using System;
using System.Collections.Generic;
using AcDream.Core.Net.Messages;
using AcDream.Core.Ui;
using AcDream.Core.World;

namespace AcDream.App.UI.Layout;

/// <summary>
/// Binds the Map tab of the retail Map/House panel (<c>gmMapUI</c>, class id
/// <c>0x10000026</c>) — <see cref="MapHousePanelController"/>'s default page.
///
/// <para>
/// Retail references: <c>gmMapUI::PostInit @0x004a1c70</c> (child
/// resolution + hotspot template setup), <c>gmMapUI::Update @0x004a1eb0</c>
/// (5 s refresh cadence — date/time text, coordinate readout, both
/// markers), <c>gmMapUI::PlaceMarkerOnMap @0x004a18b0</c> (marker centering
/// math), <c>gmMapUI::AddMapNote @0x004a1bb0</c> (town hotspot
/// instantiation + literal-string tooltip). Live-DAT byte values confirmed
/// by <c>MapHousePanelSlotProbeTests</c>: marker area
/// <c>(6,8)-(247,258)</c>, hotspot template element <c>0x100001F0</c> in
/// LayoutDesc <c>0x21000026</c>.
/// </para>
///
/// <para>
/// Coordinate math reuses <see cref="RadarCoordinates"/> (already a byte-
/// exact port of the same <c>CPlayerSystem::InqPlayerCoords @0x00560090</c>
/// formula the radar's own coordinate strip uses) rather than re-deriving
/// it — see the recon doc's "no re-port needed" note.
/// </para>
/// </summary>
public sealed class MapPageController
{
    // gmMapUI PostInit signature children (pc:171993).
    public const uint DateTimeTextId = 0x100001EBu;
    public const uint MapWidgetId = 0x100001ECu;
    public const uint PlayerIconId = 0x100001EDu;
    public const uint HouseIconId = 0x100001EEu;
    public const uint CoordinateTextId = 0x100001EFu;

    // m_pMap's own authored attrs (gmMapUI::PostInit @0x004a1c70).
    private const uint MarkerAreaX0Attr = 0x1000004Eu;
    private const uint MarkerAreaX1Attr = 0x1000004Fu;
    private const uint MarkerAreaY0Attr = 0x10000050u;
    private const uint MarkerAreaY1Attr = 0x10000051u;
    private const uint HotspotTemplateElementAttr = 0x47u;
    private const uint HotspotTemplateLayoutAttr = 0x48u;

    /// <summary>Retail's own 5 s tick cadence (<c>gmMapUI::Update</c>'s
    /// <c>m_nextUpdate = Timer::cur_time + 5.0</c>).</summary>
    public const double RefreshIntervalSeconds = 5.0;

    public sealed record Bindings(
        Func<DerethDateTime.Calendar> CurrentCalendar,
        Func<uint> PlayerCellId,
        // Slice 4 wires the real RuntimeHouseState-backed callback; defaults
        // to "no house" (matching retail's Position::IsValid == false
        // branch — the house icon starts/stays hidden) so this page works
        // standalone before that lands.
        Func<CreateObject.ServerPosition?> HousePosition,
        Func<uint, uint, UiElement?> TemplateResolver);

    private readonly UiElement? _dateTimeText;
    private readonly UiElement? _map;
    private readonly UiElement? _playerIcon;
    private readonly UiElement? _houseIcon;
    private readonly UiElement? _coordinateText;
    private readonly Bindings _bindings;
    private readonly int _markerX0, _markerX1, _markerY0, _markerY1;

    private double _nextUpdateSeconds;
    private string? _lastDateTimeText;
    private string? _lastCoordinateText;

    private MapPageController(
        UiElement? dateTimeText,
        UiElement map,
        UiElement? playerIcon,
        UiElement? houseIcon,
        UiElement? coordinateText,
        (int X0, int X1, int Y0, int Y1) markerArea,
        Bindings bindings)
    {
        _dateTimeText = dateTimeText;
        _map = map;
        _playerIcon = playerIcon;
        _houseIcon = houseIcon;
        _coordinateText = coordinateText;
        _bindings = bindings;
        (_markerX0, _markerX1, _markerY0, _markerY1) = markerArea;
    }

