using System.IO;
using AcDream.App.UI;
using AcDream.App.UI.Layout;
using DatReaderWriter;
using DatReaderWriter.Options;

namespace AcDream.App.Tests.UI.Layout;

/// <summary>
/// #382 (Campaign OP gate 4, 2026-08-11): the main chat window's four
/// floating-window indicator buttons (<c>0x10000522</c>-<c>0x10000525</c>,
/// <c>ChatWindowController</c>'s own <c>Indicator1Id</c>..<c>Indicator4Id</c>)
/// rendered NOTHING at rest — only a mouse hover revealed the correct orange
/// numbered-button art.
///
/// <para>
/// <b>ROOT CAUSE</b> (found via a reference-identity-verified live-DAT probe,
/// not a guess): the buttons' OWN construction resolves <c>ActiveState=
/// "Normal"</c> correctly (DefaultStateName="Normal", StateMedia has both
/// "Normal"/"Highlight"). The BUG fires immediately afterward, still inside
/// the SAME <c>LayoutImporter.Build</c> call: the indicator column's backing
/// panel (<c>0x10000600</c>) authors <c>PassToChildren=true</c> on its OWN
/// empty DirectState (verified live: <c>States[0xFFFFFFFF].PassToChildren ==
/// true</c>, presumably intended to route a DIFFERENT pair of named states —
/// HideDetail/ShowDetail — to an unrelated sibling, not Normal/Highlight to
/// these buttons). <c>LayoutImporter.BuildWidget</c> reapplies every
/// widget's own default state AFTER its children are attached (so retained
/// PassToChildren TABS get their authored Open/Closed child media); when the
/// PANEL's OWN reapply runs, <c>UiDatElement.TrySetRetailState</c> cascades
/// its DirectStateId to EVERY <c>IUiDatStateful</c> child — including the
/// ALREADY-CORRECTLY-RESOLVED buttons. <c>UiButton.TrySetRetailState</c>'s
/// DirectStateId branch used to accept that cascade because
/// <c>_mediaInfo.States</c> structurally carries a DirectStateId entry on
/// EVERY button (it is the property bag for ToggleBehavior/RolloverEnabled/
/// etc, independent of whether the button authors any blank sprite — see
/// <c>UiButtonTests.AddBoolProperty</c>), so <c>TryFindState(DirectStateId)</c>
/// found that entry and blanked <c>ActiveState</c> to "" even though
/// <c>StateMedia</c> has no "" key at all. A synthetic hover "fixed" it only
/// because <c>UiButtonStateMachine.RequestedState</c> resolves to the SAME
/// canonical Normal id regardless of PointerOver when RolloverEnabled is
/// false, so the NEXT <c>UpdateVisualState()</c> call (from the hover event)
/// re-picks "Normal" from <c>_availableStates</c> — the construction-time
/// blanking was a one-shot event, not a persistent "always blank" state.
/// </para>
///
/// <para>
/// <b>Fix</b> (<see cref="UiButton.TrySetRetailState"/>): the DirectStateId
/// branch now requires REAL "" media (<c>HasStateMedia("")</c>) before
/// accepting the transition — a structurally-present-but-media-less States
/// entry no longer counts. This is scoped to <c>UiButton</c> only; the
/// cascade mechanism itself and <c>LayoutImporter.BuildWidget</c>'s reapply
/// ordering are UNCHANGED, so <c>CharacterStatController</c>'s own
/// PassToChildren-driven chrome children (which rely on the SAME cascade,
/// see its own class doc) are unaffected.
/// </para>
/// </summary>
public sealed class ChatIndicatorButtonLiveMountProbeTests
{
    [Fact]
    public void IndicatorButtons_ResolveNormalStateAtRest_ThroughTheLiveImportPath()
    {
        if (Environment.GetEnvironmentVariable("ACDREAM_PROBE_LIVE_MOUNT") != "1")
            return;

        var datDir = Environment.GetEnvironmentVariable("ACDREAM_DAT_DIR")
            ?? Path.Combine(
                Environment.GetFolderPath(Environment.SpecialFolder.UserProfile),
                "Documents",
                "Asheron's Call");
        using var dats = new DatCollection(datDir, DatAccessType.Read);
        var strings = new DatStringResolver(dats);

        // The PRODUCTION main chat window layout (ChatWindowController.LayoutId),
        // not the standalone popup-catalog id VendorUiController's own doc cites
        // for a DIFFERENT purpose (the channel menu's popup catalog).
        ElementInfo? rootInfo = LayoutImporter.ImportInfos(dats, ChatWindowController.LayoutId);
        Assert.NotNull(rootInfo);

        // Confirm the root cause is still live in the DAT (documents WHY this bug
        // class exists — if this ever flips false, the fix below becomes inert but
        // harmless, so this is a documentation assertion, not a fix precondition).
        ElementInfo? parentInfo = FindInfo(rootInfo!, 0x10000600u);
        Assert.NotNull(parentInfo);
        Assert.True(
            parentInfo!.States.TryGetValue(UiStateInfo.DirectStateId, out UiStateInfo? parentDirect)
            && parentDirect.PassToChildren,
            "the indicator column's backing panel (0x10000600) no longer authors " +
            "PassToChildren on its own DirectState — the #382 root-cause premise has " +
            "changed; re-verify the fix is still needed.");

        ImportedLayout layout = LayoutImporter.Build(
            rootInfo!,
            resolve: _ => (1u, 16, 16), // fake non-zero texture handle — sprite CONTENT doesn't matter here
            datFont: null,
            fontResolve: null,
            stringResolve: strings.Resolve);

        uint[] indicatorIds = { 0x10000522u, 0x10000523u, 0x10000524u, 0x10000525u };
        foreach (uint id in indicatorIds)
        {
            UiElement? el = layout.FindElement(id);
            Assert.True(el is UiButton, $"0x{id:X8} did not build as a UiButton (was {el?.GetType().Name ?? "null"}).");
            var button = (UiButton)el!;

            // The regression: this used to read "" immediately after import, because
            // the parent panel's PassToChildren cascade (confirmed above) blanked it
            // AFTER the button's own construction had already resolved "Normal".
            Assert.Equal("Normal", button.ActiveState);

            // TrySetRetailState(Normal) — the SAME call LayoutImporter's own reapply
            // makes — must still work normally now that ToggleBehavior routes it
            // through the Selected setter.
            Assert.True(button.TrySetRetailState(UiButtonStateMachine.Normal));
            Assert.Equal("Normal", button.ActiveState);

            // A cascaded DirectStateId (what the parent's reapply actually sends)
            // must now be REJECTED rather than silently blanking an already-good
            // state — the heart of the fix.
            Assert.False(button.TrySetRetailState(UiStateInfo.DirectStateId));
            Assert.Equal("Normal", button.ActiveState);

            // Hover/leave still behave exactly as before (RolloverEnabled=false means
            // PointerOver never changes the resolved state).
            button.OnEvent(new UiEvent(0, button, UiEventType.HoverEnter));
            Assert.Equal("Normal", button.ActiveState);
            button.OnEvent(new UiEvent(0, button, UiEventType.HoverLeave));
            Assert.Equal("Normal", button.ActiveState);
        }
    }

    private static ElementInfo? FindInfo(ElementInfo node, uint id)
    {
        if (node.Id == id) return node;
        foreach (ElementInfo child in node.Children)
        {
            ElementInfo? found = FindInfo(child, id);
            if (found is not null) return found;
        }
        return null;
    }
}