feat: allow running elk with a single server (#1606)

composables/sign-in.ts

@@ -0,0 +1,77 @@
+import type { Ref } from 'vue'
+
+export const useSignIn = (input?: Ref<HTMLInputElement | undefined>) => {
+  const singleInstanceServer = useAppConfig().singleInstanceServer
+  const userSettings = useUserSettings()
+  const users = useUsers()
+  const { t } = useI18n()
+
+  const busy = ref(false)
+  const error = ref(false)
+  const server = ref('')
+  const displayError = ref(false)
+
+  async function oauth() {
+    if (busy.value)
+      return
+
+    busy.value = true
+    error.value = false
+    displayError.value = false
+
+    await nextTick()
+
+    if (!singleInstanceServer && server.value)
+      server.value = server.value.split('/')[0]
+
+    try {
+      let href: string
+      if (singleInstanceServer) {
+        href = await (globalThis.$fetch as any)(`/api/${publicServer.value}/login`, {
+          method: 'POST',
+          body: {
+            force_login: users.value.length > 0,
+            origin: location.origin,
+            lang: userSettings.value.language,
+          },
+        })
+        busy.value = false
+      }
+      else {
+        href = await (globalThis.$fetch as any)(`/api/${server.value || publicServer.value}/login`, {
+          method: 'POST',
+          body: {
+            force_login: users.value.some(u => u.server === server.value),
+            origin: location.origin,
+            lang: userSettings.value.language,
+          },
+        })
+      }
+      location.href = href
+    }
+    catch (err) {
+      if (singleInstanceServer) {
+        console.error(err)
+        busy.value = false
+        await openErrorDialog({
+          title: t('common.error'),
+          messages: [t('error.sign_in_error')],
+          close: t('action.close'),
+        })
+      }
+      else {
+        displayError.value = true
+        error.value = true
+        await nextTick()
+        input?.value?.focus()
+        await nextTick()
+        setTimeout(() => {
+          busy.value = false
+          error.value = false
+        }, 512)
+      }
+    }
+  }
+
+  return { busy, displayError, error, server, singleInstanceServer, oauth }
+}