From ba1e96db26927e0cd8a64f2bc593a920f01abd92 Mon Sep 17 00:00:00 2001
From: heimoshuiyu <heimoshuiyu@gmail.com>
Date: Fri, 22 Jul 2022 11:52:06 +0800
Subject: [PATCH] add multi language support

---
 web/src/App.js                      | 216 ++++++++++++++++------------
 web/src/component/AudioPlayer.js    |  13 +-
 web/src/component/Database.js       |  18 ++-
 web/src/component/EditReview.js     |  14 +-
 web/src/component/EditTag.js        |  22 +--
 web/src/component/FeedbackPage.js   |  15 +-
 web/src/component/FileDialog.js     |  11 +-
 web/src/component/FileInfo.js       |  42 +++---
 web/src/component/FilesInFolder.js  |  15 +-
 web/src/component/FilesTable.js     |   7 +-
 web/src/component/FoldersTable.js   |   7 +-
 web/src/component/GetRandomFiles.js |   8 +-
 web/src/component/Login.js          |  16 ++-
 web/src/component/Manage.js         |  39 +++--
 web/src/component/ManageUser.js     |  29 ++--
 web/src/component/Register.js       |  26 ++--
 web/src/component/ReviewEntry.js    |  15 +-
 web/src/component/ReviewPage.js     |   5 +-
 web/src/component/SearchFiles.js    |  14 +-
 web/src/component/SearchFolders.js  |  14 +-
 web/src/component/Share.js          |  10 +-
 web/src/component/Tags.js           |  21 +--
 web/src/component/UserProfile.js    |  20 +--
 web/src/translate/index.js          |  44 ++++++
 web/src/translate/zh_CN.js          | 105 ++++++++++++++
 25 files changed, 494 insertions(+), 252 deletions(-)
 create mode 100644 web/src/translate/index.js
 create mode 100644 web/src/translate/zh_CN.js

diff --git a/web/src/App.js b/web/src/App.js
index ec5468a..5c1e2bf 100644
--- a/web/src/App.js
+++ b/web/src/App.js
@@ -19,105 +19,135 @@ import UserStatus from "./component/UserStatus";
 import ReviewPage from "./component/ReviewPage";
 import UserProfile from "./component/UserProfile";
 import FeedbackPage from "./component/FeedbackPage";
-import { useState } from "react";
+import { useEffect, useState } from "react";
+import { Tr, langCodeContext, LANG_OPTIONS } from "./translate";
 
 function App() {
   const [playingFile, setPlayingFile] = useState({});
   const [user, setUser] = useState({});
+  const [langCode, setLangCode] = useState("en_US");
+
+  // select language
+  useEffect(() => {
+    const browserCode = window.navigator.language;
+    for (const key in LANG_OPTIONS) {
+      for (const i in LANG_OPTIONS[key].matches) {
+        const code = LANG_OPTIONS[key].matches[i];
+        if (code === browserCode) {
+          setLangCode(key);
+          return;
+        }
+      }
+    }
+    // fallback to english
+    setLangCode('en-US');
+  }, []);
+
   return (
     <div className="base">
-      <Router>
-        <header className="header">
-          <h3 className="title">
-            <img src="favicon.png" alt="logo" className="logo" />
-            <span className="title-text">MSW Open Music Project</span>
-            <UserStatus user={user} setUser={setUser} />
-          </h3>
-          <nav className="nav">
-            <NavLink to="/" className="nav-link">
-              Feeling luckly
-            </NavLink>
-            <NavLink to="/files" className="nav-link">
-              Files
-            </NavLink>
-            <NavLink to="/folders" className="nav-link">
-              Folders
-            </NavLink>
-            <NavLink to="/manage" className="nav-link">
-              Manage
-            </NavLink>
-          </nav>
-        </header>
-        <main>
-          <Routes>
-            <Route
-              index
-              path="/"
-              element={<GetRandomFiles setPlayingFile={setPlayingFile} />}
-            />
-            <Route
-              path="/files"
-              element={<SearchFiles setPlayingFile={setPlayingFile} />}
-            />
-            <Route
-              path="/folders"
-              element={<SearchFolders setPlayingFile={setPlayingFile} />}
-            />
-            <Route
-              path="/folders/:id"
-              element={<FilesInFolder setPlayingFile={setPlayingFile} />}
-            />
-            <Route
-              path="/manage"
-              element={<Manage user={user} setUser={setUser} />}
-            />
-            <Route
-              path="/manage/feedbacks"
-              element={<FeedbackPage user={user} />}
-            />
-            <Route
-              path="/manage/login"
-              element={<Login user={user} setUser={setUser} />}
-            />
-            <Route
-              path="/manage/register"
-              element={<Register user={user} setUser={setUser} />}
-            />
-            <Route path="/manage/tags" element={<Tags user={user} />} />
-            <Route path="/manage/tags/:id" element={<EditTag user={user} />} />
-            <Route
-              path="/manage/reviews/:id"
-              element={<EditReview user={user} />}
-            />
-            <Route
-              path="/manage/users"
-              element={<ManageUser user={user} setUser={setUser} />}
-            />
-            <Route
-              path="/manage/users/:id"
-              element={<UserProfile user={user} setUser={setUser} />}
-            />
-            <Route
-              path="/files/:id"
-              element={<FileInfo setPlayingFile={setPlayingFile} />}
-            />
-            <Route
-              path="/files/:id/share"
-              element={<Share setPlayingFile={setPlayingFile} />}
-            />
-            <Route
-              path="/files/:id/review"
-              element={
-                <ReviewPage user={user} setPlayingFile={setPlayingFile} />
-              }
-            />
-          </Routes>
-        </main>
-        <AudioPlayer
-          playingFile={playingFile}
-          setPlayingFile={setPlayingFile}
-        />
-      </Router>
+      <langCodeContext.Provider value={{ langCode, setLangCode }}>
+        <Router>
+          <header className="header">
+            <h3 className="title">
+              <img src="favicon.png" alt="logo" className="logo" />
+              <span className="title-text">MSW Open Music Project</span>
+              <UserStatus user={user} setUser={setUser} />
+            </h3>
+            <nav className="nav">
+              <NavLink to="/" className="nav-link">
+                {Tr("Feeling luckly")}
+              </NavLink>
+              <NavLink to="/files" className="nav-link">
+                {Tr("Files")}
+              </NavLink>
+              <NavLink to="/folders" className="nav-link">
+                {Tr("Folders")}
+              </NavLink>
+              <NavLink to="/manage" className="nav-link">
+                {Tr("Manage")}
+              </NavLink>
+            </nav>
+          </header>
+          <main>
+            <Routes>
+              <Route
+                index
+                path="/"
+                element={<GetRandomFiles setPlayingFile={setPlayingFile} />}
+              />
+              <Route
+                path="/files"
+                element={<SearchFiles setPlayingFile={setPlayingFile} />}
+              />
+              <Route
+                path="/folders"
+                element={<SearchFolders setPlayingFile={setPlayingFile} />}
+              />
+              <Route
+                path="/folders/:id"
+                element={<FilesInFolder setPlayingFile={setPlayingFile} />}
+              />
+              <Route
+                path="/manage"
+                element={
+                  <Manage
+                    user={user}
+                    setUser={setUser}
+                    setLangCode={setLangCode}
+                  />
+                }
+              />
+              <Route
+                path="/manage/feedbacks"
+                element={<FeedbackPage user={user} />}
+              />
+              <Route
+                path="/manage/login"
+                element={<Login user={user} setUser={setUser} />}
+              />
+              <Route
+                path="/manage/register"
+                element={<Register user={user} setUser={setUser} />}
+              />
+              <Route path="/manage/tags" element={<Tags user={user} />} />
+              <Route
+                path="/manage/tags/:id"
+                element={<EditTag user={user} />}
+              />
+              <Route
+                path="/manage/reviews/:id"
+                element={<EditReview user={user} />}
+              />
+              <Route
+                path="/manage/users"
+                element={<ManageUser user={user} setUser={setUser} />}
+              />
+              <Route
+                path="/manage/users/:id"
+                element={<UserProfile user={user} setUser={setUser} />}
+              />
+              <Route
+                path="/files/:id"
+                element={<FileInfo setPlayingFile={setPlayingFile} />}
+              />
+              <Route
+                path="/files/:id/share"
+                element={<Share setPlayingFile={setPlayingFile} />}
+              />
+              <Route
+                path="/files/:id/review"
+                element={
+                  <ReviewPage user={user} setPlayingFile={setPlayingFile} />
+                }
+              />
+            </Routes>
+          </main>
+          <AudioPlayer
+            playingFile={playingFile}
+            setPlayingFile={setPlayingFile}
+          />
+        </Router>
+      </langCodeContext.Provider>
     </div>
   );
 }
diff --git a/web/src/component/AudioPlayer.js b/web/src/component/AudioPlayer.js
index 8397ab4..6f10126 100644
--- a/web/src/component/AudioPlayer.js
+++ b/web/src/component/AudioPlayer.js
@@ -3,6 +3,7 @@ import { useNavigate } from "react-router";
 import { CalcReadableFilesizeDetail } from "./Common";
 import FfmpegConfig from "./FfmpegConfig";
 import FileDialog from "./FileDialog";
+import { Tr } from "../translate";
 
