@namespace CitySim
@using CitySim.Cards
@using CitySim.Match
@using CitySim.Punchboard
@using CitySim.DesignSystem
@inherits MatchPanel

<root class="hand-area @(BoundMatch?.Phase == MatchPhase.Payout ? "paying-out" : "")">
	@if (City.Multiplayer && City.LocalPlayer == null)
	{
		<div class="hand-heading">@(GameText.Get("ui.hand_bar.watching_join_the_next_match"))</div>
	}
	<div class="hand-cards">
		@if (City.LocalPlayer is { } player)
		{
			<PlotterHand><ChildContent>
				@for (var i = 0; i < player.Hand.Count; i++)
				{
					var slot = i;
					var card = CardLibrary.Get(player.Hand[i]);
					<div class="hand-slot"><PlotterCard City=@City Card=@card BuildOnly=@true SelectionSound=@false CssClass="hand-card" Selected=@(slot == City.SelectedSlot) Compact=@true Clicked=@(() => { City.SelectSlot(slot); }) Discarded=@(() => { City.DiscardSlot(slot); }) ShowDiscard=@(slot == City.SelectedSlot && City.Mode != GameMode.Sandbox) DiscardDisabled=@(!City.BoardInput || City.RenovationArmed) /></div>
				}
			</ChildContent></PlotterHand>
			@if (player.Hand.Count == 0) { <div class="empty-hand">@(GameText.Get("ui.hand_bar.hand_empty"))</div> }
		}
	</div>
	@foreach (var flight in flights)
	{
		<div class="hand-flight [email protected] @(flight.Discard ? "discard" : "placed")" style="left: @(Pb.F(flight.X))px; top: @(Pb.F(flight.Y))px; width: @(Pb.F(flight.Width))px; height: @(Pb.F(flight.Height))px; transform: rotate(@(Pb.F(flight.Rotation))deg);"><PlotterCard [email protected](flight.CardId) City=@City BuildOnly=@true CssClass="flight-face" Disabled=@true />@if (flight.Discard) { <div class="flight-piece piece-a"></div><div class="flight-piece piece-b"></div> }</div>
	}
	<div class="hand-actions">
        @if (City.SelectedCard is { } selected && BoundMatch != null && City.LocalPlayer is { } owner && BoundMatch.Settings.BuildCost(selected) > 0) { <div class="surface">@(BoundMatch.Settings.BuildCost(selected) >owner.Coins ? GameText.Get("ui.hand_bar.need_coins_to_build_you_have_keep_this_card_to_build_later", BoundMatch.Settings.BuildCost(selected), owner.Coins) : GameText.Get("ui.hand_bar.build_coins", selected.Name, BoundMatch.Settings.BuildCost(selected)))</div> }
		@if (City.RenovationArmed) { <div class="renovation-hint">@(City.RenovationReplacement == null ? GameText.Get("ui.hand_bar.renovation_select_a_building_card") : GameText.Get("ui.hand_bar.renovation_select_your_building", City.RenovationReplacement.Name))</div><PlotterButton Text=@(GameText.Get("ui.hand_bar.cancel_renovation")) Size=@(PbSize.Small) Kind=@(PbButtonKind.Ghost) Clicked=@(() => { City.Deselect(); }) /> }
		@if (!City.RenovationArmed && City.SelectedImmediateEvent && BoundMatch?.Phase == MatchPhase.Build) { <PlotterButton Text=@(GameText.Get("ui.hand_bar.play", City.SelectedCard.Name)) Clicked=@(() => { City.PlaySelectedEvent(); }) /> }
		@if (City.SelectedCardId == "land-claim" && BoundMatch?.Phase == MatchPhase.Build) { <div class="surface">@(GameText.Get("ui.hand_bar.click_an_empty_tile_to_reserve_it"))</div> }
	</div>
</root>

@code {
	record Removed(string CardId, int Slot, int Count, long Version, float At);
