using GB5Shared.DTO.Framework.Login;
using GB5Shared.Resource.Response;
using Microsoft.Extensions.Logging;
using TCMSBLL.Interfaces;
using TCMSDAL.DTO;
using TCMSDAL.Interfaces;

namespace TCMSBLL.Implementations;

public class TCMSTraceabilityBLL : ITCMSTraceabilityBLL
{
    private readonly ITCMSTraceabilityDAL       _Dal;
    private readonly ILogger<TCMSTraceabilityBLL> _Log;

    public TCMSTraceabilityBLL(
        ITCMSTraceabilityDAL dal,
        ILogger<TCMSTraceabilityBLL> logger)
    {
        _Dal = dal;
        _Log = logger;
    }

    // ── Screen links ──────────────────────────────────────────────────────────

    public async Task<string> LinkScreenAsync(
        TCMSSaveLinkDTO dto, LoginDTO login, CancellationToken ct)
    {
        if (dto.TestCaseId <= 0)         return "Test case is required.";
        if (string.IsNullOrWhiteSpace(dto.ScreenRoute))  return "Screen route is required.";
        if (string.IsNullOrWhiteSpace(dto.ScreenTitle))  return "Screen title is required.";
        if (string.IsNullOrWhiteSpace(dto.ModuleName))   return "Module name is required.";

        var id = await _Dal.InsertScreenLinkAsync(dto, login, ct).ConfigureAwait(false);
        return $"{SuccessResponse.SaveSuccessMessage} {id}";
    }

    public async Task<string> UnlinkScreenAsync(
        int screenLinkId, LoginDTO login, CancellationToken ct)
    {
        await _Dal.DeleteScreenLinkAsync(screenLinkId, login, ct).ConfigureAwait(false);
        return SuccessResponse.DeleteSuccessMessage;
    }

    public Task<IEnumerable<TCMSScreenLinkDTO>> GetScreenLinksForTestCaseAsync(
        int testCaseId, LoginDTO login, CancellationToken ct)
        => _Dal.GetScreenLinksForTestCaseAsync(testCaseId, login, ct);

    // ── API links ─────────────────────────────────────────────────────────────

    public async Task<string> LinkApiAsync(
        TCMSSaveApiLinkDTO dto, LoginDTO login, CancellationToken ct)
    {
        if (dto.TestCaseId <= 0)      return "Test case is required.";
        if (string.IsNullOrWhiteSpace(dto.ApiPath))   return "API path is required.";
        if (string.IsNullOrWhiteSpace(dto.HttpMethod)) return "HTTP method is required.";

        var id = await _Dal.InsertApiLinkAsync(dto, login, ct).ConfigureAwait(false);
        return $"{SuccessResponse.SaveSuccessMessage} {id}";
    }

    public async Task<string> UnlinkApiAsync(
        int apiLinkId, LoginDTO login, CancellationToken ct)
    {
        await _Dal.DeleteApiLinkAsync(apiLinkId, login, ct).ConfigureAwait(false);
        return SuccessResponse.DeleteSuccessMessage;
    }

    public Task<IEnumerable<TCMSApiLinkDTO>> GetApiLinksForTestCaseAsync(
        int testCaseId, LoginDTO login, CancellationToken ct)
        => _Dal.GetApiLinksForTestCaseAsync(testCaseId, login, ct);

    // ── GetByScreen — merges summary + test cases + steps ────────────────────

    public async Task<TCMSScreenCoverageDTO> GetByScreenAsync(
        string screenRoute, LoginDTO login, CancellationToken ct)
    {
        // Summary (aggregates from link table only — tag-based cases counted by query)
        var summary = await _Dal.GetScreenSummaryAsync(screenRoute, login, ct)
            .ConfigureAwait(false)
            ?? new TCMSScreenCoverageDTO
            {
                ScreenRoute = screenRoute,
                ScreenTitle = screenRoute,
                ModuleName  = string.Empty,
            };

        // Test case rows (link table UNION tags — see QB dual-source query)
        var cases = (await _Dal.GetTestCasesByScreenAsync(screenRoute, login, ct)
            .ConfigureAwait(false)).ToList();

        if (cases.Count > 0)
            await HydrateStepsAsync(cases, login, ct).ConfigureAwait(false);

        summary.TestCases  = cases;
        summary.TotalCases = cases.Count;
        return summary;
    }

    // ── GetByApiOperation ─────────────────────────────────────────────────────

    public async Task<TCMSApiCoverageDTO> GetByApiOperationAsync(
        long apiOperationId, LoginDTO login, CancellationToken ct)
    {
        var cases = (await _Dal.GetTestCasesByApiOperationAsync(apiOperationId, login, ct)
            .ConfigureAwait(false)).ToList();

        if (cases.Count > 0)
            await HydrateStepsAsync(cases, login, ct).ConfigureAwait(false);

        return new TCMSApiCoverageDTO
        {
            TotalCases  = cases.Count,
            PassCount   = cases.Count(c => c.LastRunStatus == "Pass"),
            FailCount   = cases.Count(c => c.LastRunStatus == "Fail"),
            LastRunDate = cases.Max(c => c.LastRunDate),
            TestCases   = cases,
        };
    }

    // ── Shared helper — bulk-load steps and attach to case list ──────────────

    private async Task HydrateStepsAsync(
        List<TCMSTracedTestCaseDTO> cases, LoginDTO login, CancellationToken ct)
    {
        var steps = await _Dal.GetStepsForCasesAsync(
            cases.Select(c => c.TestCaseId), login, ct).ConfigureAwait(false);

        var stepsByCase = steps.GroupBy(s => s.TestCaseId)
            .ToDictionary(g => g.Key, g => (IEnumerable<TCMSTracedStepDTO>)g.ToList());

        foreach (var tc in cases)
            tc.Steps = stepsByCase.TryGetValue(tc.TestCaseId, out var s)
                ? s
                : Enumerable.Empty<TCMSTracedStepDTO>();
    }

    // ── Screen tree ───────────────────────────────────────────────────────────

    public Task<IEnumerable<TCMSScreenTreeNodeDTO>> GetScreenTreeAsync(
        LoginDTO login, CancellationToken ct)
        => _Dal.GetScreenTreeAsync(login, ct);

    // ── Gap detection ─────────────────────────────────────────────────────────

    public async Task<IEnumerable<TCMSCoverageGapDTO>> GetCoverageGapsAsync(
        LoginDTO login, CancellationToken ct)
    {
        var screenGaps = await _Dal.GetScreenGapsAsync(login, ct).ConfigureAwait(false);
        var apiGaps    = await _Dal.GetApiGapsAsync(login, ct).ConfigureAwait(false);
        return screenGaps.Concat(apiGaps);
    }
}