using System.Data;
using System.Text.Json;
using Dapper;
using PlotLine.Models;

namespace PlotLine.Data;

public interface ICharacterEnrichmentRepository
{
    Task<CharacterEnrichmentRun> QueueAsync(CharacterEnrichmentQueueRequest request);
    Task<CharacterEnrichmentRun> QueueCharacterAsync(CharacterEnrichmentCharacterQueueRequest request);
    Task<CharacterEnrichmentRun?> RetryAsync(int bookId, int userId);
    Task<CharacterEnrichmentRun?> ClaimNextAsync(int leaseMinutes);
    Task<CharacterEnrichmentRun?> GetCurrentAsync(int bookId);
    Task<CharacterEnrichmentRun?> GetCurrentForCharacterAsync(int characterId, int userId);
    Task<CharacterEnrichmentCharacterStatus?> GetCharacterStatusAsync(int characterId, int userId);
    Task UpdateProgressAsync(CharacterEnrichmentProgressUpdate update);
    Task CompleteAsync(CharacterEnrichmentCompletionRequest request, IReadOnlyList<CharacterEnrichmentCharacterResult> results);
    Task FailAsync(int runId, string errorMessage, string? errorDetail, long? durationMs);
    Task<CharacterEnrichmentContext> BuildContextAsync(int projectId, int bookId);
    Task<CharacterEnrichmentContext> BuildContextAsync(int projectId, int bookId, int? characterId);
}

public sealed class CharacterEnrichmentRepository(ISqlConnectionFactory connectionFactory) : ICharacterEnrichmentRepository
{
    private static readonly JsonSerializerOptions JsonOptions = new(JsonSerializerDefaults.Web);

    public async Task<CharacterEnrichmentRun> QueueAsync(CharacterEnrichmentQueueRequest request)
    {
        using var connection = connectionFactory.CreateConnection();
        return await connection.QuerySingleAsync<CharacterEnrichmentRun>(
            "dbo.CharacterEnrichmentRun_Queue",
            request,
            commandType: CommandType.StoredProcedure);
    }

    public async Task<CharacterEnrichmentRun> QueueCharacterAsync(CharacterEnrichmentCharacterQueueRequest request)
    {
        using var connection = connectionFactory.CreateConnection();
        return await connection.QuerySingleAsync<CharacterEnrichmentRun>(
            "dbo.CharacterEnrichmentRun_QueueCharacter",
            request,
            commandType: CommandType.StoredProcedure);
    }

    public async Task<CharacterEnrichmentRun?> RetryAsync(int bookId, int userId)
    {
        using var connection = connectionFactory.CreateConnection();
        return await connection.QuerySingleOrDefaultAsync<CharacterEnrichmentRun>(
            "dbo.CharacterEnrichmentRun_Retry",
            new { BookID = bookId, UserID = userId },
            commandType: CommandType.StoredProcedure);
    }

    public async Task<CharacterEnrichmentRun?> ClaimNextAsync(int leaseMinutes)
    {
        using var connection = connectionFactory.CreateConnection();
        return await connection.QuerySingleOrDefaultAsync<CharacterEnrichmentRun>(
            "dbo.CharacterEnrichmentRun_ClaimNext",
            new { LeaseMinutes = leaseMinutes },
            commandType: CommandType.StoredProcedure);
    }

    public async Task<CharacterEnrichmentRun?> GetCurrentAsync(int bookId)
    {
        using var connection = connectionFactory.CreateConnection();
        return await connection.QuerySingleOrDefaultAsync<CharacterEnrichmentRun>(
            "dbo.CharacterEnrichmentRun_GetCurrentByBook",
            new { BookID = bookId },
            commandType: CommandType.StoredProcedure);
    }

    public async Task<CharacterEnrichmentRun?> GetCurrentForCharacterAsync(int characterId, int userId)
    {
        using var connection = connectionFactory.CreateConnection();
        return await connection.QuerySingleOrDefaultAsync<CharacterEnrichmentRun>(
            "dbo.CharacterEnrichmentRun_GetCurrentByCharacter",
            new { CharacterID = characterId, UserID = userId },
            commandType: CommandType.StoredProcedure);
    }

    public async Task<CharacterEnrichmentCharacterStatus?> GetCharacterStatusAsync(int characterId, int userId)
    {
        using var connection = connectionFactory.CreateConnection();
        return await connection.QuerySingleOrDefaultAsync<CharacterEnrichmentCharacterStatus>(
            "dbo.CharacterEnrichmentCharacterStatus_Get",
            new { CharacterID = characterId, UserID = userId },
            commandType: CommandType.StoredProcedure);
    }