	sealed record Geometry(float X, float Y, float Width, float Height, float Rotation);
	sealed record Flight(int Id, string CardId, float X, float Y, float Width, float Height, float Rotation, bool Discard, float Started);
	readonly List<Flight> flights = new();
	List<string> previousHand = new();
	long previousVersion;
	Removed removed;
	(int Slot, string Card, long Version, float At, Geometry Geometry)? discardIntent;
	int nextFlight;
	protected override void Subscribe()
	{
		RememberHand();
		if (BoundMatch != null) { BoundMatch.Events.HandChanged += Changed; BoundMatch.Events.CoinsChanged += CoinsChanged; BoundMatch.Events.PhaseChanged += Phase; BoundMatch.Events.CardPlaced += Placed; BoundMatch.Events.EventPlayed += Played; BoundMatch.Events.CardDiscarded += Discarded; }
		if (City != null) { City.UiChanged += Refresh; City.DiscardRequested += DiscardRequested; }
	}
	protected override void Unsubscribe()
	{
		if (BoundMatch != null) { BoundMatch.Events.HandChanged -= Changed; BoundMatch.Events.CoinsChanged -= CoinsChanged; BoundMatch.Events.PhaseChanged -= Phase; BoundMatch.Events.CardPlaced -= Placed; BoundMatch.Events.EventPlayed -= Played; BoundMatch.Events.CardDiscarded -= Discarded; }
		if (City != null) { City.UiChanged -= Refresh; City.DiscardRequested -= DiscardRequested; }
		removed = null; discardIntent = null; flights.Clear();
	}
	void RememberHand() { previousHand = City?.LocalPlayer?.Hand.ToList() ?? new(); previousVersion = City?.LocalPlayer?.HandVersion ?? 0; }
	void DiscardRequested(int slot, string card, long version)
	{
		if (discardIntent is { } pending && pending.Version == version && Time.Now - pending.At < 3f) return;
		removed = null; discardIntent = null;
		var hand = Descendants.OfType<PlotterHand>().FirstOrDefault();
		var face = hand?.Descendants.OfType<PlotterCard>().Where(c => !c.IsDeleting).ElementAtOrDefault(slot);
		if (face == null) return;
		var size = face.Box.Rect.Size;
		if (size.x <= 0 || size.y <= 0 || ScaleToScreen <= 0) return;
		// These conversions include the face and ancestor transforms; local positions are in screen pixels.
		Vector2 Local(Vector2 p) => ScreenPositionToPanelPosition(face.PanelPositionToScreenPosition(p)) * ScaleFromScreen;
		var a = Local(new Vector2(0, 0));
		var b = Local(new Vector2(size.x, 0));
		var c = Local(new Vector2(0, size.y));
		var centre = Local(size * 0.5f);
		var width = (b - a).Length; var height = (c - a).Length;
		var rotation = MathF.Atan2(b.y - a.y, b.x - a.x) * 180f / MathF.PI;
		var geometry = new Geometry(centre.x-width*0.5f, centre.y-height*0.5f, width, height, rotation);
		discardIntent = (slot, card, version, Time.Now, geometry);
	}
	void CoinsChanged(ResourceChange change) { if (change.Player == CityGame.Me) Refresh(); }
	void Changed(Guid player)
	{
		if (player != CityGame.Me || City.LocalPlayer == null) return;
		var hand = City.LocalPlayer.Hand;
		removed = null;
		if (City.LocalPlayer.HandVersion > previousVersion && previousHand.Count == hand.Count + 1)
		{
			// A single removal must reproduce the new hand exactly, including duplicate cards.
