene {SceneSortNumber(snapshot.Current):0.##}";
    }

    private static StoryIntelligenceExperienceSnapshotDiagnostics BuildSessionDiagnostics(
        StoryIntelligenceBookPipelineState session,
        IReadOnlyList<RunSnapshot> snapshots,
        RunSnapshot activeSnapshot,
        ParsedSceneResult? current,
        int parsedScenes,
        int totalPersistedResults,
        int overallProgressPercent)
    {
        var failed = snapshots.Sum(snapshot => snapshot.Parsed.Count(item => item.Scene is null));
        var warning = failed == 0 ? null : $"{failed:N0} scene result(s) skipped because they could not be parsed.";
        return new()
        {
            RequestedMode = "real",
            RequestedImportSessionId = session.StoryIntelligenceBookPipelineID,
            ResolvedImportSessionId = session.StoryIntelligenceBookPipelineID,
            ActiveChapterRunId = activeSnapshot.Run.StoryIntelligenceRunID,
            SessionStatus = session.Status,
            OverallBookProgress = overallProgressPercent,
            CurrentChapter = activeSnapshot.Run.ChapterNumber.HasValue ? $"Chapter {activeSnapshot.Run.ChapterNumber:0.##}" : "Chapter unknown",
            CurrentScene = CurrentSceneText(activeSnapshot),
            SnapshotSource = "Real",
            RunStatus = SessionStatus(session, snapshots),
            PersistedCompletedSceneCount = snapshots.Sum(snapshot => snapshot.Run.CompletedScenes ?? snapshot.Completed.Count),
            TotalPersistedSceneResultCount = totalPersistedResults,
            SuccessfullyParsedSceneResultCount = parsedScenes,
            FailedSceneResultCount = failed,
            HighestPersistedSceneResultId = snapshots.SelectMany(snapshot => snapshot.Results).Select(result => (int?)result.SceneResultID).Max(),
            HighestParsedSceneResultId = snapshots.SelectMany(snapshot => snapshot.Completed).Select(item => (int?)item.Result.SceneResultID).Max(),
            SelectedCurrentSceneResultId = current?.Result.SceneResultID,
            SelectedChapterAndSceneOrder = current is null ? "none" : $"Chapter {activeSnapshot.Run.ChapterNumber:0.##}, Scene {SceneSortNumber(current):0.##}",
            CurrentChangeToken = SessionChangeToken(session, snapshots),
            AnalysisCursor = FirstConfigured(activeSnapshot.Run.CurrentMessage, activeSnapshot.Run.CurrentStage, session.CurrentStage),
            Warning = warning
        };
    }

    private static StoryIntelligenceExperienceSnapshotDiagnostics BuildDiagnostics(
        StoryIntelligenceSavedRun run,
        IReadOnlyList<StoryIntelligenceSavedSceneResult> results,
        IReadOnlyList<ParsedSceneResult> parsed,
        IReadOnlyList<ParsedSceneResult> completed,
        ParsedSceneResult? current)
    {
        var failed = parsed.Where(item => item.Scene is null).ToList();
        var warning = failed.Count == 0
            ? null
            : $"{failed.Count:N0} scene result(s) skipped because they could not be parsed.";

        return new()
        {
            RequestedMode = "real",
            ActiveChapterRunId = run.StoryIntelligenceRunID,
            SessionStatus = run.Status,
            OverallBookProgress = Progress(run, run.CompletedScenes ?? completed.Count, Math.Max(run.TotalDetectedScenes ?? 0, results.Count)),
            CurrentChapter = run.ChapterNumber.HasValue ? $"Chapter {run.ChapterNumber:0.##}" : "Chapter unknown",
            CurrentScene = run.TotalDetectedScenes.HasValue
                ? $"Scene {Math.Clamp(run.CompletedScenes ?? completed.Count, 0, run.TotalDetectedScenes.Value):N0} of {run.TotalDetectedScenes.Value:N0}"
                : (current is null ? "Waiting" : $"Scene {SceneSortNumber(current):0.##}"),
            SnapshotSource = "Real",
            RunStatus = run.Status,
            PersistedCompletedSceneCount = run.CompletedScenes ?? 0,
            TotalPersistedSceneResultCount = results.Count,
            SuccessfullyParsedSceneResultCount = completed.Count,
            FailedSceneResultCount = failed.Count,
            HighestPersistedSceneResultId = results.Count == 0 ? null : results.Max(result => result.SceneResultID),
            HighestParsedSceneResultId = completed.Count == 0 ? null : completed.Max(item => item.Result.SceneResultID),
            SelectedCurrentSceneResultId = current?.Result.SceneResultID,
            SelectedChapterAndSceneOrder = current is null ? "none" : $"Chapter {SceneSortChapter(current):0.##}, Scene {SceneSortNumber(current):0.##}",
            CurrentChangeToken = ChangeToken(run, results),
            AnalysisCursor = FirstConfigured(run.CurrentMessage, run.CurrentStage),
            Warning = warning
        };
    }