    public async Task UpdateProgressAsync(CharacterEnrichmentProgressUpdate update)
    {
        using var connection = connectionFactory.CreateConnection();
        await connection.ExecuteAsync(
            "dbo.CharacterEnrichmentRun_UpdateProgress",
            update,
            commandType: CommandType.StoredProcedure);
    }

    public async Task CompleteAsync(CharacterEnrichmentCompletionRequest request, IReadOnlyList<CharacterEnrichmentCharacterResult> results)
    {
        using var connection = connectionFactory.CreateConnection();
        await connection.ExecuteAsync(
            "dbo.CharacterEnrichmentRun_Complete",
            new
            {
                request.CharacterEnrichmentRunID,
                request.Model,
                request.InputTokens,
                request.OutputTokens,
                request.TotalTokens,
                request.DurationMs,
                ResultsJson = JsonSerializer.Serialize(results, JsonOptions)
            },
            commandType: CommandType.StoredProcedure);
    }

    public async Task FailAsync(int runId, string errorMessage, string? errorDetail, long? durationMs)
    {
        using var connection = connectionFactory.CreateConnection();
        await connection.ExecuteAsync(
            "dbo.CharacterEnrichmentRun_Fail",
            new
            {
                CharacterEnrichmentRunID = runId,
                ErrorMessage = errorMessage,
                ErrorDetail = errorDetail,
                DurationMs = durationMs
            },
            commandType: CommandType.StoredProcedure);
    }

    public async Task<CharacterEnrichmentContext> BuildContextAsync(int projectId, int bookId)
        => await BuildContextAsync(projectId, bookId, null);

    public async Task<CharacterEnrichmentContext> BuildContextAsync(int projectId, int bookId, int? characterId)
    {
        using var connection = connectionFactory.CreateConnection();
        using var result = await connection.QueryMultipleAsync(
            "dbo.CharacterEnrichment_ContextGet",
            new { ProjectID = projectId, BookID = bookId, CharacterID = characterId },
            commandType: CommandType.StoredProcedure);

        var book = await result.ReadSingleAsync<ContextBookRow>();
        var characters = (await result.ReadAsync<CharacterEnrichmentCharacterContext>()).ToList();
        var aliases = (await result.ReadAsync<ContextAliasRow>()).ToList();
        var scenes = (await result.ReadAsync<ContextSceneRow>()).ToList();

        var aliasesByCharacter = aliases
            .GroupBy(alias => alias.CharacterID)
            .ToDictionary(group => group.Key, group => (IReadOnlyList<string>)group.Select(alias => alias.Alias).ToList());
        var scenesByCharacter = scenes
            .GroupBy(scene => scene.CharacterID)
            .ToDictionary(
                group => group.Key,
                group => (IReadOnlyList<CharacterEnrichmentSceneContext>)group.Select(scene => new CharacterEnrichmentSceneContext
                {
                    SceneID = scene.SceneID,
                    ChapterID = scene.ChapterID,
                    ChapterNumber = scene.ChapterNumber,
                    ChapterTitle = scene.ChapterTitle,
                    SceneNumber = scene.SceneNumber,
                    SceneTitle = scene.SceneTitle,
                    SourceText = scene.SourceText
                }).ToList());

        return new CharacterEnrichmentContext
        {
            ProjectID = projectId,
            BookID = bookId,
            BookTitle = book.BookTitle,
            StoryEra = book.StoryEra,
            SeriesStartDate = book.SeriesStartDate,
            Characters = characters.Select(character => new CharacterEnrichmentCharacterContext
            {
                CharacterID = character.CharacterID,
                CharacterName = character.CharacterName,
                BirthDate = character.BirthDate,
                AgeAtSeriesStart = character.AgeAtSeriesStart,
                Height = character.Height,
                EyeColour = character.EyeColour,
                DefaultDescription = character.DefaultDescription,
                Aliases = aliasesByCharacter.GetValueOrDefault(character.CharacterID) ?? [],
                Scenes = scenesByCharacter.GetValueOrDefault(character.CharacterID) ?? []
            }).ToList()
        };
    }

    private sealed class ContextBookRow
    {
        public string BookTitle { get; init; } = string.Empty;
        public string? StoryEra { get; init; }
        public DateTime? SeriesStartDate { get; init; }
    }

    private sealed class ContextAliasRow
    {
        public int CharacterID { get; init; }
        public string Alias { get; init; } = string.Empty;
    }

    private sealed class ContextSceneRow
    {
        public int CharacterID { get; init; }
        public int SceneID { get; init; }
        public int ChapterID { get; init; }
        public decimal ChapterNumber { get; init; }
        public string ChapterTitle { get; init; } = string.Empty;
        public decimal SceneNumber { get; init; }
        public string SceneTitle { get; init; } = string.Empty;
        public string SourceText { get; init; } = string.Empty;
    }
}