using AcDream.Core.Combat;
using AcDream.UI.Abstractions.Panels.Vitals;

namespace AcDream.UI.Abstractions.Tests;

public sealed class VitalsVMTests
{
    [Fact]
    public void HealthPercent_ReturnsCombatStateValue_AfterUpdateHealth()
    {
        var combat = new CombatState();
        uint guid = 0x5000_0042u;
        combat.OnUpdateHealth(guid, 0.42f);

        var vm = new VitalsVM(combat);
        vm.SetLocalPlayerGuid(guid);

        Assert.Equal(0.42f, vm.HealthPercent, precision: 3);
    }

    [Fact]
    public void HealthPercent_ReturnsOne_WhenGuidUnknown()
    {
        var combat = new CombatState();
        var vm = new VitalsVM(combat);

        // No SetLocalPlayerGuid call — defaults to 0 which CombatState has never seen.
        Assert.Equal(1f, vm.HealthPercent);
    }

    [Fact]
    public void HealthPercent_ReturnsOne_WhenGuidSetButNeverUpdated()
    {
        var combat = new CombatState();
        var vm = new VitalsVM(combat);
        vm.SetLocalPlayerGuid(0xDEAD_BEEFu);

        Assert.Equal(1f, vm.HealthPercent);
    }

    [Fact]
    public void StaminaPercent_IsNull_ForD2aScope()
    {
        // D.2a explicitly defers Stamina until LocalPlayerState + PlayerDescription
        // wiring. When that arrives VitalsVM.StaminaPercent becomes non-null and
        // VitalsPanel starts drawing the Stam bar automatically.
        var vm = new VitalsVM(new CombatState());
        Assert.Null(vm.StaminaPercent);
    }

    [Fact]
    public void ManaPercent_IsNull_ForD2aScope()
    {
        var vm = new VitalsVM(new CombatState());
        Assert.Null(vm.ManaPercent);
    }

    [Fact]
    public void SetLocalPlayerGuid_ReroutesHealthLookup_WithoutStaleCache()
    {
        // Simulate the realistic GameWindow flow: VM is constructed pre-login
        // with GUID=0, then SetLocalPlayerGuid is called at EnterWorld.
        var combat = new CombatState();
        uint playerGuid = 0x5003_E219u;
        combat.OnUpdateHealth(playerGuid, 0.75f);

        var vm = new VitalsVM(combat);
        // Before SetLocalPlayerGuid — reads GUID=0 → returns safe 1.0.
        Assert.Equal(1f, vm.HealthPercent);

        vm.SetLocalPlayerGuid(playerGuid);
        Assert.Equal(0.75f, vm.HealthPercent, precision: 3);
    }

    [Fact]
    public void Constructor_ThrowsOnNullCombat()
    {
        Assert.Throws<ArgumentNullException>(() => new VitalsVM(null!));
    }
}