// <copyright file="IPlanRuleStore.cs" company="Stella Operations">
// Copyright (c) Stella Operations. Licensed under BUSL-1.1.
// </copyright>

using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;

namespace StellaOps.Registry.TokenService.Admin;

/// <summary>
/// Abstraction for persistent plan rule storage.
/// </summary>
public interface IPlanRuleStore
{
    /// <summary>
    /// Gets all plan rules ordered by name.
    /// </summary>
    Task<IReadOnlyList<PlanRuleDto>> GetAllAsync(CancellationToken cancellationToken = default);

    /// <summary>
    /// Gets a plan rule by ID.
    /// </summary>
    Task<PlanRuleDto?> GetByIdAsync(string id, CancellationToken cancellationToken = default);

    /// <summary>
    /// Gets a plan rule by name.
    /// </summary>
    Task<PlanRuleDto?> GetByNameAsync(string name, CancellationToken cancellationToken = default);

    /// <summary>
    /// Creates a new plan rule.
    /// </summary>
    Task<PlanRuleDto> CreateAsync(CreatePlanRequest request, string actor, CancellationToken cancellationToken = default);

    /// <summary>
    /// Updates an existing plan rule.
    /// </summary>
    Task<PlanRuleDto> UpdateAsync(string id, UpdatePlanRequest request, string actor, CancellationToken cancellationToken = default);

    /// <summary>
    /// Deletes a plan rule.
    /// </summary>
    Task<bool> DeleteAsync(string id, string actor, CancellationToken cancellationToken = default);

    /// <summary>
    /// Gets audit history for a plan.
    /// </summary>
    Task<IReadOnlyList<PlanAuditEntry>> GetAuditHistoryAsync(
        string? planId = null,
        int page = 1,
        int pageSize = 50,
        CancellationToken cancellationToken = default);
}

/// <summary>
/// Exception thrown when a plan rule version conflict occurs.
/// </summary>
public sealed class PlanVersionConflictException : System.Exception
{
    public PlanVersionConflictException(string planId, int expectedVersion, int actualVersion)
        : base($"Plan '{planId}' version conflict: expected {expectedVersion}, actual {actualVersion}")
    {
        PlanId = planId;
        ExpectedVersion = expectedVersion;
        ActualVersion = actualVersion;
    }

    public string PlanId { get; }
    public int ExpectedVersion { get; }
    public int ActualVersion { get; }
}

/// <summary>
/// Exception thrown when a plan rule is not found.
/// </summary>
public sealed class PlanNotFoundException : System.Exception
{
    public PlanNotFoundException(string planId)
        : base($"Plan '{planId}' not found")
    {
        PlanId = planId;
    }

    public string PlanId { get; }
}

/// <summary>
/// Exception thrown when a plan name already exists.
/// </summary>
public sealed class PlanNameConflictException : System.Exception
{
    public PlanNameConflictException(string name)
        : base($"Plan with name '{name}' already exists")
    {
        Name = name;
    }

    public string Name { get; }
}