    /// <summary>
    /// Binds an already-built page root (<see cref="MapHousePanelController.Bind"/>
    /// resolves the page via the panel's tab table). Reads <c>m_pMap</c>'s
    /// own marker-area rect straight from the ORIGINAL <see cref="ElementInfo"/>
    /// (post-Build widgets don't carry authored int attrs), instantiates the
    /// 53 town hotspots once, and returns a controller ready for
    /// per-frame <see cref="Tick"/> polling.
    ///
    /// <para>
    /// <b>Live-DAT structural finding (MapHousePanelSlotProbeTests' follow-up
    /// dump):</b> <c>m_pMap</c> (<c>0x100001EC</c>) is itself authored as a
    /// Type-1 BUTTON (the GM click-to-teleport feature at
    /// <c>gmMapUI::ListenToElementMessage @0x004a2350</c> idMessage
    /// <c>0x1c</c>), and the player/house icons (<c>0x100001ED</c>/
    /// <c>0x100001EE</c>) are authored as ITS OWN nested children, not
    /// siblings. <see cref="UiButton.ConsumesDatChildren"/> swallows a
    /// button's dat children as skin/label parts, so they never appear in
    /// the normally-built tree — <see cref="UiElement.FindDescendant"/>
    /// against the page root always returns null for them. They're
    /// resolved the SAME way the town hotspot template is: re-imported
    /// standalone via <paramref name="bindings"/>'s
    /// <see cref="Bindings.TemplateResolver"/> against the panel's own host
    /// LayoutDesc, then attached under <c>m_pMap</c> directly — their
    /// authored local position is irrelevant since <see cref="PlaceMarker"/>
    /// overwrites it every refresh.
    /// </para>
    /// </summary>
    public static MapPageController? Bind(UiElement page, ElementInfo pageInfo, Bindings bindings)
    {
        ArgumentNullException.ThrowIfNull(page);
        ArgumentNullException.ThrowIfNull(pageInfo);
        ArgumentNullException.ThrowIfNull(bindings);

        UiElement? map = UiElement.FindDescendant(page, MapWidgetId);
        if (map is null)
        {
            Console.WriteLine($"[D.2b] Map tab: m_pMap 0x{MapWidgetId:X8} not found — Map tab will not populate.");
            return null;
        }

        ElementInfo? mapInfo = FindInfo(pageInfo, MapWidgetId);
        var markerArea = (X0: 0, X1: 0, Y0: 0, Y1: 0);
        if (mapInfo is not null)
        {
            int x0 = mapInfo.TryGetEffectiveProperty(MarkerAreaX0Attr, out var vx0) ? vx0.IntegerValue : 0;
            int x1 = mapInfo.TryGetEffectiveProperty(MarkerAreaX1Attr, out var vx1) ? vx1.IntegerValue : 0;
            int y0 = mapInfo.TryGetEffectiveProperty(MarkerAreaY0Attr, out var vy0) ? vy0.IntegerValue : 0;
            int y1 = mapInfo.TryGetEffectiveProperty(MarkerAreaY1Attr, out var vy1) ? vy1.IntegerValue : 0;
            markerArea = (x0, x1, y0, y1);
        }

        UiElement? playerIcon = ResolveSwallowedIcon(map, bindings.TemplateResolver, PlayerIconId);
        UiElement? houseIcon = ResolveSwallowedIcon(map, bindings.TemplateResolver, HouseIconId);

        var controller = new MapPageController(
            UiElement.FindDescendant(page, DateTimeTextId),
            map,
            playerIcon,
            houseIcon,
            UiElement.FindDescendant(page, CoordinateTextId),
            markerArea,
            bindings);

        controller.BuildTownMarkers(mapInfo, bindings.TemplateResolver);

