const PX_PER_MM = 96 / 25.4; export function pagePoint(x, y, rect, page, rotation) { const u = (x - rect.left) / rect.width; const v = (y - rect.top) / rect.height; const points = [[u, v], [v, 1 - u], [1 - u, 1 - v], [1 - v, u]]; const point = points[rotation / 90]; return { x: point[0] * page.width, y: point[1] * page.height }; } export function objectTransform(box, dx, dy, corner = "") { if (!corner) { return { x: dx, y: dy, scale: 1 }; } const left = corner.includes("w"); const top = corner.includes("n"); const x = left ? -dx : dx; const y = top ? -dy : dy; const minimum = Math.min(1, 1 / Math.min(box.width, box.height)); const scale = Math.max(minimum, 1 + (x * box.width + y * box.height) / (box.width ** 2 + box.height ** 2)); return { x: left ? box.width * (1 - scale) : 0, y: top ? box.height * (1 - scale) : 0, scale }; } // selectionBounds keeps same-page objects together without changing their relative positions. export function selectionBounds(items) { const x = Math.min(...items.map(item => item.x)), y = Math.min(...items.map(item => item.y)); return { x, y, width: Math.max(...items.map(item => item.x + item.width)) - x, height: Math.max(...items.map(item => item.y + item.height)) - y }; } // constrainedPoint preserves shape constraints without changing off-page geometry. export function constrainedPoint(from, to, shape, shift) { let dx = to.x - from.x, dy = to.y - from.y; if (shift && shape === "line") { const directions = [[1, 0], [1, 1], [0, 1], [-1, 1], [-1, 0], [-1, -1], [0, -1], [1, -1]]; const [x, y] = directions[(Math.round(Math.atan2(dy, dx) / (Math.PI / 4)) + 8) % 8]; const length = (dx * x + dy * y) / (x * x + y * y); dx = x * length; dy = y * length; } else if (shift) { const size = Math.max(Math.abs(dx), Math.abs(dy)); dx = (dx < 0 ? -1 : 1) * size; dy = (dy < 0 ? -1 : 1) * size; } return { x: from.x + dx, y: from.y + dy }; } // reshapeBox moves line endpoints or resizes basic shapes without scaling their stroke. export function reshapeBox(item, dx, dy, handle, shift) { const box = item.geometry; if (!dx && !dy && !shift) return { ...box }; if (item.shape === "line") { const start = { x: box.x, y: box.y }, end = { x: box.x + box.width, y: box.y + box.height }; const fixed = handle === "start" ? end : start, moving = handle === "start" ? start : end; const point = constrainedPoint(fixed, { x: moving.x + dx, y: moving.y + dy }, "line", shift); const from = handle === "start" ? point : fixed, to = handle === "start" ? fixed : point; return from.x === to.x && from.y === to.y ? null : { x: from.x, y: from.y, width: to.x - from.x, height: to.y - from.y }; } if (shift && handle.length === 2) { const change = objectTransform(box, dx, dy, handle); return { x: box.x + change.x, y: box.y + change.y, width: box.width * change.scale, height: box.height * change.scale }; } let x = box.x, y = box.y, right = x + box.width, bottom = y + box.height; const minWidth = Math.min(1, box.width), minHeight = Math.min(1, box.height); if (handle.includes("w")) x = Math.min(x + dx, right - minWidth); if (handle.includes("e")) right = Math.max(right + dx, x + minWidth); if (handle.includes("n")) y = Math.min(y + dy, bottom - minHeight); if (handle.includes("s")) bottom = Math.max(bottom + dy, y + minHeight); return { x, y, width: right - x, height: bottom - y }; } // paintShape uses the same page-space geometry for creation and endpoint previews. function paintShape(node, shape, box) { const { x, y, width, height } = box; const attributes = shape === "line" ? { x1: x, y1: y, x2: x + width, y2: y + height } : shape === "ellipse" ? { cx: x + width / 2, cy: y + height / 2, rx: width / 2, ry: height / 2 } : { x, y, width, height }; for (const [key, value] of Object.entries(attributes)) { node.setAttribute(key, value); } } export class