 function AudioPlayer(props) {
   // props.playingFile
@@ -67,7 +68,7 @@ function AudioPlayer(props) {
 
   return (
     <footer className="vertical">
-      <h5>Player status</h5>
+      <h5>{Tr("Player status")}</h5>
       {props.playingFile.id && (
         <span>
           <FileDialog
@@ -105,7 +106,7 @@ function AudioPlayer(props) {
                 props.setPlayingFile({});
               }}
             >
-              Stop
+              {Tr("Stop")}
             </button>
           )}
         </span>
@@ -138,7 +139,7 @@ function AudioPlayer(props) {
             );
           }}
         >
-          Stop Timer
+          {Tr("Stop Timer")}
         </button>
       </span>
 
@@ -149,7 +150,7 @@ function AudioPlayer(props) {
             onChange={(event) => setLoop(event.target.checked)}
             type="checkbox"
           />
-          <label>Loop</label>
+          <label>{Tr("Loop")}</label>
         </span>
 
         <span>
@@ -158,7 +159,7 @@ function AudioPlayer(props) {
             onChange={(event) => setRaw(event.target.checked)}
             type="checkbox"
           />
-          <label>Raw</label>
+          <label>{Tr("Raw")}</label>
         </span>
 
         {!raw && (
@@ -168,7 +169,7 @@ function AudioPlayer(props) {
               onChange={(event) => setPrepare(event.target.checked)}
               type="checkbox"
             />
-            <label>Prepare</label>
+            <label>{Tr("Prepare")}</label>
           </span>
         )}
       </span>
diff --git a/web/src/component/Database.js b/web/src/component/Database.js
index 75f736d..ac2a4e9 100644
--- a/web/src/component/Database.js
+++ b/web/src/component/Database.js
@@ -1,11 +1,15 @@
-import { useState, useEffect } from "react";
+import { useState, useEffect, useContext } from "react";
+import { Tr, tr, langCodeContext } from "../translate";
 
 function Database() {
   const [walkPath, setWalkPath] = useState("");
-  const [patternString, setPatternString] = useState("wav flac mp3 ogg m4a mka");
+  const [patternString, setPatternString] = useState(
+    "wav flac mp3 ogg m4a mka"
+  );
   const [tags, setTags] = useState([]);
   const [selectedTags, setSelectedTags] = useState([]);
   const [updating, setUpdating] = useState(false);
+  const { langCode } = useContext(langCodeContext);
 
   function getTags() {
     fetch("/api/v1/get_tags")
@@ -60,21 +64,21 @@ function Database() {
   }
   return (
     <div>
-      <h3>Update Database</h3>
+      <h3>{Tr("Update Database")}</h3>
       <input
         type="text"
         value={walkPath}
-        placeholder="walk path"
+        placeholder={tr("walk path", langCode)}
         onChange={(e) => setWalkPath(e.target.value)}
       />
       <input
         type="text"
         value={patternString}
-        placeholder="pattern wav flac mp3"
+        placeholder={tr("pattern wav flac mp3", langCode)}
         onChange={(e) => setPatternString(e.target.value)}
       />
       <div>
-        <h4>Tags</h4>
+        <h4>{Tr("Tags")}</h4>
         {tags.map((tag) => (
           <div key={tag.id}>
             <input
@@ -101,7 +105,7 @@ function Database() {
         }}
         disabled={updating}
       >
-        {updating ? "Updating..." : "Update Database"}
+        {updating ? Tr("Updating...") : Tr("Update Database")}
       </button>
     </div>
   );
diff --git a/web/src/component/EditReview.js b/web/src/component/EditReview.js
index bf1fb70..11e7ad8 100644
--- a/web/src/component/EditReview.js
+++ b/web/src/component/EditReview.js
@@ -1,9 +1,11 @@
-import { useEffect, useState } from "react";
+import { useContext, useEffect, useState } from "react";
 import { useParams, useNavigate } from "react-router";
+import { tr, Tr, langCodeContext } from "../translate";
 
 function SingleReview() {
   let params = useParams();
   let navigate = useNavigate();
+  const { langCode } = useContext(langCodeContext)
 
   const [review, setReview] = useState({
     id: "",
@@ -50,7 +52,7 @@ function SingleReview() {
         if (data.error) {
           alert(data.error);
         } else {
-          alert("Review updated!");
+          alert(tr("Review updated", langCode));
           navigate(-1);
         }
       });
@@ -71,7 +73,7 @@ function SingleReview() {
         if (data.error) {
           alert(data.error);
         } else {
-          alert("Review deleted!");
+          alert(tr("Review deleted", langCode));
           navigate(-1);
         }
       });
@@ -83,14 +85,14 @@ function SingleReview() {
 
