using System.Collections.Concurrent;

namespace w4c_workflows.Services.Triggers;

/// <summary>
/// In-memory trigger state for lite/self-hosted mode where Redis is not available.
/// Survives only for the process lifetime (restart = re-fire once, which is safe
/// because delivery is at-least-once and the run lifecycle dedups via correlation id).
/// </summary>
public sealed class InMemoryTriggerState : ITriggerState
{
    private readonly ConcurrentDictionary<string, DateTimeOffset> _state = new();

    public Task<DateTimeOffset?> GetLastFireAsync(string tenantId, Guid workflowId, CancellationToken ct)
    {
        var key = $"{tenantId}:{workflowId}";
        return Task.FromResult(_state.TryGetValue(key, out var ts) ? (DateTimeOffset?)ts : null);
    }

    public Task SetLastFireAsync(string tenantId, Guid workflowId, DateTimeOffset at, CancellationToken ct)
    {
        var key = $"{tenantId}:{workflowId}";
        _state[key] = at;
        return Task.CompletedTask;
    }
}