CanvasEditor { constructor(viewer, options) { this.viewer = viewer; this.options = options; this.enabled = false; this.selected = null; this.multiple = false; this.nodes = new WeakMap(); this.pages = new WeakMap(); this.tool = ""; viewer.addEventListener("pointerdown", (event) => this.start(event)); viewer.addEventListener("pointermove", (event) => this.move(event)); viewer.addEventListener("pointerup", (event) => this.end(event)); viewer.addEventListener("pointercancel", () => this.cancel()); viewer.addEventListener("lostpointercapture", () => this.cancel()); viewer.addEventListener("keydown", (event) => this.keyDown(event)); viewer.addEventListener("keyup", (event) => this.modifierChange(event)); viewer.addEventListener("dblclick", () => { const item = this.selected; if (this.enabled && item && !item.items && !this.input && !this.options.busy()) { this.options.onEdit(item); } }); viewer.addEventListener("scroll", () => this.cancel()); window.addEventListener("blur", () => this.cancel()); window.addEventListener("resize", () => this.cancel()); } setEnabled(enabled) { this.enabled = enabled; this.viewer.classList.toggle("editing-select", enabled); if (!enabled) { this.setTool(""); this.clear(); } } setTool(tool) { this.cancel(); this.tool = tool; this.viewer.classList.toggle("editing-draw", Boolean(tool)); if (tool) { this.select(null); } this.options.onTool?.(tool); } mount(index, page, surface) { const pending = this.pendingSelection?.index === index; const selected = pending ? this.pendingSelection.ids || page.objects.slice(-1).map(item => item.id) : this.items().filter(item => item.index === index).map(item => item.id); const selection = []; this.pages.set(surface, { index, width: page.width, height: page.height }); const layer = document.createElement("div"); layer.className = "edit-layer"; for (const object of page.objects) { const node = document.createElement("div"); node.className = "edit-object"; if (object.shape === "line") { node.classList.add("edit-line"); } node.tabIndex = 0; node.setAttribute("role", "button"); node.setAttribute("aria-label", { ImageObject: "图片对象", TextObject: "文字对象", PathObject: "图形对象" }[object.type]); const item = { ...object, index, page: { width: page.width, height: page.height }, node, surface }; this.nodes.set(node, item); node.addEventListener("focus", () => this.select(item)); const handles = object.shape === "line" ? ["start", "end"] : object.shape ? ["nw", "n", "ne", "e", "se", "s", "sw", "w"] : object.type === "TextObject" ? ["nw", "ne", "e", "se", "sw", "w"] : ["nw", "ne", "sw", "se"]; for (const corner of handles) { const handle = document.createElement("span"); handle.className = `edit-handle edit-${corner}`; handle.dataset.corner = corner; node.append(handle); } this.place(item); layer.append(node); if (selected.includes(object.id)) { selection.push(item); } } surface.append(layer); if (selected.length) this.setSelection(selection); if (pending) this.pendingSelection = null; } place(item, change = { x: 0, y: 0, scale: 1 }) { if (item.items) { for (const member of item.items) this.place(member, change); return; } if (item.shape) { this.placeShape(item, { x: item.geometry.x + change.x, y: item.geometry.y + change.y, width: item.geometry.width * change.scale, height: item.geometry.height * change.scale }); return; } Object.assign(item.node.style, { left: `${(item.x + change.x) * PX_PER_MM}px`, top: `${(item.y + change.y) * PX_PER_MM}px`, width: `${item.width * change.scale * PX_PER_MM}px`, height: `${item.height * change.scale * PX_PER_MM}px`, }); } // placeShape positions basic-shape handles at their geometry rather than the padded boundary. placeShape(item, box) { const x = Math.min(box.x, box.x + box.width), y = Math.min(box.y, box.y + box.height); Object.assign(item.node.style, { left: `${x * PX_PER_MM}px`, top: `${y * PX_PER_MM}px`, width: `${Math.abs(box.width) * PX_PER_MM}px`, height: `${Math.abs(box.height) * PX_PER_MM}px`, }); if (item.shape === "line") { for (const handle of item.node.children) { const end = handle.dataset.corner === "end"; handle.style.left = `${(box.x + (end ? box.width : 0) - x) * PX_PER_MM}px`; handle.style.top = `${(box.y + (end ? box.height : 0) - y) * PX_PER_MM}px`; } } } // items returns the current selection without treating a group as a document object. items() { return this.selected?.items || (this.selected ? [this.selected] : []); } // setSelection updates object highlights and exposes one same-page selection to the toolbar. setSelection(items) { for (const item of this.items()) { item.node.classList.remove("selected", "multi-selected"); item.node.setAttribute("aria-pressed", "false"); } this.selected = items.length < 2 ? items[0] || null : { ...selectionBounds(items), items, id: items.map(item => item.id), index: items[0].index, page: items[0].page, surface: items[0].surface }; for (const item of items) { item.node.classList.add("selected"); item.node.classList.toggle("multi-selected", items.length > 1); item.node.setAttribute("aria-pressed", "true"); } this.options.onSelect(this.selected); } select(item, add = false) { if (!add || !item || this.selected && item.index !== this.selected.index) { this.setSelection(item ? [item] : []); return; } const items = this.items(); this.setSelection(items.includes(item) ? items.filter(member => member !== item) : [...items, item]); } clear() { this.closeText(); this.cancel(); this.pendingSelection = null; this.select(null); } start(event) { if (this.input) { if (event.target !== this.input.input) this.commitText(); return; } if (!this.enabled || this.options.busy() || event.button !== 0 || this.drag) { return; } if (this.tool) { this.startShape(event); return; } const node = event.target.closest(".edit-object"); if (node) { event.preventDefault(); } this.viewer.focus({ preventScroll: true }); const target = node ? this.nodes.get(node) : null; const additive = event.shiftKey || event.ctrlKey || event.metaKey || this.multiple; if (!target) { this.startMarquee(event, additive); return; } if (additive && !event.target.dataset.corner) { this.select(target, true); return; } if (!this.items().includes(target)) this.select(target); if (!node || this.options.busy()) { return; } const item = this.selected; this.drag = { item, pointerID: event.pointerId, corner: item.items ? "" : event.target.dataset.corner || "", rect: item.surface.getBoundingClientRect(), rotation: this.options.rotation(), clientX: event.clientX, clientY: event.clientY, }; if (item.shape === "line" && this.drag.corner) { Object.assign(this.drag, this.createPreview(item.surface, item.page, item.shape, { fill: false, stroke: true, strokeColor: "var(--accent)", lineWidth: item.lineWidth, })); } this.viewer.setPointerCapture(event.pointerId); } move(event) { const drag = this.drag; if (!drag || drag.pointerID !== event.pointerId) { return; } event.preventDefault(); drag.pointer = event; if (drag.shape) { this.moveShape(event, drag); return; } if (drag.marquee) { this.moveMarquee(event, drag); return; } if (!drag.change && !drag.box && Math.hypot(event.clientX - drag.clientX, event.clientY - drag.clientY) < 3) { return; } const from = pagePoint(drag.clientX, drag.clientY, drag.rect, drag.item.page, drag.rotation); const to = pagePoint(event.clientX, event.clientY, drag.rect, drag.item.page, drag.rotation); if (drag.item.type === "TextObject" && (drag.corner === "w" || drag.corner === "e")) { drag.box = reshapeBox({ geometry: drag.item }, to.x - from.x, 0, drag.corner, false); Object.assign(drag.item.node.style, { left: `${drag.box.x * PX_PER_MM}px`, width: `${drag.box.width * PX_PER_MM}px` }); return; } if (drag.item.shape && drag.corner) { drag.box = reshapeBox(drag.item, to.x - from.x, to.y - from.y, drag.corner, event.shiftKey); this.placeShape(drag.item, drag.box || drag.item.geometry); if (drag.node) paintShape(drag.node, drag.item.shape, drag.box || drag.item.geometry); return; } drag.change = objectTransform(drag.item, to.x - from.x, to.y - from.y, drag.corner); this.place(drag.item, drag.change); } end(event) { const drag = this.drag; if (!drag || drag.pointerID !