   return (
     <div className="page">
-      <h3>Edit Review</h3>
+      <h3>{Tr("Edit Review")}</h3>
       <textarea
         value={review.content}
         onChange={(e) => setReview({ ...review, content: e.target.value })}
       ></textarea>
       <div>
-        <button onClick={() => deleteReview()}>Delete</button>
-        <button onClick={() => save()}>Save</button>
+        <button onClick={() => deleteReview()}>{Tr("Delete")}</button>
+        <button onClick={() => save()}>{Tr("Save")}</button>
       </div>
     </div>
   );
diff --git a/web/src/component/EditTag.js b/web/src/component/EditTag.js
index 02ece18..2cc3637 100644
--- a/web/src/component/EditTag.js
+++ b/web/src/component/EditTag.js
@@ -1,9 +1,11 @@
-import { useState, useEffect } from "react";
+import { useState, useEffect, useContext } from "react";
 import { useParams, useNavigate } from "react-router";
+import { tr, Tr, langCodeContext } from "../translate";
 
 function EditTag() {
   let params = useParams();
   let navigate = useNavigate();
+  const { langCode } = useContext(langCodeContext);
 
   const [tag, setTag] = useState({
     id: "",
@@ -54,7 +56,7 @@ function EditTag() {
         if (data.error) {
           alert(data.error);
         } else {
-          alert("Tag updated successfully");
+          alert(tr("Tag updated successfully", langCode));
           refreshTagInfo();
         }
       });
@@ -79,7 +81,7 @@ function EditTag() {
         if (data.error) {
           alert(data.error);
         } else {
-          alert("Tag deleted successfully");
+          alert(tr("Tag deleted successfully", langCode));
           navigate(-1);
         }
       });
@@ -87,9 +89,9 @@ function EditTag() {
 
   return (
     <div className="page">
-      <h3>Edit Tag</h3>
+      <h3>{Tr("Edit Tag")}</h3>
       <div>
-        <label htmlFor="id">ID</label>
+        <label htmlFor="id">{Tr("ID")}</label>
         <input
           type="text"
           disabled
@@ -98,7 +100,7 @@ function EditTag() {
           value={tag.id}
           onChange={(e) => setTag({ ...tag, id: e.target.value })}
         />
-        <label htmlFor="name">Created By</label>
+        <label htmlFor="name">{Tr("Created by")}</label>
         <input
           type="text"
           disabled
@@ -115,7 +117,7 @@ function EditTag() {
             })
           }
         />
-        <label htmlFor="name">Name</label>
+        <label htmlFor="name">{Tr("Name")}</label>
         <input
           type="text"
           name="name"
@@ -123,15 +125,15 @@ function EditTag() {
           value={tag.name}
           onChange={(e) => setTag({ ...tag, name: e.target.value })}
         />
-        <label htmlFor="description">Description</label>
+        <label htmlFor="description">{Tr("Description")}</label>
         <textarea
           name="description"
           id="description"
           value={tag.description}
           onChange={(e) => setTag({ ...tag, description: e.target.value })}
         />
-        <button onClick={deleteTag}>Delete</button>
-        <button onClick={() => updateTagInfo()}>Save</button>
+        <button onClick={deleteTag}>{Tr("Delete")}</button>
+        <button onClick={() => updateTagInfo()}>{Tr("Save")}</button>
       </div>
     </div>
   );
diff --git a/web/src/component/FeedbackPage.js b/web/src/component/FeedbackPage.js
index ce7d922..2e0413a 100644
--- a/web/src/component/FeedbackPage.js
+++ b/web/src/component/FeedbackPage.js
@@ -1,6 +1,7 @@
 import { useState, useEffect } from "react";
 import { Link } from "react-router-dom";
 import { convertIntToDateTime } from "./Common";
+import { Tr } from "../translate";
 
 function FeedbackPage() {
   const [content, setContext] = useState("");
@@ -45,17 +46,17 @@ function FeedbackPage() {
 
   return (
     <div className="page">
-      <h3>Feedback</h3>
+      <h3>{Tr("Feedbacks")}</h3>
       <textarea value={content} onChange={(e) => setContext(e.target.value)} />
-      <button onClick={() => submitFeedback()}>Submit</button>
+      <button onClick={() => submitFeedback()}>{Tr("Submit")}</button>
       <div>
         <table>
           <thead>
             <tr>
-              <th>User</th>
-              <th>Feedback</th>
-              <th>Date</th>
-              <th>Action</th>
+              <th>{Tr("User")}</th>
+              <th>{Tr("Feedback")}</th>
+              <th>{Tr("Date")}</th>
+              <th>{Tr("Action")}</th>
             </tr>
           </thead>
           <tbody>
@@ -90,7 +91,7 @@ function FeedbackPage() {
                         });
                     }}
                   >
-                    Delete
+                    {Tr("Delete")}
                   </button>
                 </td>
               </tr>
diff --git a/web/src/component/FileDialog.js b/web/src/component/FileDialog.js
index 5085619..13b4965 100644
--- a/web/src/component/FileDialog.js
+++ b/web/src/component/FileDialog.js
@@ -1,4 +1,5 @@
 import { useNavigate } from "react-router";
+import { Tr } from "../translate";
 
 function FileDialog(props) {
   // props.showStatus
@@ -23,9 +24,9 @@ function FileDialog(props) {
         {props.file.filename}
       </p>
       <p>
-        Play: play using browser player.
+        {Tr("Play: play using browser player.")}
         <br />
-        Info for more actions.
+        {Tr("Info for more actions.")}
       </p>
       <button
         onClick={() => {
@@ -33,7 +34,7 @@ function FileDialog(props) {
           props.setShowStatus(false);
         }}
       >
-        Info
+        {Tr("Info")}
       </button>
       <button
         onClick={() => {
@@ -41,9 +42,9 @@ function FileDialog(props) {
           props.setShowStatus(false);
         }}
       >
-        Play
+        {Tr("Play")}
       </button>
-      <button onClick={() => props.setShowStatus(false)}>Close</button>
+      <button onClick={() => props.setShowStatus(false)}>{Tr("Close")}</button>
     </dialog>
   );
 }
diff --git a/web/src/component/FileInfo.js b/web/src/component/FileInfo.js
index 9550695..7cdb13f 100644
--- a/web/src/component/FileInfo.js
+++ b/web/src/component/FileInfo.js
@@ -1,5 +1,6 @@
 import { useNavigate, useParams } from "react-router";
-import { useEffect, useState } from "react";
+import { useContext, useEffect, useState } from "react";
+import { Tr, tr, langCodeContext } from "../translate";
 
 function FileInfo(props) {
   let navigate = useNavigate();
@@ -14,6 +15,7 @@ function FileInfo(props) {
   const [tags, setTags] = useState([]);
   const [tagsOnFile, setTagsOnFile] = useState([]);
   const [selectedTagID, setSelectedTagID] = useState("");
+  const { langCode } = useContext(langCodeContext);
 
   function refresh() {
     fetch(`/api/v1/get_file_info`, {
@@ -90,7 +92,9 @@ function FileInfo(props) {
 
