#8 とりあへずは完了

frontend/src/components/NicoViewer.tsx

@@ -0,0 +1,114 @@
+import React, { useRef, useLayoutEffect, useEffect, useState, CSSProperties } from 'react'
+import axios from 'axios'
+import { Link, useNavigate, useLocation } from 'react-router-dom'
+import { API_BASE_URL } from '../config'
+
+type Props = { id:      string,
+               width:   number,
+               height:  number,
+               style?:  CSSProperties }
+
+
+const NicoViewer: React.FC = (props: Props) => {
+  const { id, width, height, style = { } } = props
+
+  const iframeRef = useRef<HTMLIFrameElement> (null)
+  const [screenWidth, setScreenWidth] = useState<CSSProperties['width']> ()
+  const [screenHeight, setScreenHeight] = useState<CSSProperties['height']> ()
+  const [isLandscape, setIsLandScape] = useState<boolean> (false)
+  const [isFullScreen, setIsFullScreen] = useState<boolean> (false)
+
+  const src = `https://embed.nicovideo.jp/watch/${id}?persistence=1&oldScript=1&referer=&from=0&allowProgrammaticFullScreen=1`;
+
+  const styleFullScreen: CSSProperties = isFullScreen ? {
+    top: 0,
+    left: isLandscape ? 0 : '100%',
+    position: 'fixed',
+    width: screenWidth,
+    height: screenHeight,
+    zIndex: 2147483647,
+    maxWidth: 'none',
+    transformOrigin: '0% 0%',
+    transform: isLandscape ? 'none' : 'rotate(90deg)',
+    WebkitTransformOrigin: '0% 0%',
+    WebkitTransform: isLandscape ? 'none' : 'rotate(90deg)',
+  } : {};
+
+  const margedStyle = {
+    border: 'none',
+    maxWidth: '100%',
+    ...style,
+    ...styleFullScreen,
+  };
+
+  useEffect(() => {
+    const onMessage = (event: MessageEvent<any>) => {
+      if (!iframeRef.current || event.source !== iframeRef.current.contentWindow) return;
+      if (event.data.eventName === 'enterProgrammaticFullScreen') {
+        setIsFullScreen(true);
+      } else if (event.data.eventName === 'exitProgrammaticFullScreen') {
+        setIsFullScreen(false);
+      }
+    };
+
+    window.addEventListener('message', onMessage);
+
+    return () => {
+      window.removeEventListener('message', onMessage);
+    };
+  }, []);
+
+  useLayoutEffect(() => {
+    if (!isFullScreen) return;
+
+    const initialScrollX = window.scrollX;
+    const initialScrollY = window.scrollY;
+    let timer: NodeJS.Timeout;
+    let ended = false;
+
+    const pollingResize = () => {
+      if (ended) return;
+
+      const isLandscape = window.innerWidth >= window.innerHeight;
+      const windowWidth = `${isLandscape ? window.innerWidth : window.innerHeight}px`;
+      const windowHeight = `${isLandscape ? window.innerHeight : window.innerWidth}px`;
+
+      setIsLandScape(isLandscape);
+      setScreenWidth(windowWidth);
+      setScreenHeight(windowHeight);
+      timer = setTimeout(startPollingResize, 200);
+    }
+
+    const startPollingResize = () => {
+      if (window.requestAnimationFrame) {
+        window.requestAnimationFrame(pollingResize);
+      } else {
+        pollingResize();
+      }
+    }
+
+    startPollingResize();
+
+    return () => {
+      clearTimeout(timer);
+      ended = true;
+      window.scrollTo(initialScrollX, initialScrollY);
+    };
+  }, [isFullScreen]);
+
+  useEffect(() => {
+    if (!isFullScreen) return;
+    window.scrollTo(0, 0);
+  }, [screenWidth, screenHeight, isFullScreen]);
+
+  return <iframe ref={iframeRef}
+                 src={src}
+                 width={width}
+                 height={height}
+                 style={margedStyle}
+                 allowFullScreen
+                 allow="autoplay" />
+}
+
+
+export default NicoViewer

frontend/src/pages/PostDetailPage.tsx

@@ -2,6 +2,7 @@ import React, { useEffect, useState } from 'react'
 import { Link, useLocation, useParams } from 'react-router-dom'
 import axios from 'axios'
 import { API_BASE_URL, SITE_TITLE } from '../config'
+import NicoViewer from '../components/NicoViewer'
 
 type Post = { id:         number
               url:        string
@@ -28,19 +29,17 @@ const PostDetailPage = () => {
 
   document.title = `${ post.url } | ${ SITE_TITLE }`
 
+  const url = new URL (post.url)
+
   return (
       <div className="p-4">
-        <h1 className="text-2xl font-bold mb-2">{post.url}</h1>
-        <img src={post.thumbnail} alt={post.url} className="mb-4 max-w-lg" />
-        <p className="mb-2">{post.description}</p>
-        <div className="text-sm text-gray-600">
-          タグ:
-          {post.tags.map(tag => (
-            <span key={tag.name} className="ml-2 px-2 py-1 bg-gray-200 rounded">
-              #{tag.name}
-            </span>
-          ))}
-        </div>
+        {url.hostname.split ('.').slice (-2).join ('.') === 'nicovideo.jp' ? (
+            <NicoViewer id={url.pathname.match (/(?<=\/watch\/)[a-zA-Z0-9]+?(?=\/|$)/)[0]}
+                        width="640"
+                        height="360" />
+            ) : (
+            <img src={post.thumbnail} alt={post.url} className="mb-4 w-full" />
+            )}
       </div>
       )
 }