    private static string SnapshotMessage(StoryIntelligenceSavedRun run, int completedScenes)
        => run.Status switch
        {
            StoryIntelligenceRunStatuses.Failed => FirstConfigured(run.ErrorMessage, "Story Intelligence run failed."),
            StoryIntelligenceRunStatuses.Cancelled => "Story Intelligence run was cancelled.",
            StoryIntelligenceRunStatuses.Completed or StoryIntelligenceRunStatuses.CompletedWithWarnings => "Analysis complete and ready for review.",
            _ when completedScenes == 0 => "Waiting for the first persisted scene analysis.",
            _ => FirstConfigured(run.CurrentMessage, "Analysis snapshot is updating.")
        };

    private static bool IsTerminal(string status)
        => status is StoryIntelligenceRunStatuses.Completed or StoryIntelligenceRunStatuses.CompletedWithWarnings or StoryIntelligenceRunStatuses.Failed or StoryIntelligenceRunStatuses.Cancelled;

    private static int SceneNumber(ParsedSceneResult item)
        => item.Scene?.SceneReference?.SceneNumber.HasValue == true ? Convert.ToInt32(item.Scene.SceneReference.SceneNumber.Value) : item.Result.TemporarySceneNumber;

    private static decimal SceneSortChapter(ParsedSceneResult item)
        => item.Scene?.SceneReference?.ChapterNumber
           ?? (item.Result.ChapterID.HasValue ? item.Result.ChapterID.Value : 0);

    private static decimal SceneSortNumber(ParsedSceneResult item)
        => item.Scene?.SceneReference?.SceneNumber ?? item.Result.TemporarySceneNumber;

    private static string SceneTitle(SceneIntelligenceScene scene, StoryIntelligenceSavedSceneResult result, int sceneNumber)
        => FirstConfigured(scene.SceneReference?.SourceLabel, result.SourceLabel, scene.Summary?.Short, $"Scene {sceneNumber:N0}");

    private static string TimelineLabel(SceneIntelligenceScene scene, StoryIntelligenceSavedSceneResult result)
        => FirstConfigured(scene.TimelineClues?.FirstOrDefault()?.AbsoluteDate, scene.Setting?.DateOrTimeReference, result.SourceLabel, "Known scene");

    private static int Progress(StoryIntelligenceSavedRun run, int completedScenes, int totalScenes)
    {
        if (IsTerminal(run.Status) && run.Status is not StoryIntelligenceRunStatuses.Failed)
        {
            return 100;
        }

        if (totalScenes > 0)
        {
            return Math.Clamp((int)Math.Round(completedScenes * 100m / totalScenes), 0, 99);
        }

        return run.Status == StoryIntelligenceRunStatuses.Running ? 8 : 0;
    }

    private static int OverallProgress(int completedScenes, int totalScenes, bool isTerminal)
    {
        if (isTerminal)
        {
            return 100;
        }

        if (totalScenes > 0)
        {
            return Math.Clamp((int)Math.Round(completedScenes * 100m / totalScenes), 0, 99);
        }

        return 0;
    }

    private static int BookProgress(IReadOnlyList<RunSnapshot> snapshots, int chapterTotal, bool isTerminal)
    {
        if (isTerminal)
        {
            return 100;
        }

        if (chapterTotal <= 0)
        {
            return 0;
        }

        var chapterProgress = snapshots.Sum(ChapterProgress);
        return Math.Clamp((int)Math.Floor(chapterProgress * 100m / chapterTotal), 0, 99);
    }