== event.pointerId) { return; } this.move(event); if (drag.marquee) { this.drag = null; drag.preview.remove(); this.viewer.releasePointerCapture(drag.pointerID); return; } if (drag.shape) { this.drag = null; this.viewer.releasePointerCapture(drag.pointerID); if (drag.shape === "text") { const from = pagePoint(drag.clientX, drag.clientY, drag.rect, drag.page, drag.rotation); const x = Math.max(0, Math.min(from.x, drag.page.width - 1)); const y = Math.max(0, Math.min(from.y, drag.page.height - 1)); const box = drag.box || { x, y, width: Math.min(80, drag.page.width - x), height: 5 }; drag.preview.remove(); this.setTool(""); this.options.onDrawText(drag.page.index, box, drag.surface, drag.page); return; } if (!drag.box) { drag.preview.remove(); return; } this.setTool(""); Promise.resolve(this.options.onDraw(drag.page.index, drag.shape, drag.box, drag.style)) .finally(() => drag.preview.remove()); return; } if ((drag.item.shape || drag.item.type === "TextObject") && drag.corner && drag.box) { this.drag = null; this.viewer.releasePointerCapture(drag.pointerID); const geometry = drag.item.geometry || drag.item; const changed = Object.keys(drag.box).some((key) => drag.box[key] !== geometry[key]); const apply = drag.item.shape ? this.options.onReshape : this.options.onTextWidth; Promise.resolve(changed && apply(drag.item, drag.box)).finally(() => { drag.preview?.remove(); this.place(drag.item); }); return; } this.cancel(); if (drag.change && (drag.change.x || drag.change.y || drag.change.scale !== 1)) { this.options.onTransform(drag.item, drag.change); } } cancel() { const drag = this.drag; this.drag = null; if (drag) { drag.preview?.remove(); if (drag.marquee) this.setSelection(drag.before); if (drag.item) { this.place(drag.item); } if (this.viewer.hasPointerCapture(drag.pointerID)) { this.viewer.releasePointerCapture(drag.pointerID); } } } // startMarquee selects by page-space geometry, so rotation and zoom use the same hit tests. startMarquee(event, additive) { const surface = event.target.closest(".page-surface"), page = this.pages.get(surface); if (!page) { this.select(null); return; } event.preventDefault(); const before = this.items(); const base = additive ? before.filter(item => item.index === page.index) : []; this.setSelection(base); this.drag = { marquee: true, page, surface, before, base, ...this.createPreview(surface, page, "rectangle", { fill: true, fillColor: "var(--accent-soft)", stroke: true, strokeColor: "var(--accent)", lineWidth: 0.2 }), pointerID: event.pointerId, clientX: event.clientX, clientY: event.clientY, rect: surface.getBoundingClientRect(), rotation: this.options.rotation() }; this.viewer.setPointerCapture(event.pointerId); } // moveMarquee includes intersecting objects while preserving an additive selection. moveMarquee(event, drag) { const from = pagePoint(drag.clientX, drag.clientY, drag.rect, drag.page, drag.rotation); const to = pagePoint(event.clientX, event.clientY, drag.rect, drag.page, drag.rotation); const box = { x: Math.min(from.x, to.x), y: Math.min(from.y, to.y), width: Math.abs(to.x-from.x), height: Math.abs(to.y-from.y) }; paintShape(drag.node, "rectangle", box); if (Math.hypot(event.clientX-drag.clientX, event.clientY-drag.clientY) < 3) return; const items = [...drag.base]; for (const node of drag.surface.querySelectorAll(".edit-object")) { const item = this.nodes.get(node); if (!items.includes(item) && item.x <= box.x+box.width && item.x+item.width >= box.x && item.y <= box.y+box.height && item.y+item.height >= box.y) { items.push(item); } } this.setSelection(items); } startShape(event) { const surface = event.target.closest(".page-surface") || (this.tool !