refactor

src/components/reader/pager/HorizontalPager.tsx

@@ -0,0 +1,147 @@
+/*
+ * Copyright (C) Contributors to the Suwayomi project
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+import makeStyles from '@mui/styles/makeStyles';
+import React, { useEffect, useRef } from 'react';
+import Page from '../Page';
+
+const useStyles = (settings: IReaderSettings) => makeStyles({
+    reader: {
+        display: 'flex',
+        flexDirection: (settings.readerType === 'ContinuesHorizontalLTR') ? 'row' : 'row-reverse',
+        justifyContent: (settings.readerType === 'ContinuesHorizontalLTR') ? 'flex-start' : 'flex-end',
+        margin: '0 auto',
+        width: 'auto',
+        height: 'auto',
+        overflowX: 'visible',
+        userSelect: 'none',
+    },
+});
+
+export default function HorizontalPager(props: IReaderProps) {
+    const {
+        pages, curPage, settings, setCurPage, prevChapter, nextChapter,
+    } = props;
+
+    const classes = useStyles(settings)();
+
+    const selfRef = useRef<HTMLDivElement>(null);
+    const pagesRef = useRef<HTMLDivElement[]>([]);
+
+    function nextPage() {
+        if (curPage < pages.length - 1) {
+            pagesRef.current[curPage + 1]?.scrollIntoView({ inline: 'center' });
+            setCurPage((page) => page + 1);
+        } else if (settings.loadNextonEnding) {
+            nextChapter();
+        }
+    }
+
+    function prevPage() {
+        if (curPage > 0) {
+            pagesRef.current[curPage - 1]?.scrollIntoView({ inline: 'center' });
+            setCurPage(curPage - 1);
+        } else if (curPage === 0) {
+            prevChapter();
+        }
+    }
+
+    function goLeft() {
+        if (settings.readerType === 'ContinuesHorizontalLTR') {
+            prevPage();
+        } else {
+            nextPage();
+        }
+    }
+
+    function goRight() {
+        if (settings.readerType === 'ContinuesHorizontalLTR') {
+            nextPage();
+        } else {
+            prevPage();
+        }
+    }
+
+    const mouseXPos = useRef<number>(0);
+
+    function dragScreen(e: MouseEvent) {
+        window.scrollBy(mouseXPos.current - e.pageX, 0);
+    }
+
+    function dragControl(e:MouseEvent) {
+        mouseXPos.current = e.pageX;
+        selfRef.current?.addEventListener('mousemove', dragScreen);
+    }
+
+    function removeDragControl() {
+        selfRef.current?.removeEventListener('mousemove', dragScreen);
+    }
+
+    function clickControl(e:MouseEvent) {
+        if (e.clientX >= window.innerWidth * 0.85) {
+            goRight();
+        } else if (e.clientX <= window.innerWidth * 0.15) {
+            goLeft();
+        }
+    }
+
+    const handleLoadNextonEnding = () => {
+        if (settings.readerType === 'ContinuesHorizontalLTR') {
+            if (window.scrollX + window.innerWidth >= document.body.scrollWidth) {
+                nextChapter();
+            }
+        } else if (settings.readerType === 'ContinuesHorizontalRTL') {
+            if (window.scrollX <= window.innerWidth) {
+                nextChapter();
+            }
+        }
+    };
+
+    useEffect(() => {
+        pagesRef.current[curPage]?.scrollIntoView({ inline: 'center' });
+    }, [settings.readerType]);
+
+    useEffect(() => {
+        selfRef.current?.addEventListener('mousedown', dragControl);
+        selfRef.current?.addEventListener('mouseup', removeDragControl);
+
+        return () => {
+            selfRef.current?.removeEventListener('mousedown', dragControl);
+            selfRef.current?.removeEventListener('mouseup', removeDragControl);
+        };
+    }, [selfRef]);
+
+    useEffect(() => {
+        if (settings.loadNextonEnding) {
+            document.addEventListener('scroll', handleLoadNextonEnding);
+        }
+        selfRef.current?.addEventListener('mousedown', clickControl);
+
+        return () => {
+            document.removeEventListener('scroll', handleLoadNextonEnding);
+            selfRef.current?.removeEventListener('mousedown', clickControl);
+        };
+    }, [selfRef, curPage]);
+
+    return (
+        <div ref={selfRef} className={classes.reader}>
+            {
+                pages.map((page) => (
+                    <Page
+                        key={page.index}
+                        index={page.index}
+                        src={page.src}
+                        onImageLoad={() => {}}
+                        setCurPage={setCurPage}
+                        settings={settings}
+                        ref={(e:HTMLDivElement) => { pagesRef.current[page.index] = e; }}
+                    />
+                ))
+            }
+        </div>
+    );
+}