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src/App.tsx

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+'use client'
+
+import { useEffect, useState } from 'react'
+import axios from 'axios'
+import { app } from '@tauri-apps/api'
+import { invoke } from '@tauri-apps/api/core'
+import { openUrl } from '@tauri-apps/plugin-opener'
+import { arch, platform } from '@tauri-apps/plugin-os'
+import {
+  BaseDirectory,
+  create,
+  exists,
+  readTextFile,
+  writeTextFile
+} from '@tauri-apps/plugin-fs'
+import './App.css'
+
+interface LauncherUpdate {
+    id: string
+    releaseDate: number
+    downloadUrl: string
+    sha512sum: string
+}
+
+export default function App () {
+  const [state, setState] = useState<string>('Loading...')
+
+  useEffect(() => {
+    ;(async () => {
+      setState('Checking for updates...')
+
+      let updaterLatestRequest
+      let launcherLatestRequest
+      let launcherUpdateData: LauncherUpdate | null
+
+      try {
+        updaterLatestRequest = await axios.get(
+          'https://games.lncvrt.xyz/api/launcher/loader/latest'
+        )
+        launcherLatestRequest = await axios.get(
+          'https://games.lncvrt.xyz/api/launcher/latest'
+        )
+      } catch {
+        setState('Failed. Check internet connection.')
+        return
+      }
+
+      if (
+        updaterLatestRequest.status !== 200 ||
+        launcherLatestRequest.status !== 200
+      ) {
+        setState('Failed. Try again later.')
+        return
+      }
+
+      const version = await app.getVersion()
+      if (version !== updaterLatestRequest.data) {
+        setState('Loader update required')
+        return
+      }
+
+      const options = {
+        baseDir: BaseDirectory.AppLocalData
+      }
+
+      let latest = false
+      if (await exists('.version', options))
+        latest =
+          (await readTextFile('.version', options)) ==
+          launcherLatestRequest.data
+
+      if (!latest) {
+        setState('Downloading new update...')
+        try {
+          const launcherUpdateRequest = await axios.get(
+            `https://games.lncvrt.xyz/api/launcher/loader/update-data?platform=${platform()}&arch=${arch()}`
+          )
+          launcherUpdateData = launcherUpdateRequest.data
+        } catch {
+          setState('Failed. Check internet connection.')
+          return
+        }
+        if (!launcherUpdateData) {
+          setState('Failed. Check internet connection.')
+          return
+        }
+        const downloadResult = await invoke('download', {
+          url: launcherUpdateData.downloadUrl,
+          hash: launcherUpdateData.sha512sum
+        })
+        if (downloadResult == '-1') {
+          setState('Failed. Check internet connection.')
+          return
+        } else if (downloadResult == '-2') {
+          setState('File integrity check failed.')
+          return
+        } else if (downloadResult == '-3') {
+          setState('Failed to unzip update.')
+          return
+        }
+        if (await exists('.version', options)) await create('.version', options)
+        await writeTextFile('.version', launcherLatestRequest.data, options)
+      }
+
+      setState('Starting...')
+      invoke('load')
+    })()
+  }, [])
+
+  return (
+    <>
+      <div className='absolute left-1/2 top-[20%] -translate-x-1/2 flex flex-col items-center'>
+        <img src='/Icon.png' width={128} height={128} alt='' draggable={false} />
+        <div
+          className={`${
+            state !== 'Loader update required' ? 'mt-10' : 'mt-4'
+          } text-center`}
+        >
+          <p className='whitespace-nowrap'>{state}</p>
+          <button
+            hidden={state !== 'Loader update required'}
+            className='mt-4'
+            onClick={async () =>
+              await openUrl('https://games.lncvrt.xyz/download')
+            }
+          >
+            Update
+          </button>
+        </div>
+      </div>
+    </>
+  )
+}