From 3b4e1a865f1a114b76f355fcac818dd3404c157e Mon Sep 17 00:00:00 2001
From: Andrio Celos <AndrioCelos@users.noreply.github.com>
Date: Thu, 6 Oct 2022 10:58:41 +1100
Subject: [PATCH] Enhance keyboard controls

The board can now receive focus.
Hand buttons - arrows: move focus; Space/Enter: select card
Board - arrows: move card; R: rotate clockwise; Shift+R: rotate anticlockwise; Space/Enter: submit play; Backspace/Escape: deselect card
Either - p: toggle pass; s: toggle special attack
---
 TableturfBattleClient/index.html            |   2 +-
 TableturfBattleClient/src/Board.ts          |  56 +++++++++-
 TableturfBattleClient/src/Card.ts           |  31 +++++-
 TableturfBattleClient/src/Pages/GamePage.ts | 108 ++++++++++++++++++--
 TableturfBattleClient/tableturf.css         |   2 +-
 5 files changed, 182 insertions(+), 17 deletions(-)

diff --git a/TableturfBattleClient/index.html b/TableturfBattleClient/index.html
index 4d84495..70fc094 100644
--- a/TableturfBattleClient/index.html
+++ b/TableturfBattleClient/index.html
@@ -103,7 +103,7 @@
 				</div>
 			</div>
 			<div id="boardSection">
-				<table id="gameBoard"></table>
+				<table id="gameBoard" tabindex="0"></table>
 				<div id="redrawModal" hidden>
 					<div id="redrawBox">
 						<p>Redraw your starting hand?</p>
diff --git a/TableturfBattleClient/src/Board.ts b/TableturfBattleClient/src/Board.ts
index e7e4a43..86f79f8 100644
--- a/TableturfBattleClient/src/Board.ts
+++ b/TableturfBattleClient/src/Board.ts
@@ -14,13 +14,63 @@ class Board {
 	highlightY = NaN;
 	private highlightedCells: [x: number, y: number][] = [ ];
 
+	startSpaces: { x: number, y: number }[] = [ ];
+
 	onclick: ((x: number, y: number) => void) | null = null;
+	oncancel: (() => void) | null = null;
 
 	constructor(table: HTMLTableElement) {
 		this.table = table;
 		table.addEventListener('mouseleave', _ => {
 			if (this.autoHighlight) this.clearHighlight()
 		});
+		table.addEventListener('keydown', e => {
+			if (this.autoHighlight) {
+				switch (e.key) {
+					case 'r':
+						this.moveHighlight((x, y, r) => [x, y, r + 1], false);
+						break;
+					case 'R':
+						this.moveHighlight((x, y, r) => [x, y, r - 1], false);
+						break;
+					case 'ArrowUp':
+						this.moveHighlight((x, y, r) => [x, y - 1, r], true);
+						break;
+					case 'ArrowDown':
+						this.moveHighlight((x, y, r) => [x, y + 1, r], true);
+						break;
+					case 'ArrowLeft':
+						this.moveHighlight((x, y, r) => [x - 1, y, r], true);
+						break;
+					case 'ArrowRight':
+						this.moveHighlight((x, y, r) => [x + 1, y, r], true);
+						break;
+					case 'Enter': case ' ':
+						if (this.onclick)
+							this.onclick(this.highlightX, this.highlightY);
+						break;
+					case 'Escape': case 'Backspace':
+						if (this.oncancel)
+							this.oncancel();
+						break;
+				}
+			}
+		})
+	}
+
+	moveHighlight(move: (x: number, y: number, r: number) => [number, number, number], clamp: boolean) {
+		if (this.playerIndex == null) return;
+		if (this.highlightedCells.length == 0 || isNaN(this.highlightX) || isNaN(this.highlightY) || isNaN(this.cardRotation)) {
+			const startSpace = this.startSpaces[this.playerIndex];
+			[this.highlightX, this.highlightY, this.cardRotation] = [startSpace.x - 3, startSpace.y - 3, 0];
+		} else {
+			let [x, y, r] = move(this.highlightX, this.highlightY, this.cardRotation);
+			let clampedPosition = clamp
+				? this.cardPlaying!.clampPosition(x, y, this.grid.length, this.grid[0].length, r)
+				: { x, y };
+			[this.highlightX, this.highlightY, this.cardRotation] = [clampedPosition.x, clampedPosition.y, r];
+		}
+		this.refreshHighlight();
 	}
 