   function deleteFile() {
     // show Warning
-    if (window.confirm("Are you sure you want to delete this file?")) {
+    if (
+      window.confirm(tr("Are you sure you want to delete this file?", langCode))
+    ) {
       fetch(`/api/v1/delete_file`, {
         method: "POST",
         headers: {
@@ -127,7 +131,7 @@ function FileInfo(props) {
         if (data.error) {
           alert(data.error);
         } else {
-          alert("Filename updated");
+          alert(tr("Filename updated", langCode));
           refresh();
         }
       });
@@ -163,42 +167,42 @@ function FileInfo(props) {
 
   return (
     <div className="page">
-      <h3>File Details</h3>
+      <h3>{Tr("File Details")}</h3>
       <div>
         <a href={downloadURL} download>
-          <button>Download</button>
+          <button>{Tr("Download")}</button>
         </a>
         <button
           onClick={() => {
             props.setPlayingFile(file);
           }}
         >
-          Play
+          {Tr("Play")}
         </button>
         <button
           onClick={() => {
             navigate(`/files/${params.id}/review`);
           }}
         >
-          Review
+          {Tr("Review")}
         </button>
         <button
           onClick={() => {
             navigate(`/files/${params.id}/share`);
           }}
         >
-          Share
+          {Tr("Share")}
         </button>
         <button
           onClick={() => {
             deleteFile();
           }}
         >
-          Delete
+          {Tr("Delete")}
         </button>
       </div>
       <div>
-        <label htmlFor="foldername">Folder Name:</label>
+        <label htmlFor="foldername">{Tr("Folder Name")}</label>
         <input
           type="text"
           id="foldername"
@@ -208,7 +212,7 @@ function FileInfo(props) {
           }}
           readOnly
         />
-        <label htmlFor="filename">File Name:</label>
+        <label htmlFor="filename">{Tr("Filename")}</label>
         <input
           type="text"
           id="filename"
@@ -220,15 +224,15 @@ function FileInfo(props) {
             });
           }}
         />
-        <label htmlFor="filesize">File Size:</label>
+        <label htmlFor="filesize">{Tr("File size")}</label>
         <input type="text" id="filesize" value={file.filesize} readOnly />
       </div>
       <div className="horizontal">
-        <button onClick={updateFilename}>Save</button>
-        <button onClick={resetFilename}>Reset</button>
+        <button onClick={updateFilename}>{Tr("Save")}</button>
+        <button onClick={resetFilename}>{Tr("Reset")}</button>
       </div>
       <div>
-        <label>Tags:</label>
+        <label>{Tr("Tags")}</label>
         <ul>
           {tagsOnFile.map((tag) => {
             return (
@@ -245,7 +249,7 @@ function FileInfo(props) {
                     removeTagOnFile(tag.id);
                   }}
                 >
-                  Remove
+                  {Tr("Remove")}
                 </button>
               </li>
             );
@@ -257,7 +261,7 @@ function FileInfo(props) {
               setSelectedTagID(e.target.value);
             }}
           >
-            <option value="">Select a tag</option>
+            <option value="">{tr("Select a tag", langCode)}</option>
             {tags.map((tag) => {
               return (
                 <option key={tag.id} value={tag.id}>
@@ -270,7 +274,7 @@ function FileInfo(props) {
             onClick={() => {
               // check empty
               if (selectedTagID === "") {
-                alert("Please select a tag");
+                alert(tr("Please select a tag", langCode));
                 return;
               }
               fetch(`/api/v1/put_tag_on_file`, {
@@ -293,7 +297,7 @@ function FileInfo(props) {
                 });
             }}
           >
-            Add Tag
+            {Tr("Add tag")}
           </button>
         </div>
       </div>
diff --git a/web/src/component/FilesInFolder.js b/web/src/component/FilesInFolder.js
index e539788..c1df6cc 100644
--- a/web/src/component/FilesInFolder.js
+++ b/web/src/component/FilesInFolder.js
@@ -3,6 +3,7 @@ import { useState, useEffect } from "react";
 import { useNavigate } from "react-router-dom";
 import { useQuery } from "./Common";
 import FilesTable from "./FilesTable";
+import { Tr } from "../translate";
 
 function FilesInFolder(props) {
   let params = useParams();
@@ -107,13 +108,15 @@ function FilesInFolder(props) {
 
   return (
     <div className="page">
-      <h3>Files in Folder</h3>
+      <h3>{Tr("Files in Folder")}</h3>
       <div className="search_toolbar">
-        <button onClick={lastPage}>Last page</button>
+        <button onClick={lastPage}>{Tr("Last page")}</button>
         <button disabled>
-          {isLoading ? "Loading..." : `${offset} - ${offset + files.length}`}
+          {isLoading
+            ? Tr("Loading...")
+            : `${offset} - ${offset + files.length}`}
         </button>
-        <button onClick={nextPage}>Next page</button>
+        <button onClick={nextPage}>{Tr("Next page")}</button>
       </div>
       <FilesTable setPlayingFile={props.setPlayingFile} files={files} />
       <div>
@@ -123,8 +126,8 @@ function FilesInFolder(props) {
           onChange={(e) => setNewFoldername(e.target.value)}
         />
         <div>
-          <button onClick={() => updateFoldername()}>Save</button>
-          <button onClick={() => resetFoldername()}>Reset</button>
+          <button onClick={() => updateFoldername()}>{Tr("Save")}</button>
+          <button onClick={() => resetFoldername()}>{Tr("Reset")}</button>
         </div>
       </div>
     </div>
diff --git a/web/src/component/FilesTable.js b/web/src/component/FilesTable.js
index 7215f54..99bbcea 100644
--- a/web/src/component/FilesTable.js
+++ b/web/src/component/FilesTable.js
@@ -1,4 +1,5 @@
 import FileEntry from "./FileEntry";
+import { Tr } from "../translate";
 
 function FilesTable(props) {
   if (props.files.length === 0) {
@@ -8,9 +9,9 @@ function FilesTable(props) {
     <table>
       <thead>
         <tr>
-          <th>Filename</th>
-          <th>Folder Name</th>
-          <th>Size</th>
+          <th>{Tr("Filename")}</th>
+          <th>{Tr("Folder Name")}</th>
+          <th>{Tr("Size")}</th>
         </tr>
       </thead>
       <tbody>
diff --git a/web/src/component/FoldersTable.js b/web/src/component/FoldersTable.js
index 11ce14e..a693712 100644
--- a/web/src/component/FoldersTable.js
+++ b/web/src/component/FoldersTable.js
@@ -1,4 +1,5 @@
 import { useNavigate } from "react-router";
+import { Tr } from "../translate";
 
 function FoldersTable(props) {
   let navigate = useNavigate();
@@ -9,8 +10,8 @@ function FoldersTable(props) {
     <table>
       <thead>
         <tr>
-          <th>Folder name</th>
-          <th>Action</th>
+          <th>{Tr("Folder name")}</th>
+          <th>{Tr("Action")}</th>
         </tr>
       </thead>
       <tbody>
@@ -23,7 +24,7 @@ function FoldersTable(props) {
               {folder.foldername}
             </td>
             <td onClick={() => navigate(`/folders/${folder.id}`)}>
-              <button>View</button>
+              <button>{Tr("View")}</button>
             </td>
           </tr>
         ))}
diff --git a/web/src/component/GetRandomFiles.js b/web/src/component/GetRandomFiles.js
index 17cb749..54488dd 100644
--- a/web/src/component/GetRandomFiles.js
+++ b/web/src/component/GetRandomFiles.js
@@ -1,7 +1,8 @@
-import { useEffect, useState } from "react";
+import { useContext, useEffect, useState } from "react";
 import { useNavigate } from "react-router-dom";
 import { useQuery } from "./Common";
 import FilesTable from "./FilesTable";
+import { Tr, tr, langCodeContext } from "../translate";
 
