using Dapper;
using PlotLine.Data;

namespace PlotLine.Services;

public interface IStoryIntelligenceDevelopmentResetService
{
    Task<StoryIntelligenceDevelopmentResetResult> ResetOwnedProjectsAndImportsAsync(int userId, CancellationToken cancellationToken = default);
}

public sealed class StoryIntelligenceDevelopmentResetService(
    ISqlConnectionFactory connectionFactory,
    ILogger<StoryIntelligenceDevelopmentResetService> logger) : IStoryIntelligenceDevelopmentResetService
{
    public async Task<StoryIntelligenceDevelopmentResetResult> ResetOwnedProjectsAndImportsAsync(int userId, CancellationToken cancellationToken = default)
    {
        using var connection = connectionFactory.CreateConnection();
        var command = new CommandDefinition(PrepareResetSql, new { UserID = userId }, cancellationToken: cancellationToken, commandTimeout: 120);
        var summary = await connection.QuerySingleAsync<PreparedResetSummary>(command);

        foreach (var projectId in summary.ProjectIdList)
        {
            var deleteCommand = new CommandDefinition(
                "dbo.ProjectHardDelete_ForOwner",
                new { ProjectID = projectId, UserID = userId },
                commandType: System.Data.CommandType.StoredProcedure,
                cancellationToken: cancellationToken,
                commandTimeout: 120);
            await connection.ExecuteAsync(deleteCommand);
        }

        var verificationCommand = new CommandDefinition(VerifyResetSql, new { UserID = userId }, cancellationToken: cancellationToken, commandTimeout: 120);
        var verification = await connection.QuerySingleAsync<ResetVerification>(verificationCommand);
        var result = new StoryIntelligenceDevelopmentResetResult(
            summary.ProjectIdList.Count,
            summary.ImportSessionCount,
            summary.RunCount,
            verification.RemainingProjects,
            verification.RemainingImports,
            verification.RemainingRuns,
            verification.PreservedIllustrationItems);

        logger.LogWarning(
            "Admin Story Intelligence reset completed for user {UserId}. DeletedProjects={DeletedProjects} DeletedImports={DeletedImports} DeletedRuns={DeletedRuns} PreservedIllustrationItems={PreservedIllustrationItems}.",
            userId,
            result.DeletedProjects,
            result.DeletedImportSessions,
            result.DeletedRuns,
            result.PreservedIllustrationItems);

        return result;
    }

    private const string PrepareResetSql = """
SET NOCOUNT ON;

DECLARE @ProjectIDs TABLE (ProjectID int NOT NULL PRIMARY KEY);
DECLARE @BookIDs TABLE (BookID int NOT NULL PRIMARY KEY);
DECLARE @ImportSessionIDs TABLE (ImportSessionID int NOT NULL PRIMARY KEY);
DECLARE @RunIDs TABLE (StoryIntelligenceRunID int NOT NULL PRIMARY KEY);

INSERT @ProjectIDs (ProjectID)
SELECT DISTINCT p.ProjectID
FROM dbo.Projects p
INNER JOIN dbo.ProjectUserAccess pua ON pua.ProjectID = p.ProjectID
WHERE pua.UserID = @UserID
    AND pua.AccessRole = N'Owner'
    AND pua.IsActive = 1;

INSERT @BookIDs (BookID)
SELECT b.BookID
FROM dbo.Books b
INNER JOIN @ProjectIDs p ON p.ProjectID = b.ProjectID;

INSERT @ImportSessionIDs (ImportSessionID)
SELECT StoryIntelligenceBookPipelineID
FROM dbo.StoryIntelligenceBookPipelines pipeline
WHERE EXISTS (SELECT 1 FROM @ProjectIDs p WHERE p.ProjectID = pipeline.ProjectID)
    OR EXISTS (SELECT 1 FROM @BookIDs b WHERE b.BookID = pipeline.BookID);

INSERT @RunIDs (StoryIntelligenceRunID)
SELECT StoryIntelligenceRunID
FROM dbo.StoryIntelligenceRuns run
WHERE run.UserID = @UserID
    AND (
        run.ProjectID IS NULL
        OR EXISTS (SELECT 1 FROM @ProjectIDs p WHERE p.ProjectID = run.ProjectID)
        OR EXISTS (SELECT 1 FROM @BookIDs b WHERE b.BookID = run.BookID)
    );

