feat/flask: total rework and finalization

- Finished all locale pages
- Updated styles, fixed some mobile problems
- Updated texts on index page
- Fixed flask locales search error, now it throws 404
- Something else, that I already forgot

app.py

@@ -1,9 +1,16 @@
-import os
+from os import path, listdir
 from datetime import date
 from configparser import ConfigParser
 
-from flask import Flask, render_template, url_for, redirect
-
+from flask import (
+    Flask,
+    abort,
+    redirect,
+    render_template,
+    request,
+    send_from_directory,
+    url_for,
+)
 
 cp = ConfigParser()
 app = Flask(__name__)
@@ -11,32 +18,65 @@ app = Flask(__name__)
 
 def load_all_locales():
     locales = {}
-    locales_dir = 'locales'
-    for filename in os.listdir(locales_dir):
-        if filename.endswith('.ini'):
-            lang = os.path.splitext(filename)[0]
+    locales_dir = "locales"
+
+    for filename in listdir(locales_dir):
+        if filename.endswith(".ini"):
+            lang = path.splitext(filename)[0]
             cp = ConfigParser()
-            with open(os.path.join(locales_dir, filename), encoding='utf-8') as f:
+            with open(path.join(locales_dir, filename), encoding="utf-8") as f:
                 cp.read_file(f)
             locales[lang] = {section: dict(cp[section]) for section in cp.sections()}
+    
     return locales
 
+
 locales = load_all_locales()
 
 
+@app.route("/favicon.ico")
+def favicon():
+    return send_from_directory(
+        app.static_folder,
+        "favicon.ico",
+        mimetype="image/vnd.microsoft.icon"
+    )
+
+
 @app.route("/")
 def home():
     return redirect(url_for("index", lang="en"))
 
+
 @app.route("/<lang>")
 def index(lang):
-    return render_template(f'{lang}.html', locale=locales[lang], lang=lang, year=date.today().year)  # TODO: Check for vulnerability
+
+    if lang not in locales:
+        abort(404)
+
+    return render_template(
+        f"{lang}.html",
+        locale=locales[lang],
+        lang=lang,
+        year=date.today().year,
+        current=request.endpoint,
+    )
+
 
 @app.route("/<lang>/download")
 def download_page(lang):
-    return render_template('tmpl/download.htm', locale=locales[lang], lang=lang, year=date.today().year)
+
+    if lang not in locales:
+        abort(404)
+
+    return render_template(
+        "tmpl/download.htm",
+        locale=locales[lang],
+        lang=lang,
+        year=date.today().year,
+        current=request.endpoint,
+    )
 
 
 if __name__ == "__main__":
-    
     app.run(host="0.0.0.0", debug=True)