 function GetRandomFiles(props) {
   const [files, setFiles] = useState([]);
@@ -10,6 +11,7 @@ function GetRandomFiles(props) {
   const navigator = useNavigate();
   const query = useQuery();
   const selectedTag = query.get("t") || "";
+  const { langCode } = useContext(langCodeContext);
 
   function getRandomFiles() {
     setIsLoading(true);
@@ -84,7 +86,7 @@ function GetRandomFiles(props) {
     <div className="page">
       <div className="search_toolbar">
         <button className="refresh" onClick={() => refresh(setFiles)}>
-          {isLoading ? "Loading..." : "Refresh"}
+          {isLoading ? Tr("Loading...") : Tr("Refresh")}
         </button>
         <select
           className="tag_select"
@@ -93,7 +95,7 @@ function GetRandomFiles(props) {
           }}
           value={selectedTag}
         >
-          <option value="">All</option>
+          <option value="">{tr("All", langCode)}</option>
           {tags.map((tag) => (
             <option key={tag.id} value={tag.id}>
               {tag.name}
diff --git a/web/src/component/Login.js b/web/src/component/Login.js
index 5b891b7..1cfc48f 100644
--- a/web/src/component/Login.js
+++ b/web/src/component/Login.js
@@ -1,14 +1,16 @@
 import { useNavigate } from "react-router-dom";
-import { useState } from "react";
+import { useContext, useState } from "react";
+import { Tr, tr, langCodeContext } from "../translate";
 
 function Login(props) {
   let navigate = useNavigate();
   let [username, setUsername] = useState("");
   let [password, setPassword] = useState("");
+  const { langCode } = useContext(langCodeContext);
 
   function login() {
     if (!username || !password) {
-      alert("Please enter username and password");
+      alert(tr("Please enter username and password", langCode));
       return;
     }
     fetch("/api/v1/login", {
@@ -34,15 +36,15 @@ function Login(props) {
 
   return (
     <div className="page">
-      <h2>Login</h2>
-      <label htmlFor="username">Username</label>
+      <h2>{Tr("Login")}</h2>
+      <label htmlFor="username">{Tr("Username")}</label>
       <input
         type="text"
         id="username"
         value={username}
         onChange={(e) => setUsername(e.target.value)}
       />
-      <label htmlFor="password">Password</label>
+      <label htmlFor="password">{Tr("Password")}</label>
       <input
         type="password"
         id="password"
@@ -56,13 +58,13 @@ function Login(props) {
         }}
       />
       <span>
-        <button onClick={login}>Login</button>
+        <button onClick={login}>{Tr("Login")}</button>
         <button
           onClick={() => {
             navigate("/manage/register");
           }}
         >
-          Register
+          {Tr("Register")}
         </button>
       </span>
     </div>
diff --git a/web/src/component/Manage.js b/web/src/component/Manage.js
index 8241cae..6aea074 100644
--- a/web/src/component/Manage.js
+++ b/web/src/component/Manage.js
@@ -1,13 +1,32 @@
 import { useNavigate } from "react-router";
 import Database from "./Database";
 
+import { Tr, langCodeContext, LANG_OPTIONS } from "../translate";
+import { useContext } from "react";
+
 function Manage(props) {
   let navigate = useNavigate();
+  const { langCode, setLangCode } = useContext(langCodeContext);
+  const codes = Object.keys(LANG_OPTIONS);
 
   return (
     <div className="page">
-      <h2>Manage</h2>
-      <p>Hi, {props.user.username}</p>
+      <h2>{Tr("Manage")}</h2>
+      <p>
+        {Tr("Hi")}, {props.user.username}
+      </p>
+
+      <select
+        onChange={(event) => {
+          setLangCode(codes[event.target.selectedIndex]);
+        }}
+      >
+        {codes.map((code) => {
+          const langOption = LANG_OPTIONS[code];
+          return <option key={code}>{langOption.name}</option>;
+        })}
+      </select>
+
       {props.user.role === 0 && (
         <div>
           <button
@@ -15,14 +34,14 @@ function Manage(props) {
               navigate("/manage/login");
             }}
           >
-            Login
+            {Tr("Login")}
           </button>
           <button
             onClick={() => {
               navigate("/manage/register");
             }}
           >
-            Register
+            {Tr("Register")}
           </button>
         </div>
       )}
@@ -33,7 +52,7 @@ function Manage(props) {
               navigate(`/manage/users/${props.user.id}`);
             }}
           >
-            Profile
+            {Tr("Profile")}
           </button>
           <button
             onClick={() => {
@@ -48,15 +67,17 @@ function Manage(props) {
                 });
             }}
           >
-            Logout
+            {Tr("Logout")}
           </button>
         </div>
       )}
       <hr />
       <div className="horizontal">
-        <button onClick={() => navigate("/manage/tags")}>Tags</button>
-        <button onClick={() => navigate("/manage/users")}>Users</button>
-        <button onClick={() => navigate("/manage/feedbacks")}>Feedbacks</button>
+        <button onClick={() => navigate("/manage/tags")}>{Tr("Tags")}</button>
+        <button onClick={() => navigate("/manage/users")}>{Tr("Users")}</button>
+        <button onClick={() => navigate("/manage/feedbacks")}>
+          {Tr("Feedbacks")}
+        </button>
       </div>
       <Database />
     </div>
diff --git a/web/src/component/ManageUser.js b/web/src/component/ManageUser.js
index 5cc7ff3..30292f7 100644
--- a/web/src/component/ManageUser.js
+++ b/web/src/component/ManageUser.js
@@ -1,12 +1,13 @@
 import { useState, useEffect } from "react";
 import { Link } from "react-router-dom";
+import { Tr } from "../translate";
 
 function ManageUser() {
   const [users, setUsers] = useState([]);
   const roleDict = {
     0: "Anonymous",
     1: "Admin",
-    2: "Normal User",
+    2: "User",
   };
 
