| 1 | import { useLayoutEffect, useRef, useState } from 'react'; |
| 2 | import { STACKS_PER_SIDE } from '../game/tiles'; |
| 3 | import { |
| 4 | rhombus, |
| 5 | ringLayout, |
| 6 | RING, |
| 7 | WALL_SIDES, |
| 8 | wallStacks, |
| 9 | type Placed, |
| 10 | type Rhombus, |
| 11 | type WallProgress, |
| 12 | } from '../game/wall'; |
| 13 | |
| 14 | import { useT } from './lang'; |
| 15 | |
| 16 | /** |
| 17 | * What is left of the wall, built as a square in the middle of the table. |
| 18 | * |
| 19 | * Four staggered sides like a #, with the corners open — but a square the size |
| 20 | * of the wall *as it is dealt*, not of 144 tiles. Eighteen full-size stacks a |
| 21 | * side is longer than the middle of any ordinary window is tall, and by the |
| 22 | * time anyone is looking there is nothing like that much wall left, so it is |
| 23 | * rebuilt smaller and the tiles stay the size of the ones in your hand. What |
| 24 | * goes where is `RING` and `ringLayout` in `game/wall.ts`; this measures the |
| 25 | * middle for them and puts the answer on screen. |
| 26 | * |
| 27 | * Every stack carries its index, and that is load-bearing — `table/geometry.ts` |
| 28 | * measures these elements to build the colliders rather than restating the CSS |
| 29 | * that sizes them. |
| 30 | */ |
| 31 | export function WallRing({ state }: { state: WallProgress }) { |
| 32 | const t = useT(); |
| 33 | const ring = useRef<HTMLDivElement>(null); |
| 34 | const { opening, cell, shape } = useSquare(ring); |
| 35 | const sides = ringLayout(wallStacks(state), RING); |
| 36 | const { slide, take } = useSliding(ring, shape, cell, sides); |
| 37 | |
| 38 | return ( |
| 39 | <div |
| 40 | className="wall-ring" |
| 41 | ref={ring} |
| 42 | aria-label={t('牌牆', 'The wall')} |
| 43 | style={ |
| 44 | opening |
| 45 | ? // `--ws` is set from here rather than from the tile, because the |
| 46 | // square is the fixed thing now and the tile is what gives. |
| 47 | ({ |
| 48 | width: opening.w, |
| 49 | height: opening.h, |
| 50 | // A side is its stacks and nothing else, so there is no sum for |
| 51 | // the corners to come out of by a pixel. |
| 52 | '--wall-len': `${RING.h * cell}px`, |
| 53 | } as React.CSSProperties) |
| 54 | : undefined |
| 55 | } |
| 56 | > |
| 57 | {/* One cell, never drawn: the ring is measured in stacks, so something has |
| 58 | to be the size of a stack before any of them have been placed. */} |
| 59 | <i className="wall-probe" /> |
| 60 | {WALL_SIDES.map((cls, side) => ( |
| 61 | <div |
| 62 | className={`wall-side ${cls}`} |
| 63 | key={cls} |
| 64 | onPointerDown={take(side)} |
| 65 | style={ |
| 66 | shape |
| 67 | ? ({ |
| 68 | '--vx': `${shape.places[side].x}px`, |
| 69 | '--vy': `${shape.places[side].y}px`, |
| 70 | '--dir': `${shape.places[side].dir}deg`, |
| 71 | '--slide': `${slide[side]}px`, |
| 72 | } as React.CSSProperties) |
| 73 | : undefined |
| 74 | } |
| 75 | > |
| 76 | {sides[side].map(({ index, stack }) => ( |
| 77 | <div |
| 78 | key={index} |
| 79 | data-stack={index} |
| 80 | // The 16-tile 底牌 tail is not marked out. It is still the tail — |
| 81 | // `Stack.dead` says so and the engine ends the hand on it — but a |
| 82 | // wall on a table is one wall, not a wall with the end greyed off. |
| 83 | className={`wall-stack s${stack.count}${stack.next ? ' next' : ''}`} |
| 84 | // The layout already knows which way this stack is lying, so the |
| 85 | // physics is told rather than left to work it out off a box that |
| 86 | // has been turned. See table/geometry.ts. |
| 87 | data-angle={shape ? shape.places[side].dir : 0} |
| 88 | > |
| 89 | <i /> |
| 90 | </div> |
| 91 | ))} |
| 92 | </div> |
| 93 | ))} |
| 94 | </div> |
| 95 | ); |
| 96 | } |
| 97 | |
| 98 | /** |
| 99 | * Pushing a wall along its own line. |
| 100 | * |
| 101 | * What everybody does to a wall as it is eaten: the stacks are drawn from one |
| 102 | * end, a gap opens where the drawing is happening, and somebody shoves what is |
| 103 | * left along to close it up and keep it in reach. It moves the tiles and |
| 104 | * nothing else — the wall is the same wall in the same order and the next draw |