DECLARE @ImportSessionCount int = (SELECT COUNT(*) FROM @ImportSessionIDs);
DECLARE @RunCount int = (SELECT COUNT(*) FROM @RunIDs);

UPDATE dbo.StoryIntelligenceRuns
SET Status = CASE WHEN Status IN (N'Pending', N'Running') THEN N'Cancelled' ELSE Status END,
    CurrentStage = N'Cancelled before admin reset',
    CurrentMessage = N'Admin reset invalidated this run while preserving generated illustrations.',
    CancellationRequestedUtc = COALESCE(CancellationRequestedUtc, SYSUTCDATETIME()),
    CancelledUtc = COALESCE(CancelledUtc, SYSUTCDATETIME()),
    CompletedUtc = COALESCE(CompletedUtc, SYSUTCDATETIME()),
    UpdatedUtc = SYSUTCDATETIME()
WHERE EXISTS (SELECT 1 FROM @RunIDs ids WHERE ids.StoryIntelligenceRunID = StoryIntelligenceRuns.StoryIntelligenceRunID)
    AND Status IN (N'Pending', N'Running');

DELETE FROM dbo.StoryMemoryIllustrationAssignments
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryMemoryIllustrationAssignments.ImportSessionID);

DELETE FROM dbo.StoryMemoryIllustrationDemands
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryMemoryIllustrationDemands.ImportSessionID);

DELETE FROM dbo.StoryMemoryRelationships
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryMemoryRelationships.ImportSessionID);

DELETE FROM dbo.StoryMemoryCharacterAttributes
WHERE EXISTS
(
    SELECT 1
    FROM dbo.StoryMemoryCharacters c
    INNER JOIN @ImportSessionIDs ids ON ids.ImportSessionID = c.ImportSessionID
    WHERE c.StoryMemoryCharacterID = StoryMemoryCharacterAttributes.StoryMemoryCharacterID
);

DELETE FROM dbo.StoryMemoryCharacterAliases
WHERE EXISTS
(
    SELECT 1
    FROM dbo.StoryMemoryCharacters c
    INNER JOIN @ImportSessionIDs ids ON ids.ImportSessionID = c.ImportSessionID
    WHERE c.StoryMemoryCharacterID = StoryMemoryCharacterAliases.StoryMemoryCharacterID
);

DELETE FROM dbo.StoryMemoryAssets
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryMemoryAssets.ImportSessionID);

DELETE FROM dbo.StoryMemoryLocations
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryMemoryLocations.ImportSessionID);

DELETE FROM dbo.StoryMemoryCharacters
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryMemoryCharacters.ImportSessionID);

DELETE FROM dbo.StoryMemoryProcessedSceneResults
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryMemoryProcessedSceneResults.ImportSessionID);

DELETE FROM dbo.StoryMemoryImportPreferences
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryMemoryImportPreferences.ImportSessionID);

DELETE FROM dbo.StoryIntelligenceCharacterIllustrationAssignments
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryIntelligenceCharacterIllustrationAssignments.ImportSessionID)
    OR EXISTS (SELECT 1 FROM @ProjectIDs p WHERE p.ProjectID = StoryIntelligenceCharacterIllustrationAssignments.ProjectID);

DELETE FROM dbo.StoryIntelligenceIllustrationDemands
WHERE EXISTS (SELECT 1 FROM @ProjectIDs p WHERE p.ProjectID = StoryIntelligenceIllustrationDemands.ProjectID);

DELETE FROM dbo.StoryIntelligenceBookPipelines
WHERE EXISTS (SELECT 1 FROM @ImportSessionIDs ids WHERE ids.ImportSessionID = StoryIntelligenceBookPipelines.StoryIntelligenceBookPipelineID);

DELETE FROM dbo.StoryIntelligenceSceneResults
WHERE EXISTS (SELECT 1 FROM @RunIDs ids WHERE ids.StoryIntelligenceRunID = StoryIntelligenceSceneResults.StoryIntelligenceRunID);

DELETE FROM dbo.StoryIntelligenceChapterResults
WHERE EXISTS (SELECT 1 FROM @RunIDs ids WHERE ids.StoryIntelligenceRunID = StoryIntelligenceChapterResults.StoryIntelligenceRunID);