			var slot = discardIntent is { } intent && intent.Version == previousVersion && intent.Slot >= 0 && intent.Slot< previousHand.Count && previousHand[intent.Slot] == intent.Card && previousHand.Where((_, i) => i != intent.Slot).SequenceEqual(hand) ? intent.Slot : -1;
			if (slot < 0) for (var i = 0; i < previousHand.Count; i++) if (previousHand.Where((_, n) => n != i).SequenceEqual(hand)) { slot = i; break; }
			if (slot >= 0) removed = new(previousHand[slot], slot, previousHand.Count, previousVersion, Time.Now);
		}
		RememberHand(); Refresh();
	}
	void Placed(BoardCell cell) { if (cell.Owner == CityGame.Me) Confirm(cell.CardId, false); }
	void Played(CardEventResult result) { if (result.Player == CityGame.Me) Confirm(result.CardId, false); }
	void Discarded(HandCardChange change) { if (change.Player == CityGame.Me) Confirm(change.CardId, true); }
	void Confirm(string cardId, bool discard)
	{
		if (removed == null || removed.CardId != cardId || Time.Now - removed.At > 0.5f) return;
		var card = CardLibrary.Get(cardId);
		Geometry g;
		if (discard)
		{
			if (discardIntent is not { } intent || intent.Version != removed.Version || intent.Slot != removed.Slot || intent.Card != cardId || Time.Now - intent.At > 3f) { removed = null; return; }
			g = intent.Geometry;
		}
		else
		{
			var left = 50f + (removed.Slot - (removed.Count - 1) * 0.5f) * Math.Min(20f, 80f / Math.Max(1, removed.Count));
			g = new Geometry(Box.Rect.Size.x / PlayerPreferences.UiScale * left / 100f - 85f, Box.Rect.Size.y / PlayerPreferences.UiScale - 230f, 170f, 220f, 0f);
		}
		flights.Add(new(++nextFlight, cardId, g.X, g.Y, g.Width, g.Height, g.Rotation, discard, Time.Now));
		if (discard) TabletopAudio.Switch();
		if (flights.Count > 6) flights.RemoveAt(0);
		removed = null; discardIntent = null; Refresh();
	}
	public override void Tick()
	{
		base.Tick();
		if (removed != null && discardIntent is { } intent && intent.Version == removed.Version && intent.Slot == removed.Slot && intent.Card == removed.CardId && Time.Now - intent.At < 3f) { Confirm(removed.CardId, true); discardIntent = null; }
		if (discardIntent is { } d && Time.Now - d.At > 3f) discardIntent = null;
		if (removed != null && Time.Now - removed.At > 0.5f) removed = null;
		var changed = flights.RemoveAll(f => Time.Now - f.Started >= 0.4f) > 0;
		foreach (var f in flights)
		{
			var panel = Descendants.FirstOrDefault(p => p.HasClass($"flight-{f.Id}"));
			if (panel == null) continue;
			var t = Math.Clamp((Time.Now - f.Started) / 0.4f, 0f, 1f);
			var eased = 1f - (1f-t)*(1f-t);
			var reduced = PlayerPreferences.Current.ReduceShake || PlayerPreferences.Current.ReduceFlashing;
			panel.Style.Opacity = 1f - t;
			if (f.Discard && !reduced)
			{
				panel.Descendants.FirstOrDefault(p => p.HasClass("piece-a"))?.Style.Set("transform", $"translateX({Pb.F(-45f*eased)}px) translateY({Pb.F(-35f*eased)}px) rotate({Pb.F(-100f*eased)}deg)");
				panel.Descendants.FirstOrDefault(p => p.HasClass("piece-b"))?.Style.Set("transform", $"translateX({Pb.F(50f*eased)}px) translateY({Pb.F(20f*eased)}px) rotate({Pb.F(120f*eased)}deg)");
			}
			panel.Style.Set("transform", reduced ? $"rotate({Pb.F(f.Rotation)}deg)" : $"translateY({Pb.F(f.Discard ? 55f*eased : -130f*eased)}px) rotate({Pb.F(f.Rotation + (f.Discard ? 18f*eased : -8f*eased))}deg) scale({Pb.F(1f-(f.Discard ? 0.65f : 0.35f)*eased)})");
		}
		if (changed) Refresh();
	}
	void Phase(PhaseChange phase) { if (phase.Phase != MatchPhase.Build) { flights.Clear(); removed = null; discardIntent = null; } Refresh(); }
}