using System.Collections.Concurrent;
using AVSCartonShipmentVerifier.DTOs;

namespace AVSCartonShipmentVerifier.Services;

public sealed class InMemoryScanHistoryStore : IScanHistoryStore
{
    private const int MaxItems = 5;
    private readonly ConcurrentQueue<ScannedRecordDto> _successful = new();
    private readonly ConcurrentQueue<RejectedScanRecordDto> _rejected = new();
    private readonly Lock _syncLock = new();

    public Task AddSuccessfulScanAsync(ScannedRecordDto record, CancellationToken cancellationToken = default)
    {
        lock (_syncLock)
        {
            _successful.Enqueue(record);
            while (_successful.Count > MaxItems)
            {
                _successful.TryDequeue(out _);
            }
        }

        return Task.CompletedTask;
    }

    public Task AddRejectedScanAsync(RejectedScanRecordDto record, CancellationToken cancellationToken = default)
    {
        lock (_syncLock)
        {
            _rejected.Enqueue(record);
            while (_rejected.Count > MaxItems)
            {
                _rejected.TryDequeue(out _);
            }
        }

        return Task.CompletedTask;
    }

    public Task<IReadOnlyCollection<ScannedRecordDto>> GetLastFiveSuccessfulScansAsync(CancellationToken cancellationToken = default)
    {
        lock (_syncLock)
        {
            return Task.FromResult<IReadOnlyCollection<ScannedRecordDto>>(_successful.Reverse().ToArray());
        }
    }

    public Task<IReadOnlyCollection<RejectedScanRecordDto>> GetLastFiveRejectedScansAsync(CancellationToken cancellationToken = default)
    {
        lock (_syncLock)
        {
            return Task.FromResult<IReadOnlyCollection<RejectedScanRecordDto>>(_rejected.Reverse().ToArray());
        }
    }

    public Task<IReadOnlyCollection<ScannedRecordDto>> GetAllSuccessfulScansAsync(CancellationToken cancellationToken = default)
    {
        lock (_syncLock)
        {
            return Task.FromResult<IReadOnlyCollection<ScannedRecordDto>>(_successful.Reverse().ToArray());
        }
    }

    public Task<IReadOnlyCollection<RejectedScanRecordDto>> GetAllRejectedScansAsync(CancellationToken cancellationToken = default)
    {
        lock (_syncLock)
        {
            return Task.FromResult<IReadOnlyCollection<RejectedScanRecordDto>>(_rejected.Reverse().ToArray());
        }
    }
}