    private static decimal ChapterProgress(RunSnapshot snapshot)
    {
        if (IsTerminal(snapshot.Run.Status))
        {
            return 1m;
        }

        if (snapshot.Run.Status == StoryIntelligenceRunStatuses.Pending)
        {
            return 0m;
        }

        if ((snapshot.Run.TotalDetectedScenes ?? 0) > 0)
        {
            var sceneProgress = Math.Clamp((snapshot.Run.CompletedScenes ?? snapshot.Completed.Count) / Math.Max(1m, snapshot.Run.TotalDetectedScenes ?? 1), 0m, 1m);
            return Math.Clamp(0.25m + (sceneProgress * 0.7m), 0m, 0.95m);
        }

        return 0.15m;
    }

    private static string EstimateRemaining(StoryIntelligenceSavedRun run, int completedScenes, int totalScenes)
    {
        if (IsTerminal(run.Status))
        {
            return run.Status is StoryIntelligenceRunStatuses.Completed or StoryIntelligenceRunStatuses.CompletedWithWarnings ? "Ready to review" : run.Status;
        }

        if (completedScenes <= 0 || totalScenes <= completedScenes)
        {
            return "Calculating";
        }

        var elapsedMs = run.TotalDurationMs ?? Math.Max(0, Convert.ToInt64((DateTime.UtcNow - run.StartedUtc).TotalMilliseconds));
        var averageMs = elapsedMs / Math.Max(1, completedScenes);
        return FormatDuration(averageMs * (totalScenes - completedScenes));
    }

    private static string FormatDuration(long milliseconds)
    {
        var duration = TimeSpan.FromMilliseconds(Math.Max(0, milliseconds));
        return duration.TotalMinutes >= 1 ? $"{Math.Max(1, (int)Math.Round(duration.TotalMinutes)):N0} min" : $"{Math.Max(0, (int)Math.Round(duration.TotalSeconds)):N0} sec";
    }

    private static int ChapterCount(IEnumerable<ParsedSceneResult> completed)
        => Math.Max(1, completed.Select(item => item.Result.ChapterID ?? 0).Where(id => id > 0).Distinct().Count());

    private static string StageDisplay(StoryIntelligenceSavedRun run)
        => FirstConfigured(run.CurrentStage, run.Status);

    private static StoryIntelligenceExperienceLocationState PendingLocation()
        => new()
        {
            Id = "location-pending",
            LibraryCode = "loc-domestic-desk",
            Name = "Location not yet identified",
            Label = "Awaiting scene location",
            ImagePath = $"{FallbackRoot}/location-flat.svg"
        };

    private static string CharacterId(string? name) => $"character-result-{StableKey(name)}";

    private static int CharacterWeight(SceneIntelligenceCharacter character)
        => character.MentionedOnly == true ? 46 : ConfidenceWeight(character.Confidence, 72);

    private static int AssetWeight(SceneIntelligenceAsset asset)
        => ConfidenceWeight(asset.Confidence, string.IsNullOrWhiteSpace(asset.Status) ? 64 : 82);

    private static int ConfidenceWeight(decimal? confidence, int fallback)
        => Math.Clamp(confidence.HasValue ? (int)Math.Round(confidence.Value * 100m) : fallback, 30, 100);

    private static int Specificity(string? value)
        => string.IsNullOrWhiteSpace(value) ? 0 : value.Split(' ', StringSplitOptions.RemoveEmptyEntries).Length;

    private static bool IsLowValueAsset(SceneIntelligenceAsset asset)
    {
        var value = $"{asset.Name} {asset.AssetType} {asset.Notes}".ToLowerInvariant();
        return value.Contains("background", StringComparison.OrdinalIgnoreCase)
            || value.Contains("ordinary", StringComparison.OrdinalIgnoreCase)
            || value is "door" or "table" or "chair";
    }

    private static string CharacterLibraryCode(
        string name,
        SceneIntelligenceCharacter? character,
        SceneIntelligenceScene? scene = null,
        IReadOnlySet<string>? reservedCodes = null)
    {
        var profile = CharacterProfile.From(name, character, scene);
        var candidates = CharacterCodeProfiles
            .OrderByDescending(candidate => candidate.Score(profile))
            .ThenBy(candidate => reservedCodes?.Contains(candidate.Code) == true ? 1 : 0)
            .ThenBy(candidate => StableHash($"{name}|{candidate.Code}"))
            .ToList();