   function getUsers() {
@@ -27,13 +28,13 @@ function ManageUser() {
 
   return (
     <div className="page">
-      <h3>Manage User</h3>
+      <h3>{Tr("Manage User")}</h3>
       <table>
         <thead>
           <tr>
-            <th>Name</th>
-            <th>Role</th>
-            <th>Active</th>
+            <th>{Tr("Name")}</th>
+            <th>{Tr("Role")}</th>
+            <th>{Tr("Active")}</th>
           </tr>
         </thead>
         <tbody>
@@ -42,7 +43,7 @@ function ManageUser() {
               <td>
                 <Link to={`/manage/users/${user.id}`}>@{user.username}</Link>
               </td>
-              <td>{roleDict[user.role]}</td>
+              <td>{Tr(roleDict[user.role])}</td>
               <td>
                 <input
                   type="checkbox"
@@ -57,13 +58,15 @@ function ManageUser() {
                         id: user.id,
                         active: e.target.checked,
                       }),
-                    }).then((res) => res.json()).then((data) => {
-                      if (data.error) {
-                        alert(data.error);
-                      } else {
-                        getUsers();
-                      }
-                    });
+                    })
+                      .then((res) => res.json())
+                      .then((data) => {
+                        if (data.error) {
+                          alert(data.error);
+                        } else {
+                          getUsers();
+                        }
+                      });
                   }}
                 />
               </td>
diff --git a/web/src/component/Register.js b/web/src/component/Register.js
index 5e975d5..7f98c15 100644
--- a/web/src/component/Register.js
+++ b/web/src/component/Register.js
@@ -1,5 +1,6 @@
 import { useNavigate } from "react-router-dom";
-import { useState } from "react";
+import { useContext, useState } from "react";
+import { tr, Tr, langCodeContext } from "../translate";
 
 function Register() {
   let navigate = useNavigate();
@@ -7,12 +8,13 @@ function Register() {
   const [password, setPassword] = useState("");
   const [password2, setPassword2] = useState("");
   const [role, setRole] = useState("");
+  const { langCode } = useContext(langCodeContext);
 
   function register() {
     if (!username || !password || !password2 || !role) {
-      alert("Please fill out all fields");
+      alert(tr("Please fill out all fields", langCode));
     } else if (password !== password2) {
-      alert("Passwords do not match");
+      alert(tr("Password do not match", langCode));
     } else {
       fetch("/api/v1/register", {
         method: "POST",
@@ -38,22 +40,22 @@ function Register() {
 
   return (
     <div className="page">
-      <h2>Register</h2>
-      <label htmlFor="username">Username</label>
+      <h2>{Tr("Register")}</h2>
+      <label htmlFor="username">{Tr("Username")}</label>
       <input
         type="text"
         id="username"
         value={username}
         onChange={(e) => setUsername(e.target.value)}
       />
-      <label htmlFor="password">Password</label>
+      <label htmlFor="password">{Tr("Password")}</label>
       <input
         type="password"
         id="password"
         value={password}
         onChange={(e) => setPassword(e.target.value)}
       />
-      <label htmlFor="password2">Confirm Password</label>
+      <label htmlFor="password2">{Tr("Confirm Password")}</label>
       <input
         type="password"
         id="password2"
@@ -66,13 +68,13 @@ function Register() {
           }
         }}
       />
-      <label htmlFor="role">Role</label>
+      <label htmlFor="role">{Tr("Role")}</label>
       <select value={role} onChange={(e) => setRole(e.target.value)}>
-        <option value="">Select a role</option>
-        <option value="2">User</option>
-        <option value="1">Admin</option>
+        <option value="">{tr("Select a role", langCode)}</option>
+        <option value="2">{tr("User", langCode)}</option>
+        <option value="1">{tr("Admin", langCode)}</option>
       </select>
-      <button onClick={register}>Register</button>
+      <button onClick={register}>{Tr("Register")}</button>
     </div>
   );
 }
diff --git a/web/src/component/ReviewEntry.js b/web/src/component/ReviewEntry.js
index 1541502..16174a3 100644
--- a/web/src/component/ReviewEntry.js
+++ b/web/src/component/ReviewEntry.js
@@ -1,25 +1,28 @@
 import { Link } from "react-router-dom";
 import { convertIntToDateTime } from "./Common";
+import { Tr, tr, langCodeContext } from "../translate";
+import { useContext } from "react";
 
 function ReviewEntry(props) {
+  const { langCode } = useContext(langCodeContext);
   return (
     <div>
       <h4>
         <Link to={`/manage/users/${props.review.user.id}`}>
           @{props.review.user.username}
         </Link>{" "}
-        review{" "}
+        {Tr("review")}{" "}
         <Link to={`/files/${props.review.file.id}`}>
           {props.review.file.filename}
         </Link>{" "}
-        on {convertIntToDateTime(props.review.created_at)}{" "}
+        {Tr("on")} {convertIntToDateTime(props.review.created_at)}{" "}
         {props.review.updated_at !== 0 &&
-          "(modified on " +
-            convertIntToDateTime(props.review.updated_at) +
-            ")"}{" "}
+          `(${tr("modified on", langCode)} ${convertIntToDateTime(
+            props.review.updated_at
+          )} ) `}
         {(props.user.role === 1 || props.review.user.id === props.user.id) &&
           props.user.role !== 0 && (
-            <Link to={`/manage/reviews/${props.review.id}`}>Edit</Link>
+            <Link to={`/manage/reviews/${props.review.id}`}>{Tr("Edit")}</Link>
           )}
       </h4>
       <p>{props.review.content}</p>
diff --git a/web/src/component/ReviewPage.js b/web/src/component/ReviewPage.js
index fba6bf2..0fa52db 100644
--- a/web/src/component/ReviewPage.js
+++ b/web/src/component/ReviewPage.js
@@ -1,6 +1,7 @@
 import { useState, useEffect } from "react";
 import { useParams } from "react-router";
 import ReviewEntry from "./ReviewEntry";
+import { Tr } from "../translate";
 
 function ReviewPage(props) {
   let params = useParams();
@@ -55,7 +56,7 @@ function ReviewPage(props) {
 
   return (
     <div className="page">
-      <h3>Review Page</h3>
+      <h3>{Tr("Review Page")}</h3>
       <div>
         {reviews.map((review) => (
           <ReviewEntry key={review.id} review={review} user={props.user} />
@@ -66,7 +67,7 @@ function ReviewPage(props) {
           value={newReview}
           onChange={(e) => setNewReview(e.target.value)}
         />
-        <button onClick={() => submitReview()}>Submit</button>
+        <button onClick={() => submitReview()}>{Tr("Submit")}</button>
       </div>
     </div>
   );
diff --git a/web/src/component/SearchFiles.js b/web/src/component/SearchFiles.js
index bed774c..494d5ca 100644
--- a/web/src/component/SearchFiles.js
+++ b/web/src/component/SearchFiles.js
@@ -1,7 +1,8 @@
-import { useState, useEffect } from "react";
+import { useState, useEffect, useContext } from "react";
 import { useNavigate } from "react-router-dom";
 import { useQuery } from "./Common";
 import FilesTable from "./FilesTable";
+import { Tr, tr, langCodeContext } from "../translate";
 
 function SearchFiles(props) {
   const navigator = useNavigate();
@@ -12,6 +13,7 @@ function SearchFiles(props) {
   const offset = parseInt(query.get("o")) || 0;
   const [isLoading, setIsLoading] = useState(false);
   const limit = 10;
+  const { langCode } = useContext(langCodeContext);
 
   function searchFiles() {
     // check empty filename
@@ -57,7 +59,7 @@ function SearchFiles(props) {
 