== "text" && this.nearestSurface(event)); const page = this.pages.get(surface); if (!page) { return; } event.preventDefault(); this.viewer.focus({ preventScroll: true }); const shape = this.tool; const style = this.options.drawStyle(); if (shape === "line") { style.fill = false; style.stroke = true; } this.drag = { shape, page, surface, ...this.createPreview(surface, page, shape === "text" ? "rectangle" : shape, style), style, pointerID: event.pointerId, rect: surface.getBoundingClientRect(), rotation: this.options.rotation(), clientX: event.clientX, clientY: event.clientY }; this.viewer.setPointerCapture(event.pointerId); } // nearestSurface assigns a pasteboard gesture to one mounted page for its entire duration. nearestSurface(event) { let nearest = null, distance = Infinity; for (const surface of this.viewer.querySelectorAll(".page-surface")) { if (!this.pages.has(surface)) continue; const rect = surface.getBoundingClientRect(); const next = Math.hypot(Math.max(rect.left - event.clientX, 0, event.clientX - rect.right), Math.max(rect.top - event.clientY, 0, event.clientY - rect.bottom)); if (next < distance) { nearest = surface; distance = next; } } return nearest; } // createPreview provides a temporary SVG overlay without rerendering the page during a drag. createPreview(surface, page, shape, style) { const preview = document.createElementNS("http://www.w3.org/2000/svg", "svg"); preview.classList.add("edit-preview"); preview.setAttribute("viewBox", `0 0 ${page.width} ${page.height}`); const node = document.createElementNS("http://www.w3.org/2000/svg", shape === "rectangle" ? "rect" : shape); node.setAttribute("fill", style.fill ? style.fillColor : "none"); node.setAttribute("stroke", style.stroke ? style.strokeColor : "none"); node.setAttribute("stroke-width", style.lineWidth); preview.append(node); surface.append(preview); return { preview, node }; } moveShape(event, drag) { const point = (x, y) => { const p = pagePoint(x, y, drag.rect, drag.page, drag.rotation); return drag.shape === "text" ? { x: Math.max(0, Math.min(p.x, drag.page.width)), y: Math.max(0, Math.min(p.y, drag.page.height)) } : p; }; const from = point(drag.clientX, drag.clientY); const to = constrainedPoint(from, point(event.clientX, event.clientY), drag.shape, event.shiftKey && drag.shape !== "text"); const x = Math.min(from.x, to.x), y = Math.min(from.y, to.y); const width = Math.abs(to.x - from.x), height = drag.shape === "text" ? Math.max(5, Math.abs(to.y - from.y)) : Math.abs(to.y - from.y); const valid = Math.hypot(event.clientX - drag.clientX, event.clientY - drag.clientY) >= 3 && (drag.shape === "line" ? width > 0 || height > 0 : width > 0 && height > 0); drag.box = valid ? drag.shape === "line" ? { x: from.x, y: from.y, width: to.x - from.x, height: to.y - from.y } : { x, y, width, height } : null; paintShape(drag.node, drag.shape === "text" ? "rectangle" : drag.shape, drag.shape === "line" ? { x: from.x, y: from.y, width: to.x - from.x, height: to.y - from.y } : { x, y, width, height }); } // modifierChange refreshes the preview even when Shift changes without pointer movement. modifierChange(event) { const pointer = this.drag?.pointer; if (event.key === "Shift" && pointer) { this.move({ pointerId: pointer.pointerId, clientX: pointer.clientX, clientY: pointer.clientY, shiftKey: event.shiftKey, preventDefault() {} }); } } keyDown(event) { if (event.defaultPrevented || event.target?.closest("input, textarea, select, [contenteditable]")) return; this.modifierChange(event); if (event.key === "Escape" && this.drag && !this.tool && !this.options.busy()) { event.preventDefault(); event.stopPropagation(); this.cancel(); return; } if (event.key === "Escape" && this.tool && !this.options.busy()) { event.preventDefault(); event.stopPropagation(); this.setTool(""); return; } if (this.input || !this.enabled || !this.selected || this.options.busy() || event.ctrlKey || event.metaKey || event.altKey || event.isComposing) { return; } const directions = { ArrowLeft: [-1, 0], ArrowRight: [1, 0], ArrowUp: [0, -1], ArrowDown: [0, 1] }; const edit = event.key === "Enter" || event.key === "F2"; if (event.key !== "Escape" && event.key !== "Delete" && !edit && !directions[event.key]) { return; } event.preventDefault(); event.stopPropagation(); if (event.key === "Escape") { this.drag ? this.cancel() : this.clear(); } else if (event.key === "Delete") { this.options.onDelete(this.selected); } else if (edit && !this.drag && !this.selected.items) { this.options.onEdit(this.selected); } else if (!this.drag && directions[event.key]) { const [x, y] = directions[event.key]; const [dx, dy] = [[x, y], [y, -x], [-x, -y], [-y, x]][this.options.rotation() / 90]; const step = event.shiftKey ? 10 : 1; this.options.onTransform(this.selected, { x: dx * step, y: dy * step, scale: 1 }); } } editText(item, face) { this.cancel(); this.closeText(); this.select(item); document.fonts.add(face); const input = document.createElement("textarea"); input.className = "edit-text"; input.setAttribute("aria-label", "编辑文字"); input.wrap = item.wrap ? "soft" : "off"; input.spellcheck = false; input.value = item.text; Object.assign(input.style, { left: `${item.x * PX_PER_MM}px`, top: `${item.y * PX_PER_MM}px`, width: `${(item.wrap ? item.width : Math.max(item.width, Math.min(50, item.page.width - item.x))) * PX_PER_MM + 4}px`, minHeight: `${item.height * PX_PER_MM + 4}px`, fontFamily: `"${face.family}"`, fontSize: `${item.size * PX_PER_MM}px`, lineHeight: item.paragraphHeight || item.lineHeight ? `${(item.paragraphHeight || item.lineHeight) * PX_PER_MM}px` : "normal", color: item.color, textAlign: item.align || "left", }); this.input = { input, item, face }; item.surface.append(input); const resize = () => { input.style.height = "0px"; input.style.height = `${input.scrollHeight + 2}px`; }; input.addEventListener("input", () => { resize(); this.options.onTextChange(); }); input.addEventListener("blur", () => this.commitText()); input.addEventListener("keydown", (event) => { event.stopPropagation(); if (event.isComposing || input.readOnly) { return; } if (event.key === "Escape") { event.preventDefault(); this.closeText(); this.viewer.focus({ preventScroll: true }); } else if (event.key === "Enter" && (event.ctrlKey || event.metaKey)) { event.preventDefault(); this.commitText(); } }); resize(); input.focus({ preventScroll: true }); if (!item.draft) input.select(); } async commitText() { const editing = this.input; if (!editing) return true; if (editing.input.readOnly) return false; if (editing.input.value === editing.item.text || editing.item.draft && !editing.input.value.trim()) { this.closeText(); return true; } editing.input.readOnly = true; const saved = await this.options.onCommitText(editing.item, editing.input.value); if (this.input !== editing) { return Boolean(saved); } if (saved) { this.closeText(); } else { editing.input.readOnly = false; editing.input.focus({ preventScroll: true }); } return Boolean(saved); } closeText() { const editing = this.input; this.input = null; if (editing) { editing.input.remove(); document.fonts.delete(editing.face); if (editing.item.draft && this.selected === editing.item) this.select(null); this.options.onTextChange(); } } }