| 105 | * is still the next draw, exactly as washing the discards about moves no |
| 106 | * tile that anybody is counting. |
| 107 | * |
| 108 | * A wall slides only into the room it has: from where it was built to where its |
| 109 | * own stacks run out. It cannot leave its line, and it cannot climb over the |
| 110 | * one beside it. |
| 111 | * |
| 112 | * The pool is told, because a wall that has moved is a wall a thrown tile |
| 113 | * bounces off somewhere else, and the pool only re-measures when it has reason |
| 114 | * to — `invalidate` in table/pool.ts, and the listener in ui/Pool.tsx. |
| 115 | */ |
| 116 | function useSliding( |
| 117 | ring: React.RefObject<HTMLDivElement | null>, |
| 118 | shape: Rhombus | null, |
| 119 | cell: number, |
| 120 | sides: Placed[][], |
| 121 | ) { |
| 122 | const [slide, setSlide] = useState<number[]>([0, 0, 0, 0]); |
| 123 | const drag = useRef<{ side: number; ax: number; ay: number; from: number; at: number } | null>( |
| 124 | null, |
| 125 | ); |
| 126 | // What the drag needs to know, kept current without the listeners below |
| 127 | // having to be torn down and put back on every render to see it. |
| 128 | const now = useRef({ shape, cell, sides, slide }); |
| 129 | now.current = { shape, cell, sides, slide }; |
| 130 | |
| 131 | // A wall that has lost stacks has exactly that much line to be pushed along. |
| 132 | const roomOn = (side: number) => |
| 133 | Math.max(0, (STACKS_PER_SIDE - now.current.sides[side].length) * now.current.cell); |
| 134 | |
| 135 | const moved = () => ring.current?.dispatchEvent(new CustomEvent('wallmoved', { bubbles: true })); |
| 136 | |
| 137 | const take = (side: number) => (e: React.PointerEvent<HTMLDivElement>) => { |
| 138 | const place = now.current.shape?.places[side]; |
| 139 | if (!place || e.button !== 0 || roomOn(side) <= 0) return; |
| 140 | // A wall being pushed, not the table being reached into. |
| 141 | e.stopPropagation(); |
| 142 | e.preventDefault(); |
| 143 | const rad = (place.dir * Math.PI) / 180; |
| 144 | const ax = Math.cos(rad); |
| 145 | const ay = Math.sin(rad); |
| 146 | try { |
| 147 | e.currentTarget.setPointerCapture?.(e.pointerId); |
| 148 | } catch { |
| 149 | // Uncaptured still works while the pointer stays over the wall. |
| 150 | } |
| 151 | drag.current = { |
| 152 | side, |
| 153 | ax, |
| 154 | ay, |
| 155 | from: e.clientX * ax + e.clientY * ay, |
| 156 | at: now.current.slide[side], |
| 157 | }; |
| 158 | }; |
| 159 | |
| 160 | // Put on once and left alone. Registering these per render was three |
| 161 | // listeners torn down and rebuilt on every state change, for nothing. |
| 162 | useLayoutEffect(() => { |
| 163 | const move = (e: PointerEvent) => { |
| 164 | const d = drag.current; |
| 165 | if (!d) return; |
| 166 | // Only what the finger did *along* the wall counts; across it, nothing. |
| 167 | const along = e.clientX * d.ax + e.clientY * d.ay; |
| 168 | const to = Math.min(0, Math.max(-roomOn(d.side), d.at + (along - d.from))); |
| 169 | let changed = false; |
| 170 | setSlide((was) => { |
| 171 | if (was[d.side] === to) return was; |
| 172 | changed = true; |
| 173 | return was.map((v, i) => (i === d.side ? to : v)); |
| 174 | }); |
| 175 | if (changed) moved(); |
| 176 | }; |
| 177 | const up = () => { |
| 178 | if (!drag.current) return; |
| 179 | drag.current = null; |
| 180 | moved(); |
| 181 | }; |
| 182 | window.addEventListener('pointermove', move); |
| 183 | window.addEventListener('pointerup', up); |
| 184 | window.addEventListener('pointercancel', up); |
| 185 | return () => { |
| 186 | window.removeEventListener('pointermove', move); |
| 187 | window.removeEventListener('pointerup', up); |
| 188 | window.removeEventListener('pointercancel', up); |
| 189 | }; |
| 190 | // eslint-disable-next-line react-hooks/exhaustive-deps |
| 191 | }, []); |
| 192 | |
| 193 | return { slide, take }; |
| 194 | } |
| 195 | |
| 196 | interface Square { |
| 197 | /** The opening the square leaves, once there is a middle to measure. */ |
| 198 | opening: { w: number; h: number } | null; |