        // UiText is a pull-based scrollback widget (LinesProvider), not an
        // imperative SetText target — wire the provider ONCE here to read
        // the mutable backing field Refresh() updates, matching the
        // established pattern (e.g. CharacterStatController's xpValue).
        if (controller._dateTimeText is UiText dateTimeText)
            dateTimeText.LinesProvider = () => ToLines(controller._lastDateTimeText, dateTimeText.DefaultColor);
        if (controller._coordinateText is UiText coordinateText)
            coordinateText.LinesProvider = () => ToLines(controller._lastCoordinateText, coordinateText.DefaultColor);

        // Immediate first refresh rather than waiting out the first 5 s tick.
        controller.Refresh();
        controller._nextUpdateSeconds = RefreshIntervalSeconds;
        return controller;
    }

    /// <summary>Re-resolves one of <c>m_pMap</c>'s button-swallowed nested
    /// icon children standalone (see <see cref="Bind"/>'s own doc) and
    /// attaches it under <paramref name="map"/>. Starts hidden — the first
    /// <see cref="Refresh"/> call (from <see cref="Bind"/>) decides real
    /// visibility.</summary>
    private static UiElement? ResolveSwallowedIcon(
        UiElement map, Func<uint, uint, UiElement?> templateResolver, uint iconElementId)
    {
        UiElement? icon = templateResolver(MapHousePanelController.HostLayoutId, iconElementId);
        if (icon is null)
        {
            Console.WriteLine(
                $"[D.2b] Map tab: icon 0x{iconElementId:X8} did not resolve — it will not be shown.");
            return null;
        }
        icon.Visible = false;
        map.AddChild(icon);
        return icon;
    }

    private static IReadOnlyList<UiText.Line> ToLines(string? text, System.Numerics.Vector4 color)
    {
        if (string.IsNullOrEmpty(text)) return Array.Empty<UiText.Line>();
        string[] parts = text.Split('\n');
        var lines = new UiText.Line[parts.Length];
        for (int i = 0; i < parts.Length; i++)
            lines[i] = new UiText.Line(parts[i], color);
        return lines;
    }

    /// <summary>
    /// Instantiates the 53 static town hotspots (<c>gmMapUI::AddMapNote</c>)
    /// from <c>m_pMap</c>'s own <c>0x47</c>/<c>0x48</c> template attrs. A
    /// missing template (either attr absent, or the DAT install lacks the
    /// referenced LayoutDesc/element) leaves the map usable without
    /// hotspots rather than failing the whole page — matches retail's own
    /// null-guarded <c>if (eax_10 != 0)</c> before the loop.
    /// </summary>
    private void BuildTownMarkers(ElementInfo? mapInfo, Func<uint, uint, UiElement?> templateResolver)
    {
        if (mapInfo is null) return;
        if (!mapInfo.TryGetEffectiveProperty(HotspotTemplateElementAttr, out var templateElement)) return;
        if (!mapInfo.TryGetEffectiveProperty(HotspotTemplateLayoutAttr, out var templateLayout)) return;
        if (templateLayout.UnsignedValue == 0) return;

        foreach (MapLocation loc in MapLocations.All)
        {
            UiElement? marker = templateResolver(
                (uint)templateLayout.UnsignedValue, (uint)templateElement.UnsignedValue);
            if (marker is null) continue;

