Added TypeScript for frontend

Added type definitions for components, functions, data
Added guards for network responses
fixes #8

front/src/assets/category.ts

@@ -1,4 +1,12 @@
-const categoryGraphics = new Map([
+import { isLiteralUnion } from "../utils/types"
+
+const categories = ["PORRIDGE", "conspects", "milk", "bred", "wathing", "cloth",
+"fruits_vegatables", "soup", "dinner", "conserves", "pens", "other_things"] as const
+type Category = typeof categories[number]
+
+const isCategory = (obj: unknown): obj is Category => isLiteralUnion(obj, categories) 
+
+const categoryGraphics = new Map<Category, string>([
     ["PORRIDGE", "static/PORRIDGE.jpg"],
     ["conspects", "static/conspects.jpg"],
     ["milk", "static/milk.jpg"],
@@ -14,7 +22,7 @@ const categoryGraphics = new Map([
 
 ])
 
-const categoryNames = new Map([
+const categoryNames = new Map<Category, string>([
     ["PORRIDGE", "PORRIDGE"],
     ["conspects", "Конспекты"],
     ["milk", "Молочные продукты"],
@@ -29,4 +37,5 @@ const categoryNames = new Map([
     ["other_things", "Всякая всячина"]
 ])
 
-export { categoryNames, categoryGraphics }
+export type { Category }
+export { categoryNames, categoryGraphics, isCategory }

front/src/assets/metro.ts

@@ -1,4 +1,7 @@
-const stations = {
+const lines = ['red', 'blue', 'green', 'orange', 'violet'] as const
+type Lines = typeof lines[number]
+
+const stations: Record<Lines, Set<string>> = {
     red: new Set([
         "Девяткино",
         "Гражданский проспект",
@@ -82,7 +85,7 @@ const stations = {
     ]),
 }
 
-const colors = {
+const colors: Record<Lines, string> = {
     red: "#D6083B",
     blue: "#0078C9",
     green: "#009A49",
@@ -90,7 +93,7 @@ const colors = {
     violet: "#702785",
 }
 
-const lines = {
+const lineNames: Record<Lines, string> = {
     red: "Красная",
     blue: "Синяя",
     green: "Зелёная",
@@ -98,4 +101,5 @@ const lines = {
     violet: "Фиолетовая",
 }
 
-export { stations, colors, lines }
+export type { Lines }
+export { lines, stations, colors, lineNames }