1 files changed, 172 insertions, 0 deletions
diff --git a/ext/js/display/display-resizer.js b/ext/js/display/display-resizer.js
new file mode 100644
index 00000000..9fd56045
--- /dev/null
+++ b/ext/js/display/display-resizer.js
@@ -0,0 +1,172 @@
+/*
+ * Copyright (C) 2021  Yomichan Authors
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+class DisplayResizer {
+    constructor(display) {
+        this._display = display;
+        this._token = null;
+        this._handle = null;
+        this._touchIdentifier = null;
+        this._startSize = null;
+        this._startOffset = null;
+        this._eventListeners = new EventListenerCollection();
+    }
+
+    prepare() {
+        this._handle = document.querySelector('#frame-resizer-handle');
+        if (this._handle === null) { return; }
+
+        this._handle.addEventListener('mousedown', this._onFrameResizerMouseDown.bind(this), false);
+        this._handle.addEventListener('touchstart', this._onFrameResizerTouchStart.bind(this), false);
+    }
+
+    // Private
+
+    _onFrameResizerMouseDown(e) {
+        if (e.button !== 0) { return; }
+        // Don't do e.preventDefault() here; this allows mousemove events to be processed
+        // if the pointer moves out of the frame.
+        this._startFrameResize(e);
+    }
+
+    _onFrameResizerTouchStart(e) {
+        e.preventDefault();
+        this._startFrameResizeTouch(e);
+    }
+
+    _onFrameResizerMouseUp() {
+        this._stopFrameResize();
+    }
+
+    _onFrameResizerWindowBlur() {
+        this._stopFrameResize();
+    }
+
+    _onFrameResizerMouseMove(e) {
+        if ((e.buttons & 0x1) === 0x0) {
+            this._stopFrameResize();
+        } else {
+            if (this._startSize === null) { return; }
+            const {clientX: x, clientY: y} = e;
+            this._updateFrameSize(x, y);
+        }
+    }
+
+    _onFrameResizerTouchEnd(e) {
+        if (this._getTouch(e.changedTouches, this._touchIdentifier) === null) { return; }
+        this._stopFrameResize();
+    }
+
+    _onFrameResizerTouchCancel(e) {
+        if (this._getTouch(e.changedTouches, this._touchIdentifier) === null) { return; }
+        this._stopFrameResize();
+    }
+
+    _onFrameResizerTouchMove(e) {
+        if (this._startSize === null) { return; }
+        const primaryTouch = this._getTouch(e.changedTouches, this._touchIdentifier);
+        if (primaryTouch === null) { return; }
+        const {clientX: x, clientY: y} = primaryTouch;
+        this._updateFrameSize(x, y);
+    }
+
+    _startFrameResize(e) {
+        if (this._token !== null) { return; }
+
+        const {clientX: x, clientY: y} = e;
+        const token = {};
+        this._token = token;
+        this._startOffset = {x, y};
+        this._eventListeners.addEventListener(window, 'mouseup', this._onFrameResizerMouseUp.bind(this), false);
+        this._eventListeners.addEventListener(window, 'blur', this._onFrameResizerWindowBlur.bind(this), false);
+        this._eventListeners.addEventListener(window, 'mousemove', this._onFrameResizerMouseMove.bind(this), false);
+
+        const {documentElement} = document;
+        if (documentElement !== null) {
+            documentElement.dataset.isResizing = 'true';
+        }
+
+        this._initializeFrameResize(token);
+    }
+
+    _startFrameResizeTouch(e) {
+        if (this._token !== null) { return; }
+
+        const {clientX: x, clientY: y, identifier} = e.changedTouches[0];
+        const token = {};
+        this._token = token;
+        this._startOffset = {x, y};
+        this._touchIdentifier = identifier;
+        this._eventListeners.addEventListener(window, 'touchend', this._onFrameResizerTouchEnd.bind(this), false);
+        this._eventListeners.addEventListener(window, 'touchcancel', this._onFrameResizerTouchCancel.bind(this), false);
+        this._eventListeners.addEventListener(window, 'blur', this._onFrameResizerWindowBlur.bind(this), false);
+        this._eventListeners.addEventListener(window, 'touchmove', this._onFrameResizerTouchMove.bind(this), false);
+
+        const {documentElement} = document;
+        if (documentElement !== null) {
+            documentElement.dataset.isResizing = 'true';
+        }
+
+        this._initializeFrameResize(token);
+    }
+
+    async _initializeFrameResize(token) {
+        const {parentPopupId} = this._display;
+        if (parentPopupId === null) { return; }
+
+        const size = await this._display.invokeParentFrame('popup.getFrameSize', {id: parentPopupId});
+        if (this._token !== token) { return; }
+        this._startSize = size;
+    }
+
+    _stopFrameResize() {
+        if (this._token === null) { return; }
+
+        this._eventListeners.removeAllEventListeners();
+        this._startSize = null;
+        this._startOffset = null;
+        this._touchIdentifier = null;
+        this._token = null;
+
+        const {documentElement} = document;
+        if (documentElement !== null) {
+            delete documentElement.dataset.isResizing;
+        }
+    }
+
+    async _updateFrameSize(x, y) {
+        const {parentPopupId} = this._display;
+        if (parentPopupId === null) { return; }
+
+        const handleSize = this._handle.getBoundingClientRect();
+        let {width, height} = this._startSize;
+        width += x - this._startOffset.x;
+        height += y - this._startOffset.y;
+        width = Math.max(Math.max(0, handleSize.width), width);
+        height = Math.max(Math.max(0, handleSize.height), height);
+        await this._display.invokeParentFrame('popup.setFrameSize', {id: parentPopupId, width, height});
+    }
+
+    _getTouch(touchList, identifier) {
+        for (const touch of touchList) {
+            if (touch.identifier === identifier) {
+                return touch;
+            }
+        }
+        return null;
+    }
+}