   return (
     <div className="page">
-      <h3>Search Files</h3>
+      <h3>{Tr("Search Files")}</h3>
       <div className="search_toolbar">
         <input
           onChange={(event) => setFilenameInput(event.target.value)}
@@ -67,7 +69,7 @@ function SearchFiles(props) {
             }
           }}
           type="text"
-          placeholder="Enter filename"
+          placeholder={tr("Enter filename", langCode)}
           value={filenameInput}
         />
         <button
@@ -75,13 +77,13 @@ function SearchFiles(props) {
             navigator(`/files?q=${filenameInput}&o=0`);
           }}
         >
-          {isLoading ? "Loading..." : "Search"}
+          {isLoading ? Tr("Loading...") : Tr("Search")}
         </button>
-        <button onClick={lastPage}>Last page</button>
+        <button onClick={lastPage}>{Tr("Last page")}</button>
         <button disabled>
           {offset} - {offset + files.length}
         </button>
-        <button onClick={nextPage}>Next page</button>
+        <button onClick={nextPage}>{Tr("Next page")}</button>
       </div>
       <FilesTable setPlayingFile={props.setPlayingFile} files={files} />
     </div>
diff --git a/web/src/component/SearchFolders.js b/web/src/component/SearchFolders.js
index 2746a42..fb623f4 100644
--- a/web/src/component/SearchFolders.js
+++ b/web/src/component/SearchFolders.js
@@ -1,7 +1,8 @@
-import { useEffect, useState } from "react";
+import { useContext, useEffect, useState } from "react";
 import { useNavigate } from "react-router-dom";
 import { useQuery } from "./Common";
 import FoldersTable from "./FoldersTable";
+import { Tr, tr, langCodeContext } from "../translate";
 
 function SearchFolders() {
   const navigator = useNavigate();
@@ -12,6 +13,7 @@ function SearchFolders() {
   const offset = parseInt(query.get("o")) || 0;
   const [isLoading, setIsLoading] = useState(false);
   const limit = 10;
+  const { langCode } = useContext(langCodeContext);
 
   function searchFolder() {
     if (foldername === "") {
@@ -55,7 +57,7 @@ function SearchFolders() {
 
   return (
     <div className="page">
-      <h3>Search Folders</h3>
+      <h3>{Tr("Search Folders")}</h3>
       <div className="search_toolbar">
         <input
           onChange={(event) => setFoldernameInput(event.target.value)}
@@ -65,7 +67,7 @@ function SearchFolders() {
             }
           }}
           type="text"
-          placeholder="Enter folder name"
+          placeholder={tr("Enter folder name", langCode)}
           value={foldernameInput}
         />
         <button
@@ -73,13 +75,13 @@ function SearchFolders() {
             navigator(`/folders?q=${foldernameInput}&o=0`);
           }}
         >
-          {isLoading ? "Loading..." : "Search"}
+          {isLoading ? Tr("Loading...") : Tr("Search")}
         </button>
-        <button onClick={lastPage}>Last page</button>
+        <button onClick={lastPage}>{Tr("Last page")}</button>
         <button disabled>
           {offset} - {offset + limit}
         </button>
-        <button onClick={nextPage}>Next page</button>
+        <button onClick={nextPage}>{Tr("Next page")}</button>
       </div>
       <FoldersTable folders={folders} />
     </div>
diff --git a/web/src/component/Share.js b/web/src/component/Share.js
index c1915da..d5ce206 100644
--- a/web/src/component/Share.js
+++ b/web/src/component/Share.js
@@ -1,6 +1,7 @@
 import { useEffect, useState } from "react";
 import { useParams } from "react-router";
 import FilesTable from "./FilesTable";
+import { Tr } from "../translate";
 
 function Share(props) {
   let params = useParams();
@@ -23,13 +24,14 @@ function Share(props) {
   }, [params]);
   return (
     <div className="page">
-      <h3>Share with others!</h3>
+      <h3>{Tr("Share with others!")}</h3>
       <p>
-        👇 Click the filename below to enjoy music!
-        <br />
+        {Tr("Share link")}:{" "}
+        <a href={window.location.href}>{window.location.href}</a>
       </p>
       <p>
-        Share link: <a href={window.location.href}>{window.location.href}</a>
+        👇 {Tr("Click the filename below to enjoy music!")}
+        <br />
       </p>
       <FilesTable setPlayingFile={props.setPlayingFile} files={file} />
     </div>
diff --git a/web/src/component/Tags.js b/web/src/component/Tags.js
index 6caa573..5806998 100644
--- a/web/src/component/Tags.js
+++ b/web/src/component/Tags.js
@@ -1,5 +1,6 @@
 import { useEffect, useState } from "react";
 import { Link } from "react-router-dom";
+import { Tr } from "../translate";
 
 function Tags() {
   const [tags, setTags] = useState([]);
@@ -25,14 +26,14 @@ function Tags() {
 
   return (
     <div className="page">
-      <h3>Tags</h3>
+      <h3>{Tr("Tags")}</h3>
       <table>
         <thead>
           <tr>
-            <th>Name</th>
-            <th>Description</th>
-            <th>Created By</th>
-            <th>Actions</th>
+            <th>{Tr("Name")}</th>
+            <th>{Tr("Description")}</th>
+            <th>{Tr("Created by")}</th>
+            <th>{Tr("Action")}</th>
           </tr>
         </thead>
         <tbody>
@@ -46,25 +47,25 @@ function Tags() {
                 </Link>
               </td>
               <td>
-                <Link to={`/manage/tags/${tag.id}`}>Edit</Link>
+                <Link to={`/manage/tags/${tag.id}`}>{Tr("Edit")}</Link>
               </td>
             </tr>
           ))}
         </tbody>
       </table>
       {!showAddTag && (
-        <button onClick={() => setShowAddTag(true)}>Add Tag</button>
+        <button onClick={() => setShowAddTag(true)}>{Tr("Add tag")}</button>
       )}
       {showAddTag && (
         <div>
-          <label htmlFor="newTagName">New Tag Name</label>
+          <label htmlFor="newTagName">{Tr("New Tag Name")}</label>
           <input
             type="text"
             id="newTagName"
             value={newTagName}
             onChange={(e) => setNewTagName(e.target.value)}
           />
-          <label htmlFor="newTagDescription">New Tag Description</label>
+          <label htmlFor="newTagDescription">{Tr("New Tag Description")}</label>
           <textarea
             id="newTagDescription"
             value={newTagDescription}
@@ -94,7 +95,7 @@ function Tags() {
                 });
             }}
           >
-            Create Tag
+        {Tr("Create tag")}
           </button>
         </div>
       )}
diff --git a/web/src/component/UserProfile.js b/web/src/component/UserProfile.js
index 926d095..3eb66ae 100644
--- a/web/src/component/UserProfile.js
+++ b/web/src/component/UserProfile.js
@@ -1,6 +1,7 @@
-import { useState, useEffect } from "react";
+import { useState, useEffect, useContext } from "react";
 import { useParams } from "react-router";
 import ReviewEntry from "./ReviewEntry";
+import { Tr, tr, langCodeContext } from "../translate";
 