        return candidates.FirstOrDefault(candidate => reservedCodes?.Contains(candidate.Code) != true)?.Code
            ?? candidates.First().Code;
    }

    private static string LocationLibraryCode(string name, SceneIntelligenceLocation? location, SceneIntelligenceSetting? setting)
    {
        var value = $"{name} {location?.LocationType} {location?.GenericRoomType} {setting?.LocationType}".ToLowerInvariant();
        if (value.Contains("laundry") || value.Contains("utility")) return "loc-laundry-utility-room";
        if (value.Contains("stair")) return "loc-narrow-stairwell";
        if (value.Contains("car park") || value.Contains("parking")) return "loc-wet-car-park";
        if (value.Contains("flat") || value.Contains("apartment")) return "loc-small-flat-interior";
        if (value.Contains("house") || value.Contains("estate")) return "loc-estate-house-exterior";
        return "loc-domestic-desk";
    }

    private static string AssetLibraryCode(string name, SceneIntelligenceAsset asset)
    {
        var value = $"{name} {asset.AssetType} {asset.Status}".ToLowerInvariant();
        if (value.Contains("letter")) return "asset-folded-letter";
        if (value.Contains("notebook") || value.Contains("diary")) return "asset-worn-notebook";
        if (value.Contains("car") || value.Contains("vehicle")) return "asset-red-classic-car";
        if (value.Contains("key")) return "asset-old-keys";
        if (value.Contains("phone") || value.Contains("record")) return "asset-phone-recorder";
        if (value.Contains("photo")) return "asset-photo-print";
        if (value.Contains("map")) return "asset-map-pin";
        return "asset-locked-box";
    }

    private static string CharacterFallback(string name)
        => CharacterLibraryCode(name, null) switch
        {
            "char-young-adult-red-haired-witness" => $"{FallbackRoot}/character-rosie.svg",
            "char-middle-aged-weathered-man" => $"{FallbackRoot}/character-graham.svg",
            "char-older-soft-presence" => $"{FallbackRoot}/character-maggie.svg",
            "char-young-helper" => $"{FallbackRoot}/character-beth.svg",
            "char-archival-contact" => $"{FallbackRoot}/character-graham.svg",
            "char-professional-investigator" => $"{FallbackRoot}/character-graham.svg",
            "char-neighbourhood-friend" => $"{FallbackRoot}/character-beth.svg",
            "char-family-relative" => $"{FallbackRoot}/character-maggie.svg",
            "char-quiet-antagonist" => $"{FallbackRoot}/character-graham.svg",
            "char-authorial-voice" => $"{FallbackRoot}/character-maggie.svg",
            "char-unknown-figure" => $"{FallbackRoot}/character-beth.svg",
            _ => $"{FallbackRoot}/character-beth.svg"
        };

    private static string LocationFallback(string name)
        => LocationLibraryCode(name, null, null) switch
        {
            "loc-laundry-utility-room" => $"{FallbackRoot}/location-laundry.svg",
            "loc-narrow-stairwell" => $"{FallbackRoot}/location-stairwell.svg",
            "loc-wet-car-park" => $"{FallbackRoot}/location-car-park.svg",
            "loc-estate-house-exterior" => $"{FallbackRoot}/location-doweries.svg",
            _ => $"{FallbackRoot}/location-flat.svg"
        };

    private static string AssetFallback(string name)
        => AssetLibraryCode(name, new SceneIntelligenceAsset()) switch
        {
            "asset-folded-letter" => $"{FallbackRoot}/asset-letter.svg",
            "asset-worn-notebook" => $"{FallbackRoot}/asset-notebook.svg",
            "asset-red-classic-car" => $"{FallbackRoot}/asset-red-tr6.svg",
            "asset-old-keys" => $"{FallbackRoot}/asset-keys.svg",
            "asset-phone-recorder" => $"{FallbackRoot}/asset-phone.svg",
            _ => $"{FallbackRoot}/asset-letter.svg"
        };