            marker.Left = loc.X;
            marker.Top = loc.Y;
            marker.Width = loc.Width;
            marker.Height = loc.Height;
            // gmMapUI::AddMapNote's UIElement::SetTooltip call — a LITERAL
            // string (StringInfo::SetLiteralValue), not a DAT table lookup —
            // i.e. retail's RUNTIME m_TTText mechanism, not the authored
            // P0x49 path. UiButton.TooltipText is the exact settable seam
            // backing UiElement.GetTooltipText()'s override, which
            // RetailTooltipPresenter.ResolveTooltipText consults BEFORE the
            // authored text (closes register row TS-85's last item,
            // gmMapUI::AddMapNote @0x004A1C51). AuthoredTooltipRootElementId/
            // LayoutDid still gate the popup SKIN unconditionally even on
            // the runtime-text path — the map-note template (0x100001F0)
            // authors no individual tooltip-popup locator of its own (a
            // plain 10x10 hotspot dot), so RetailTooltipPresenter's popup
            // needs one supplied; RetailTooltipPresenter.SharedPopupSkinRootElementId/
            // SharedPopupSkinLayoutDid (see that class's own single
            // canonical citation, night-round review F10) is the same
            // proven-working skin UiItemSlot already hardcodes.
            if (marker is UiButton markerButton)
                markerButton.TooltipText = loc.Name;
            else
                // F11 (night-round review): silently skipping the runtime-
                // text write here would leave the marker's popup mounted
                // (AuthoredTooltipRootElementId/LayoutDid are still set
                // below) but genuinely EMPTY — a live-DAT template change
                // that resolves 0x100001F0 to something other than a
                // UiButton would regress every town-marker tooltip with no
                // diagnostic signal at all.
                Console.WriteLine(
                    $"[D.2b] Map tab: town marker '{loc.Name}' template "
                    + $"resolved to {marker.GetType().Name}, not UiButton — "
                    + "TooltipText cannot be set, marker will show no tooltip.");
            marker.AuthoredTooltipRootElementId = RetailTooltipPresenter.SharedPopupSkinRootElementId;
            marker.AuthoredTooltipLayoutDid = RetailTooltipPresenter.SharedPopupSkinLayoutDid;
            _map!.AddChild(marker);
        }
    }

    /// <summary>Per-frame poll, accumulating wall-clock deltas
    /// (<see cref="RetailUiRuntime.Tick"/>'s own shape) into retail's 5 s
    /// cadence — same net effect as <c>Timer::cur_time</c> comparison
    /// without needing a separate absolute clock dependency.</summary>
    public void Tick(double deltaSeconds)
    {
        _nextUpdateSeconds -= deltaSeconds;
        if (_nextUpdateSeconds > 0) return;
        _nextUpdateSeconds = RefreshIntervalSeconds;
        Refresh();
    }

    private void Refresh()
    {
        RefreshDateTime();
        RefreshCoordinatesAndPlayerMarker();
        RefreshHouseMarker();
    }

    private void RefreshDateTime()
    {
        if (_dateTimeText is null) return;
        DerethDateTime.Calendar calendar = _bindings.CurrentCalendar();
        string text = FormatDateTime(calendar);
        // gmMapUI::Update only calls SetText when the string actually
        // differs (wcscmp change-detect), not a re-stamp every 5s. The
        // LinesProvider wired in Bind() re-reads this field lazily, so
        // updating it IS the display update.
        _lastDateTimeText = text;
    }

    /// <summary>
    /// <c>"Date: %s\nTime: %s"</c> (<c>gmMapUI::Update</c>'s sprintf shape,
    /// fed by <c>GameTime::GetDateTimeString @0x005a6530</c>). Month names
    /// already match retail display text 1:1
    /// (<see cref="DerethDateTime.MonthName"/>); hour names need the
    /// "AndHalf" suffix rewritten to "-and-Half".
    /// </summary>
    internal static string FormatDateTime(DerethDateTime.Calendar calendar) =>
        $"Date: {calendar.Month} {calendar.Day}, {calendar.Year} P.Y.\nTime: {FormatHourName(calendar.Hour)}";

    private static string FormatHourName(DerethDateTime.HourName hour)
    {
        string name = hour.ToString();
        const string suffix = "AndHalf";
        return name.EndsWith(suffix, StringComparison.Ordinal)
            ? string.Concat(name.AsSpan(0, name.Length - suffix.Length), "-and-Half")
            : name;
    }

