using ytLive.Helpers;
using ytLive.Services.Entitlement;

namespace ytLive.ViewModels;

/// <summary>
/// The entitlement surface: whether this session may emit output above the free budget.
///
/// <para>Deliberately a separate partial from <c>License.cs</c>: that file owns *how* a
/// licence is validated (Polar today), this one owns *what the answer means* for output.
/// Steam's DLC check and Polar's lease both collapse into <see cref="IsPremium"/>; nothing
/// downstream of <see cref="HasProOutput"/> cares which one proved it.</para>
/// </summary>
public partial class MainViewModel
{
    /// <summary>
    /// The single input to <see cref="Models.OutputProfile.Resolve"/>.
    ///
    /// <para><b>Fail closed:</b> an unresolved or unreadable licence is simply false, so a
    /// build with no entitlement emits the free profile. There is no "unknown" branch to get
    /// wrong.</para>
    ///
    /// <para><b>Developer mode never ships:</b> <see cref="DeveloperMode"/> is only ever
    /// settable inside a development build (see <see cref="DevBuild"/>), so this expression
    /// reduces to <c>IsPremium</c> in a Release binary.</para>
    /// </summary>
    public bool HasProOutput => IsPremium || DeveloperMode || _entitlement.IsPro;

    /// <summary>
    /// The entitlement rail for this session. Lifetime = Steam DLC; until the DLC app id exists it
    /// is <see cref="SteamEntitlement.NotConfigured"/>, which reads false (fail closed). Tests
    /// inject a fake through <see cref="EntitlementOverride"/>.
    /// </summary>
    private IEntitlement _entitlement = SteamEntitlement.NotConfigured();

    /// <summary>Test seam: swap the rail without a Steam client. Internal — the test assembly is
    /// the only caller, and a public setter here would be a licence bypass surface.</summary>
    internal IEntitlement EntitlementOverride
    {
        get => _entitlement;
        set
        {
            _entitlement = value;
            OnPropertyChanged(nameof(HasProOutput));
        }
    }

    private bool _developerMode;

    /// <summary>
    /// Development-only override: ignore the output budget and allow every shipped tier.
    ///
    /// <para>There is no UI to reach this in a Release build — the panel that hosts the
    /// checkbox is excluded from the Release compile — and the setter refuses the value
    /// unless <see cref="DevBuild.IsDevelopment"/> is true, so even a hand-edited settings
    /// file cannot unlock it.</para>
    /// </summary>
    public bool DeveloperMode
    {
        get => _developerMode;
        set
        {
            if (!DevBuild.IsDevelopment) return;
            if (!SetProperty(ref _developerMode, value)) return;
            OnPropertyChanged(nameof(HasProOutput));
        }
    }
}