 function UserProfile(props) {
   let params = useParams();
@@ -15,6 +16,7 @@ function UserProfile(props) {
     active: false,
     avatar_id: 0,
   });
+  const { langCode } = useContext(langCodeContext);
 
   function getReviews() {
     fetch("/api/v1/get_reviews_by_user", {
@@ -63,7 +65,7 @@ function UserProfile(props) {
 
   return (
     <div className="page">
-      <h3>User Profile</h3>
+      <h3>{Tr("User Profile")}</h3>
       <div className="horizontal">
         <input
           type="text"
@@ -103,26 +105,26 @@ function UserProfile(props) {
           }}
           disabled={props.user.id !== user.id && props.user.role !== 1}
         >
-          Save Username
+          {Tr("Save username")}
         </button>
       </div>
       <div>
         <input
           type="password"
           value={oldPassword}
-          placeholder="Old Password"
+          placeholder={tr("Old password", langCode)}
           onChange={(e) => setOldPassword(e.target.value)}
         />
         <input
           type="password"
           value={newPassword}
-          placeholder="New Password"
+          placeholder={tr("New password", langCode)}
           onChange={(e) => setNewPassword(e.target.value)}
         />
         <input
           type="password"
           value={newPasswordConfirm}
-          placeholder="Confirm New Password"
+          placeholder={tr("Confirm new password", langCode)}
           onChange={(e) => setNewPasswordConfirm(e.target.value)}
         />
         <button
@@ -144,7 +146,7 @@ function UserProfile(props) {
                 if (data.error) {
                   alert(data.error);
                 } else {
-                  alert("Password updated successfully!");
+                  alert(tr("Password updated successfully!", langCode));
                 }
               });
           }}
@@ -154,10 +156,10 @@ function UserProfile(props) {
             newPassword.length === 0
           }
         >
-          Change Password
+          {Tr("Change password")}
         </button>
       </div>
-      <h4>Reviews</h4>
+      <h4>{Tr("Reviews")}</h4>
       {reviews.map((review) => (
         <ReviewEntry key={review.id} review={review} user={props.user} />
       ))}
diff --git a/web/src/translate/index.js b/web/src/translate/index.js
new file mode 100644
index 0000000..7590b3b
--- /dev/null
+++ b/web/src/translate/index.js
@@ -0,0 +1,44 @@
+import { createContext, renderToString } from "react";
+import MAP_zh_CN from "./zh_CN";
+
+const LANG_OPTIONS = {
+  "en-US": {
+    name: "English",
+    langMap: {},
+    matches: ["en-US", "en"],
+  },
+  "zh-CN": {
+    name: "中文（简体）",
+    langMap: MAP_zh_CN,
+    matches: ["zh-CN", "zh"],
+  },
+};
+
+const langCodeContext = createContext("en-US");
+
+function tr(text, langCode) {
+  const option = LANG_OPTIONS[langCode];
+  if (option === undefined) {
+    return text;
+  }
+  const langMap = LANG_OPTIONS[langCode].langMap;
+
+  const translatedText = langMap[text.toLowerCase()];
+  if (translatedText === undefined) {
+    return text;
+  }
+
+  return translatedText;
+}
+
+function Tr(text) {
+  return (
+    <langCodeContext.Consumer>
+      {({ langCode }) => {
+        return tr(text, langCode);
+      }}
+    </langCodeContext.Consumer>
+  );
+}
+
+export { tr, Tr, LANG_OPTIONS, langCodeContext };
diff --git a/web/src/translate/zh_CN.js b/web/src/translate/zh_CN.js
new file mode 100644
index 0000000..38142b4
--- /dev/null
+++ b/web/src/translate/zh_CN.js
@@ -0,0 +1,105 @@
+const LANG_zh_CN = {
+  "feeling luckly": "随机",
+  files: "文件",
+  folders: "文件夹",
+  manage: "管理",
+  "manage user": "用户管理",
+  active: "激活",
+  "search files": "搜索文件",
+  "search folders": "搜索文件夹",
+  "enter filename": "输入文件名",
+  "enter folder name": "输入文件名",
+  search: "搜索",
+  "last page": "上一页",
+  all: "全部",
+  "loading...": "加载中...",
+  "next page": "下一页",
+  "search polders": "搜索文件夹",
+  "share with others!": "分享给好友！",
+  "click the filename below to enjoy music!": "点击下面的文件名开始享受音乐！",
+  "share link": "分享链接",
+  hi: "您好",
+  profile: "个人信息",
+  "user profile": "用户信息",
+  "save username": "更改用户名",
+  save: "保存",
+  reset: "重置",
+  "old password": "旧密码",
+  "new password": "新密码",
+  "confirm new password": "确认新密码",
+  "change password": "更改密码",
+  reviews: "评论",
+  review: "评论",
+  on: "在",
+  edit: "编辑",
+  "modified on": "修改于",
+  share: "分享",
+  delete: "删除",
+  remove: "移除",
+  "file details": "文件详情",
+  download: "下载",
+  logout: "登出",
+  tags: "标签",
+  "add tag": "添加标签",
+  "select a tag": "选择一个标签",
+  "review page": "评论页面",
+  submit: "提交",
+  users: "用户",
+  feedbacks: "反馈",
+  feedback: "反馈",
+  date: "时间",
+  action: "操作",
+  "new tag name": "新标签名",
+  "new tag description": "新标签描述",
+  "update database": "更新索引",
+  "updating...": "更新中...",
+  refresh: "刷新",
+  filename: "文件名",
+  "folder name": "文件夹名",
+  size: "大小",
+  "player status": "播放状态",
+  play: "播放",
+  stop: "停止",
+  "stop timer": "定时停止",
+  loop: "循环",
+  raw: "无损",
+  prepare: "预转码",
+  "file size": "文件大小",
+  login: "登陆",
+  register: "注册",
+  "play: play using browser player.": "播放: 使用浏览器播放",
+  "info for more actions.": "详细: 查看更多相关信息",
+  info: "详细",
+  close: "关闭",
+  "please enter username and password": "请输入用户名和密码",
+  username: "用户名",
+  password: "密码",
+  "please fill out all fields": "请完整填写所有信息",
+  "password do not match": "两次密码不一致",
+  "password updated successfully!": "密码已成功更新！",
+  role: "身份",
+  user: "用户",
+  admin: "管理员",
+  anonymous: "匿名",
+  "select a role": "选择身份",
+  "walk path": "遍历目录",
+  "pattern wav flac mp3": "拓展名 wav flac mp3",
+  "review updated": "已修改评论",
+  "review deleted": "已删除评论",
+  "edit review": "编辑评论",
+  view: "查看",
+  "tag updated successfully": "标签修改成功",
+  "tag deleted successfully": "标签删除成功",
+  "edit tag": "编辑标签",
+  id: "编号",
+  "created by": "创建者",
+  "create tag": "创建新标签",
+  name: "名称",
+  description: "描述",
+  "are you sure you want to delete this file?": "你确定要删除这个文件吗？",
+  "filename updated": "已修改文件名",
+  "please select a tag": "请选择一个标签",
+  "files in folder": "文件夹内",
+};
+
+export default LANG_zh_CN;