 	checkMoveLegality(playerIndex: number, card: Card, x: number, y: number, rotation: number, isSpecialAttack: boolean): string | null {
@@ -133,7 +183,7 @@ class Board {
 				trs[y].appendChild(td);
 				col.push(td);
 				td.addEventListener('mousemove', e => {
-					if (this.autoHighlight) {
+					if (this.autoHighlight && this.cardPlaying != null) {
 						const x = parseInt((e.target as HTMLTableCellElement).dataset.x!) - 3;
 						const y = parseInt((e.target as HTMLTableCellElement).dataset.y!) - 3;
 						if (x != this.highlightX || y != this.highlightY) {
@@ -144,14 +194,14 @@ class Board {
 					}
 				});
 				td.addEventListener('click', e => {
-					if (this.autoHighlight && this.onclick) {
+					if (this.autoHighlight && this.cardPlaying != null && this.onclick) {
 						const x = parseInt((e.target as HTMLTableCellElement).dataset.x!) - 3;
 						const y = parseInt((e.target as HTMLTableCellElement).dataset.y!) - 3;
 						this.onclick(x, y);
 					}
 				});
 				td.addEventListener('wheel', e => {
-					if (this.autoHighlight) {
+					if (this.autoHighlight && this.cardPlaying != null) {
 						e.preventDefault();
 						if (e.deltaY > 0) this.cardRotation++;
 						else if (e.deltaY < 0) this.cardRotation--;
diff --git a/TableturfBattleClient/src/Card.ts b/TableturfBattleClient/src/Card.ts
index 1e0c1a7..56b1735 100644
--- a/TableturfBattleClient/src/Card.ts
+++ b/TableturfBattleClient/src/Card.ts
@@ -6,6 +6,11 @@ class Card {
 	grid: Space[][];
 	size: number;
 
+	private minX: number;
+	private minY: number;
+	private maxX: number;
+	private maxY: number;
+
 	constructor(number: number, name: string, rarity: Rarity, specialCost: number, grid: Space[][]) {
 		this.number = number;
 		this.name = name;
@@ -13,14 +18,23 @@ class Card {
 		this.specialCost = specialCost;
 		this.grid = grid;
 
-		let size = 0;
+		let size = 0, minX = 3, minY = 3, maxX = 3, maxY = 3;
 		for (let y = 0; y < 8; y++) {
 			for (let x = 0; x < 8; x++) {
-				if (grid[x][y] != Space.Empty)
+				if (grid[x][y] != Space.Empty) {
 					size++;
+					minX = Math.min(minX, x);
+					minY = Math.min(minY, y);
+					maxX = Math.max(maxX, x);
+					maxY = Math.max(maxY, y);
+				}
 			}
 		}
 		this.size = size;
+		this.minX = minX;
+		this.minY = minY;
+		this.maxX = maxX;
+		this.maxY = maxY;
 	}
 
 	static fromJson(obj: any) {
@@ -35,4 +49,17 @@ class Card {
 			default: return this.grid[7 - y][x];
 		}
 	}
+
+	clampPosition(x: number, y: number, boardWidth: number, boardHeight: number, rotation: number) {
+		let x1, y1, x2, y2;
+		switch (rotation & 3) {
+			case 0: x1 = this.minX; y1 = this.minY; x2 = this.maxX; y2 = this.maxY; break;
+			case 1: x1 = 7 - this.maxY; y1 = this.minX; x2 = 7 - this.minY; y2 = this.maxX; break;
+			case 2: x1 = 7 - this.maxX; y1 = 7 - this.maxY; x2 = 7 - this.minX; y2 = 7 - this.minY; break;
+			default: x1 = this.minY; y1 = 7 - this.maxX; x2 = this.maxY; y2 = 7 - this.minX; break;
+		}
+		x = Math.min(Math.max(x, -x1), boardWidth - 1 - x2);
+		y = Math.min(Math.max(y, -y1), boardHeight - 1 - y2);
+		return { x, y };
+	}
 }
diff --git a/TableturfBattleClient/src/Pages/GamePage.ts b/TableturfBattleClient/src/Pages/GamePage.ts
index 1e2b3e1..615465c 100644
--- a/TableturfBattleClient/src/Pages/GamePage.ts
+++ b/TableturfBattleClient/src/Pages/GamePage.ts
@@ -28,8 +28,10 @@ for (let x = 0; x < 9; x++) {
 		col.push(Space.Empty);
 	cols.push(col);
 }
-cols[4][4] = Space.SpecialInactive2;
+board.startSpaces.push({ x: 4, y: 21 });
+board.startSpaces.push({ x: 4, y: 4 });
 cols[4][21] = Space.SpecialInactive1;
+cols[4][4] = Space.SpecialInactive2;
 board.resize(cols);
 
 function loadPlayers(players: Player[]) {
@@ -102,8 +104,9 @@ async function playInkAnimations(data: {
 	const inkPlaced = new Set<number>();
 	const placements = data.placements;
 	board.clearHighlight();
-	canPlay = false;
+	board.cardPlaying = null;
 	board.autoHighlight = false;
+	canPlay = false;
 	await delay(anySpecialAttacks ? 3000 : 1000);
 	for (const placement of placements) {
 		// Skip the delay when cards don't overlap.
@@ -184,11 +187,12 @@ function updateHand(cards: any[]) {
 	if (!currentGame?.me) return;
 	currentGame.me.hand = cards.map(Card.fromJson);
 	if (cards) {
-		for (const card of currentGame.me.hand) {
+		for (let i = 0; i < currentGame.me.hand.length; i++) {
+			const card = currentGame.me.hand[i];
 			const button = new CardButton('radio', card);
 			button.inputElement.name = 'handCard';
 			handButtons.push(button);
-			button.inputElement.addEventListener('change', e => {
+			button.inputElement.addEventListener('input', e => {
 				if (button.checked) {
 					for (const button2 of handButtons) {
 						if (button2 != button)
@@ -208,9 +212,40 @@ function updateHand(cards: any[]) {
 