    /// <summary>
    /// <c>gmMapUI::Update @0x004a2078</c>'s gate is
    /// <c>if (m_pCoordinateText != 0 &amp;&amp; m_pPlayerLocationIcon != 0)</c>
    /// — BOTH widgets present, not "at least one". Night-round review F15:
    /// the prior <c>_coordinateText is null &amp;&amp; _playerIcon is null</c>
    /// check only skipped this method when BOTH were absent (De Morgan's:
    /// it PROCEEDED whenever EITHER was present), so a page missing one of
    /// the two would still write the other's state independently — retail
    /// updates NEITHER when either is missing (no coordinate-text write,
    /// no marker show/hide) since the whole outside/inside branch,
    /// including its inside-branch fallback, lives inside this one gate.
    /// </summary>
    private void RefreshCoordinatesAndPlayerMarker()
    {
        if (_coordinateText is null || _playerIcon is null) return;

        bool outside = RadarCoordinates.TryFromCell(_bindings.PlayerCellId(), out RadarCoordinates coords);
        if (outside)
        {
            _lastCoordinateText = coords.CombinedText;
            PlaceMarker(_playerIcon, coords.X, coords.Y);
        }
        else
        {
            // Indoors: retail clears the coordinate text and hides the
            // player marker (gmMapUI::Update's else branch,
            // m_pPlayerLocationIcon->SetVisible(0)).
            _lastCoordinateText = string.Empty;
            _playerIcon.Visible = false;
        }
    }

    /// <summary>
    /// <c>gmMapUI::Update @0x004a22a6-f6</c>: <c>Position::get_outside_cell_id
    /// (&amp;m_HousePosition) -&gt; LandDefs::gid_to_lcoord</c> -&gt; the SAME
    /// <c>(v-0x400)*0.1+0.5</c> transform <see cref="PlaceMarker"/>'s player
    /// branch uses.
    /// </summary>
    /// <remarks>
    /// Night-round review F14: this passes <c>housePosition.Value.LandblockId</c>
    /// straight to <see cref="RadarCoordinates.TryFromCell"/>, SKIPPING the
    /// <c>Position::get_outside_cell_id @0x004527b0</c> step retail's own
    /// call chain names. That function is itself BN-mangled (its final
    /// <c>return ((eax_2 - eax_2) &amp; objcell_id)</c> — an always-zero
    /// subtraction ANDed with the cell id — is textbook Binary Ninja
    /// obscuring a real conditional the raw bytes would need to
    /// disassemble to recover, the same artifact class F1/F3 hit
    /// elsewhere this round) and depends on <c>LandDefs::adjust_to_outside</c>,
    /// which takes the position's raw world XYZ (not just the landblock
    /// id) — a genuinely different, larger port than this round's other
    /// findings, not a one-line fix. Documenting the gap rather than
    /// guessing at the byte-decode (per this finding's own explicit
    /// escape hatch): <see cref="Bindings.HousePosition"/> is wired
    /// <c>() =&gt; null</c> in production today (ISSUES #413's remaining
    /// owned-house scope), so this whole method is UNREACHABLE live —
    /// there is no current behavioral gap to observe, only a latent one
    /// for whenever HousePosition gets wired to real HouseData. TODO:
    /// when that lands, port <c>Position::get_outside_cell_id</c> /
    /// <c>LandDefs::adjust_to_outside</c> (byte-decode required,
    /// <c>@0x004527b0</c> / call site <c>@0x004a2297</c>) instead of
    /// passing the raw landblock id through — for a genuinely outdoor
    /// house position this simplification is very likely already exact
    /// (an outdoor position has nothing for <c>adjust_to_outside</c> to
    /// adjust), but that has not been byte-confirmed, and an indoor
    /// house-interior recall position would need the real conversion
    /// rather than this method's current fail-safe (hide the marker,
    /// since <see cref="RadarCoordinates.TryFromCell"/> correctly refuses
    /// any cell with an envcell low word).
    /// </remarks>
    private void RefreshHouseMarker()
    {
        if (_houseIcon is null) return;