DELETE FROM dbo.StoryIntelligenceImportCommits
WHERE EXISTS (SELECT 1 FROM @RunIDs ids WHERE ids.StoryIntelligenceRunID = StoryIntelligenceImportCommits.StoryIntelligenceRunID);

DELETE FROM dbo.StoryIntelligenceRuns
WHERE EXISTS (SELECT 1 FROM @RunIDs ids WHERE ids.StoryIntelligenceRunID = StoryIntelligenceRuns.StoryIntelligenceRunID);

UPDATE dbo.Projects
SET IsArchived = 1,
    ArchivedDate = COALESCE(ArchivedDate, SYSUTCDATETIME()),
    ArchivedReason = N'Admin Story Intelligence reset preserving generated illustrations',
    UpdatedDate = SYSUTCDATETIME()
WHERE EXISTS (SELECT 1 FROM @ProjectIDs ids WHERE ids.ProjectID = Projects.ProjectID);

SELECT
    ProjectIds = COALESCE(STRING_AGG(CONVERT(varchar(20), ProjectID), ','), ''),
    ImportSessionCount = @ImportSessionCount,
    RunCount = @RunCount
FROM @ProjectIDs;
""";

    private const string VerifyResetSql = """
SELECT
    RemainingProjects = (
        SELECT COUNT(*)
        FROM dbo.Projects p
        INNER JOIN dbo.ProjectUserAccess pua ON pua.ProjectID = p.ProjectID
        WHERE pua.UserID = @UserID AND pua.AccessRole = N'Owner' AND pua.IsActive = 1
    ),
    RemainingImports = (
        SELECT COUNT(*)
        FROM dbo.StoryIntelligenceBookPipelines pipeline
        INNER JOIN dbo.ProjectUserAccess pua ON pua.ProjectID = pipeline.ProjectID
        WHERE pua.UserID = @UserID AND pua.AccessRole = N'Owner' AND pua.IsActive = 1
    ),
    RemainingRuns = (
        SELECT COUNT(*)
        FROM dbo.StoryIntelligenceRuns
        WHERE UserID = @UserID
    ),
    PreservedIllustrationItems = (
        SELECT COUNT(*)
        FROM dbo.IllustrationLibraryItems
        WHERE Category IN (N'Character', N'Location', N'Asset')
    );
""";

    private sealed class PreparedResetSummary
    {
        public string ProjectIds { get; init; } = string.Empty;
        public int ImportSessionCount { get; init; }
        public int RunCount { get; init; }

        public IReadOnlyList<int> ProjectIdList => SplitProjectIds(ProjectIds);
    }

    private sealed class ResetVerification
    {
        public int RemainingProjects { get; init; }
        public int RemainingImports { get; init; }
        public int RemainingRuns { get; init; }
        public int PreservedIllustrationItems { get; init; }
    }

    private static IReadOnlyList<int> SplitProjectIds(string projectIds)
        => string.IsNullOrWhiteSpace(projectIds)
            ? []
            : projectIds.Split(',', StringSplitOptions.RemoveEmptyEntries | StringSplitOptions.TrimEntries)
                .Select(value => int.TryParse(value, out var id) ? id : 0)
                .Where(id => id > 0)
                .ToArray();
}

public sealed record StoryIntelligenceDevelopmentResetResult(
    int DeletedProjects,
    int DeletedImportSessions,
    int DeletedRuns,
    int RemainingProjects,
    int RemainingImportSessions,
    int RemainingRuns,
    int PreservedIllustrationItems)
{
    public bool Success => RemainingProjects == 0 && RemainingImportSessions == 0 && RemainingRuns == 0;

    public string Message => Success
        ? $"Reset complete. Deleted {DeletedProjects:N0} project(s), {DeletedImportSessions:N0} import(s) and {DeletedRuns:N0} run(s). Preserved {PreservedIllustrationItems:N0} generated image record(s)."
        : $"Reset finished with remaining data: {RemainingProjects:N0} project(s), {RemainingImportSessions:N0} import(s), {RemainingRuns:N0} run(s). Preserved {PreservedIllustrationItems:N0} generated image record(s).";
}