 							board.autoHighlight = false;
 						}
+					} else {
+						board.cardPlaying = card;
+						if (isNaN(board.highlightX) || isNaN(board.highlightY)) {
+							board.highlightX = board.startSpaces[board.playerIndex!].x - 3;
+							board.highlightY = board.startSpaces[board.playerIndex!].y - 3;
+						}
+						board.cardRotation = 0;
+						board.refreshHighlight();
+						board.table.focus();
 					}
-					board.cardPlaying = card;
-					board.cardRotation = 0;
+				}
+			});
+			button.inputElement.addEventListener('keydown', e => {
+				switch (e.key) {
+					case 'ArrowUp':
+						if (i >= 2)
+							handButtons[i - 2].inputElement.focus();
+						e.preventDefault();
+						break;
+					case 'ArrowDown':
+						if (i < 2)
+							handButtons[i + 2].inputElement.focus();
+						e.preventDefault();
+						break;
+					case 'ArrowLeft':
+						if (i % 2 != 0)
+							handButtons[i - 1].inputElement.focus();
+						e.preventDefault();
+						break;
+					case 'ArrowRight':
+						if (i % 2 == 0)
+							handButtons[i + 1].inputElement.focus();
+						e.preventDefault();
+						break;
 				}
 			});
 			handContainer.appendChild(button.element);
@@ -230,12 +265,13 @@ function redrawButton_click(e: MouseEvent) {
 	redrawModal.hidden = true;
 }
 
-passButton.addEventListener('change', e => {
+function passButton_input() {
 	board.autoHighlight = !passButton.checked;
 	if (passButton.checked) {
 		specialButton.checked = false;
 		board.cardPlaying = null;
 		board.specialAttack = false;
+		board.clearHighlight();
 		for (const el of handButtons) {
 			el.enabled = true;
 			el.checked = false;
@@ -245,8 +281,10 @@ passButton.addEventListener('change', e => {
 			handButtons[i].enabled = canPlayCard[i];
 		}
 	}
-});
-specialButton.addEventListener('change', e => {
+}
+passButton.addEventListener('input', passButton_input);
+
+function specialButton_input() {
 	board.specialAttack = specialButton.checked;
 	if (specialButton.checked) {
 		passButton.checked = false;
@@ -263,7 +301,8 @@ specialButton.addEventListener('change', e => {
 				handButtons[i].checked = false;
 		}
 	}
-});
+}
+specialButton.addEventListener('input', specialButton_input);
 
 board.onclick = (x, y) => {
 	if (board.cardPlaying == null || !currentGame?.me)
@@ -308,6 +347,55 @@ board.onclick = (x, y) => {
 	}
 };
 
+board.oncancel = () => {
+	board.cardPlaying = null;
+	board.clearHighlight();
+	for (const button of handButtons) {
+		if (button.checked) {
+			button.checked = false;
+			button.inputElement.focus();
+		}
+	}
+};
+
+function focusFirstEnabledHandCard() {
+	const input = document.activeElement as HTMLInputElement;
+	if (input.name == 'handCard') {
+		if (input.disabled)
+			input.checked = false;
+		else {
+			// An enabled hand button is already active; don't move the focus.
+			return;
+		}
+	}
+	const firstEnabledButton = handButtons.find(b => b.enabled);
+	if (firstEnabledButton)
+		firstEnabledButton.inputElement.focus();
+}
+
+document.addEventListener('keydown', e => {
+	if (!sections.get('game')!.hidden) {
+		switch (e.key) {
+			case 'p':
+				if (!passButton.disabled) {
+					passButton.checked = !passButton.checked;
+					passButton_input();
+					focusFirstEnabledHandCard();
+				}
+				e.preventDefault();
+				break;
+			case 's':
+				if (!specialButton.disabled) {
+					specialButton.checked = !specialButton.checked;
+					specialButton_input();
+					focusFirstEnabledHandCard();
+				}
+				e.preventDefault();
+				break;
+		}
+	}
+});
+
 document.getElementById('resultLeaveButton')!.addEventListener('click', e => {
 	e.preventDefault();
 	document.getElementById('preGameDefaultSection')!.hidden = false;
diff --git a/TableturfBattleClient/tableturf.css b/TableturfBattleClient/tableturf.css
index 05b9ea3..c13a1ce 100644
--- a/TableturfBattleClient/tableturf.css
+++ b/TableturfBattleClient/tableturf.css
@@ -179,7 +179,7 @@ footer {
 	z-index: -2;
 	opacity: 0.25;
 }
-.card:hover:not(.checked):not(.disabled)::before {
+.card:is(:hover, :focus-within):not(.checked, .disabled)::before {
 	content: '';
 	background: grey;
 }