    private static string StableKey(string? value)
    {
        var clean = Clean(value).ToLowerInvariant();
        if (string.IsNullOrWhiteSpace(clean))
        {
            return "unknown";
        }

        var builder = new StringBuilder();
        foreach (var ch in clean)
        {
            if (char.IsLetterOrDigit(ch))
            {
                builder.Append(ch);
            }
            else if (builder.Length > 0 && builder[^1] != '-')
            {
                builder.Append('-');
            }
        }

        return builder.ToString().Trim('-');
    }

    private static int StableHash(string? value)
    {
        var bytes = SHA256.HashData(Encoding.UTF8.GetBytes(value ?? string.Empty));
        return BitConverter.ToInt32(bytes, 0) & int.MaxValue;
    }

    private static string StableContentHash(string? value)
        => Convert.ToHexString(SHA256.HashData(Encoding.UTF8.GetBytes(value ?? string.Empty)))[..16].ToLowerInvariant();

    private static string Clean(string? value)
        => string.Join(' ', (value ?? string.Empty).Split(' ', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)).Trim();

    private static string FirstConfigured(params string?[] values)
        => values.FirstOrDefault(value => !string.IsNullOrWhiteSpace(value))?.Trim() ?? string.Empty;

    private static string DisplayTitle(string? value, string fallback)
        => string.IsNullOrWhiteSpace(value) ? fallback : value.Trim();

    private static string Trim(string? value, int max)
    {
        var clean = Clean(value);
        return clean.Length <= max ? clean : clean[..Math.Max(0, max - 3)].TrimEnd() + "...";
    }

    private sealed record RunSnapshot(
        StoryIntelligenceSavedRun Run,
        IReadOnlyList<StoryIntelligenceSavedSceneResult> Results,
        IReadOnlyList<ParsedSceneResult> Parsed,
        IReadOnlyList<ParsedSceneResult> Completed,
        ParsedSceneResult? Current);

    private sealed record ParsedSceneResult(StoryIntelligenceSavedSceneResult Result, SceneIntelligenceScene? Scene, string? ParseError);

    private sealed record CharacterCodeProfile(
        string Code,
        string AgeBand,
        string Presentation,
        string HairColour,
        string HairLength,
        IReadOnlyList<string> Signals)
    {
        public int Score(CharacterProfile profile)
        {
            var score = 0;
            if (profile.AgeBand == AgeBand) score += 80;
            else if (CompatibleAge(profile.AgeBand, AgeBand)) score += 30;
            else score -= 45;

            if (!string.IsNullOrWhiteSpace(profile.Presentation) && Presentation.Equals(profile.Presentation, StringComparison.OrdinalIgnoreCase)) score += 24;
            if (!string.IsNullOrWhiteSpace(profile.HairColour) && HairColour.Equals(profile.HairColour, StringComparison.OrdinalIgnoreCase)) score += 18;
            if (!string.IsNullOrWhiteSpace(profile.HairLength) && HairLength.Equals(profile.HairLength, StringComparison.OrdinalIgnoreCase)) score += 10;
            score += Signals.Count(signal => profile.Text.Contains(signal, StringComparison.OrdinalIgnoreCase)) * 14;
            return score;
        }

        private static bool CompatibleAge(string required, string candidate)
            => (required, candidate) switch
            {
                ("Teen", "YoungAdult") => true,
                ("YoungAdult", "Teen") => true,
                ("MiddleAged", "Older") => true,
                ("Older", "MiddleAged") => true,
                _ => false
            };
    }

    private sealed record CharacterProfile(string Text, string AgeBand, string Presentation, string HairColour, string HairLength)
    {
        public static CharacterProfile From(string name, SceneIntelligenceCharacter? character, SceneIntelligenceScene? scene)
        {
            var relationshipText = string.Join(' ', (scene?.Relationships ?? [])
                .Where(relationship => string.Equals(Clean(relationship.CharacterA), Clean(name), StringComparison.OrdinalIgnoreCase)
                    || string.Equals(Clean(relationship.CharacterB), Clean(name), StringComparison.OrdinalIgnoreCase))
                .Select(relationship => $"{relationship.RelationshipSignal} {relationship.Evidence}"));
            var text = $"{name} {character?.RoleInScene} {character?.Notes} {string.Join(' ', character?.Actions ?? [])} {relationshipText}".ToLowerInvariant();
            return new(
                text,
                DetectAgeBand(text),
                DetectPresentation(text),
                DetectHairColour(text),
                DetectHairLength(text));
        }