        CreateObject.ServerPosition? housePosition = _bindings.HousePosition();
        if (housePosition is null)
        {
            _houseIcon.Visible = false;
            return;
        }

        if (!RadarCoordinates.TryFromCell(housePosition.Value.LandblockId, out RadarCoordinates coords))
        {
            _houseIcon.Visible = false;
            return;
        }

        PlaceMarker(_houseIcon, coords.X, coords.Y);
    }

    /// <summary>
    /// <c>gmMapUI::PlaceMarkerOnMap @0x004a18b0</c>, ported from a direct
    /// byte-read of the PDB-paired <c>acclient.exe</c> (Binary Ninja elides
    /// the whole FPU chain to bare, operand-less <c>_ftol2()</c> calls —
    /// see <c>docs/research/named-retail/acclient_2013_pseudo_c.txt</c>
    /// lines 171827-171855 — so the pseudo-C alone under-specifies this
    /// function; capstone disassembly of the raw machine code at that VA
    /// is the ground truth here, not the BN text). The prior "center at
    /// markerX0+x" reading was WRONG — retail projects the AC display
    /// coordinate (<paramref name="x"/>/<paramref name="y"/>, range
    /// approximately ±102.4) onto the marker-area rect's pixel span via a
    /// fixed-point-style transform, not a raw pixel add:
    /// <code>
    /// X = m_x0 - w/2 - (int)( (m_x1-m_x0+1) * (x*10+1024)              * (-1/2048) )
    /// Y = m_y0 - h/2 - (int)( (m_y1-m_y0+1) * (2047-(y*10+1024))       * (-1/2048) )
    /// </code>
    /// Constants read straight from the binary's .rdata: <c>0x79bac8</c> =
    /// 10.0, <c>0x7aac78</c> = 1024.0, <c>0x7aac70</c> = -1/2048 (exactly
    /// -0.00048828125), <c>0x7aac68</c> = 2047.0. The Y axis's FSUBR
    /// (reversed subtract) is retail's north-up flip — Y increases upward
    /// on the AC coordinate system but downward in screen pixels.
    /// <c>w</c>/<c>h</c> are the icon's own <c>UIRegion::GetWidth</c>/
    /// <c>GetHeight</c> (@0x0069efe0/@0x0069eff0), halved with INTEGER
    /// (truncating) division to match retail's <c>cdq;sub;sar</c> idiom —
    /// not float division, which would drift by half a pixel on
    /// odd-sized icons. Golden case (marker area (6,8)-(247,258), 10x10
    /// icon, position 0.0N/0.0E) reproduces exactly to (122,128) center.
    /// </summary>
    private void PlaceMarker(UiElement? icon, double x, double y)
    {
        if (icon is null) return;

        (float left, float top) = ComputeMarkerPosition(
            _markerX0, _markerX1, _markerY0, _markerY1,
            (int)icon.Width, (int)icon.Height, x, y);
        icon.Left = left;
        icon.Top = top;
        icon.Visible = true;
    }

    /// <summary>
    /// The pure <c>PlaceMarkerOnMap</c> math, split out from <see cref="PlaceMarker"/>
    /// so tests can assert byte-decoded GOLDEN PIXEL values directly against
    /// the formula instead of round-tripping through the port's own output.
    /// </summary>
    internal static (float Left, float Top) ComputeMarkerPosition(
        int markerX0, int markerX1, int markerY0, int markerY1,
        int iconWidth, int iconHeight, double x, double y)
    {
        int halfWidth = iconWidth / 2;
        int halfHeight = iconHeight / 2;
        int extentX = markerX1 - markerX0 + 1;
        int extentY = markerY1 - markerY0 + 1;

        int xOffset = (int)(extentX * (x * 10.0 + 1024.0) * (-1.0 / 2048.0));
        int yOffset = (int)(extentY * (2047.0 - (y * 10.0 + 1024.0)) * (-1.0 / 2048.0));

        return (markerX0 - halfWidth - xOffset, markerY0 - halfHeight - yOffset);
    }

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