| 199 | /** How big a stack came out — the wall's own tile size, in px. */ |
| 200 | cell: number; |
| 201 | /** Where the four walls stand, from `rhombus`. */ |
| 202 | shape: Rhombus | null; |
| 203 | } |
| 204 | |
| 205 | /** |
| 206 | * How big to build the square, measured rather than worked out twice: how big a |
| 207 | * tile is is CSS's business, so one cell is rendered and asked how it came out, |
| 208 | * and the middle is whatever the four strips have left. Nothing here depends on |
| 209 | * the state of the hand — the square is built once for the window it is in and |
| 210 | * then eaten, so it does not close in on the discards lying inside it. |
| 211 | */ |
| 212 | function useSquare(ring: React.RefObject<HTMLDivElement | null>): Square { |
| 213 | const [square, setSquare] = useState<Square>({ opening: null, cell: 0, shape: null }); |
| 214 | |
| 215 | useLayoutEffect(() => { |
| 216 | const el = ring.current; |
| 217 | const middle = el?.parentElement; |
| 218 | const probe = el?.querySelector<HTMLElement>('.wall-probe'); |
| 219 | if (!el || !middle || !probe) return; |
| 220 | |
| 221 | // Everything the square is worked out *from*. Both observers below can be |
| 222 | // set off by this effect's own output — the probe is sized by the `--ws` it |
| 223 | // writes, and the ring's style attribute is where it writes it — so the |
| 224 | // guard is not a nicety: without it, one recompute schedules the next and |
| 225 | // the tab stops answering. Same inputs, nothing to do. |
| 226 | let last = ''; |
| 227 | |
| 228 | const read = () => { |
| 229 | const box = probe.getBoundingClientRect(); |
| 230 | if (box.width <= 0) return; |
| 231 | // What shape a stack is, is CSS's business — read it, don't restate it. |
| 232 | // Scale-free, so this is the same number however big the square came out. |
| 233 | const ratio = box.height / box.width; |
| 234 | const style = getComputedStyle(el); |
| 235 | // The corner it turns, how far round it is set, and how much daylight is |
| 236 | // left where two walls meet — in tiles, and under one of them. |
| 237 | const angle = parseFloat(style.getPropertyValue('--wall-angle')) || 90; |
| 238 | const turn = parseFloat(style.getPropertyValue('--wall-turn')) || 0; |
| 239 | const gap = parseFloat(style.getPropertyValue('--wall-gap')) || 0; |
| 240 | |
| 241 | // A wall tile is the same tile as a hand tile, so the stack is whatever |
| 242 | // size CSS made it and there is nothing to solve for. The square comes out |
| 243 | // as big as eighteen of them a side comes to, which is bigger than the |
| 244 | // middle — where it then *goes* is a separate question, and not this |
| 245 | // function's. |
| 246 | const s = box.width; |
| 247 | const from = `${middle.clientWidth}x${middle.clientHeight}/${s}/${ratio}/${angle}/${turn}/${gap}`; |
| 248 | if (from === last) return; |
| 249 | last = from; |
| 250 | |
| 251 | const shape = rhombus(STACKS_PER_SIDE * s, ratio * s, angle, turn, gap); |
| 252 | setSquare({ opening: { w: shape.open.w, h: shape.open.h }, cell: s, shape }); |
| 253 | }; |
| 254 | |
| 255 | read(); |
| 256 | // The middle, not the square: the square's own size is this effect's doing, |
| 257 | // and watching it would be watching itself. The probe is not watched for |
| 258 | // the same reason — it is `--ws` wearing a box, and `--ws` is the answer. |
| 259 | const observer = new ResizeObserver(read); |
| 260 | observer.observe(middle); |
| 261 | // The shape is three numbers on the element and none of them changes |
| 262 | // anything that has a size, so the observer above would never hear about |
| 263 | // one. `/wall.html` sets them on the ring itself, so that is what is |
| 264 | // watched — and this effect writes to that same attribute, which is what |
| 265 | // `last` is there to absorb. |
| 266 | const styled = new MutationObserver(read); |
| 267 | styled.observe(el, { attributes: true, attributeFilter: ['style'] }); |
| 268 | return () => { |
| 269 | observer.disconnect(); |
| 270 | styled.disconnect(); |
| 271 | }; |
| 272 | }, [ring]); |
| 273 | |
| 274 | return square; |
| 275 | } |