        private static string DetectAgeBand(string text)
        {
            if (text.Contains("grandmother") || text.Contains("grandfather") || text.Contains("elderly") || text.Contains("older") || text.Contains("retired")) return "Older";
            if (text.Contains("mother") || text.Contains("father") || text.Contains("parent") || text.Contains("teacher") || text.Contains("aunt") || text.Contains("uncle") || text.Contains("middle-aged") || text.Contains("middle aged")) return "MiddleAged";
            if (text.Contains("teen") || text.Contains("teenage") || text.Contains("15") || text.Contains("fifteen") || text.Contains("schoolgirl") || text.Contains("schoolboy") || text.Contains("child") || text.Contains("daughter") || text.Contains("son")) return "Teen";
            if (text.Contains("young") || text.Contains("student")) return "YoungAdult";
            return "YoungAdult";
        }

        private static string DetectPresentation(string text)
        {
            if (text.Contains("mother") || text.Contains("daughter") || text.Contains("woman") || text.Contains("girl") || text.Contains("female") || text.Contains("sister") || text.Contains("aunt")) return "Feminine";
            if (text.Contains("father") || text.Contains("son") || text.Contains("man") || text.Contains("male") || text.Contains("brother") || text.Contains("uncle")) return "Masculine";
            return string.Empty;
        }

        private static string DetectHairColour(string text)
        {
            if (text.Contains("red") || text.Contains("auburn") || text.Contains("ginger")) return "Red";
            if (text.Contains("grey") || text.Contains("gray") || text.Contains("white-haired") || text.Contains("white hair")) return "Grey";
            if (text.Contains("black hair") || text.Contains("black-haired")) return "Black";
            if (text.Contains("dark") || text.Contains("brown") || text.Contains("brunette")) return "Brown";
            return string.Empty;
        }

        private static string DetectHairLength(string text)
        {
            if (text.Contains("long hair") || text.Contains("long-haired")) return "Long";
            if (text.Contains("short hair") || text.Contains("short-haired")) return "Short";
            return string.Empty;
        }
    }

    private static readonly IReadOnlyList<CharacterCodeProfile> CharacterCodeProfiles =
    [
        new("char-young-helper", "Teen", "Androgynous", "Black", "Short", ["teen", "child", "daughter", "son", "helper"]),
        new("char-young-adult-red-haired-witness", "YoungAdult", "Feminine", "Red", "Long", ["red", "auburn", "witness", "protective"]),
        new("char-young-adult-brunette-observer", "YoungAdult", "Feminine", "Brown", "Medium", ["young", "observer", "student"]),
        new("char-neighbourhood-friend", "YoungAdult", "Androgynous", "Brown", "Medium", ["friend", "neighbour", "neighbor"]),
        new("char-family-relative", "MiddleAged", "Feminine", "Brown", "Medium", ["mother", "parent", "aunt", "family", "relative"]),
        new("char-professional-investigator", "MiddleAged", "Androgynous", "Brown", "Short", ["teacher", "professional", "investigator", "authority"]),
        new("char-middle-aged-weathered-man", "MiddleAged", "Masculine", "DarkBrown", "Short", ["father", "man", "suspect", "threat", "weathered"]),
        new("char-quiet-antagonist", "MiddleAged", "Androgynous", "DarkBrown", "Short", ["antagonist", "threat", "pressure", "controlled"]),
        new("char-older-soft-presence", "Older", "Feminine", "Grey", "Short", ["grandmother", "older", "remembered", "mother"]),
        new("char-archival-contact", "Older", "Masculine", "White", "Short", ["grandfather", "older", "archive", "records"]),
        new("char-authorial-voice", "Older", "Androgynous", "Grey", "Medium", ["voice", "memory", "recorded"]),
        new("char-unknown-figure", "YoungAdult", "Androgynous", "Brown", "Medium", ["unknown", "unidentified"])
    ];
}