1 files changed, 93 insertions, 0 deletions
diff --git a/src/lib/hooks/useIntentHandler.ts b/src/lib/hooks/useIntentHandler.ts
new file mode 100644
index 000000000..8741530b5
--- /dev/null
+++ b/src/lib/hooks/useIntentHandler.ts
@@ -0,0 +1,93 @@
+import React from 'react'
+import * as Linking from 'expo-linking'
+import {isNative} from 'platform/detection'
+import {useComposerControls} from 'state/shell'
+import {useSession} from 'state/session'
+import {useCloseAllActiveElements} from 'state/util'
+
+type IntentType = 'compose'
+
+const VALID_IMAGE_REGEX = /^[\w.:\-_/]+\|\d+(\.\d+)?\|\d+(\.\d+)?$/
+
+export function useIntentHandler() {
+  const incomingUrl = Linking.useURL()
+  const composeIntent = useComposeIntent()
+
+  React.useEffect(() => {
+    const handleIncomingURL = (url: string) => {
+      // We want to be able to support bluesky:// deeplinks. It's unnatural for someone to use a deeplink with three
+      // slashes, like bluesky:///intent/follow. However, supporting just two slashes causes us to have to take care
+      // of two cases when parsing the url. If we ensure there is a third slash, we can always ensure the first
+      // path parameter is in pathname rather than in hostname.
+      if (url.startsWith('bluesky://') && !url.startsWith('bluesky:///')) {
+        url = url.replace('bluesky://', 'bluesky:///')
+      }
+
+      const urlp = new URL(url)
+      const [_, intent, intentType] = urlp.pathname.split('/')
+
+      // On native, our links look like bluesky://intent/SomeIntent, so we have to check the hostname for the
+      // intent check. On web, we have to check the first part of the path since we have an actual hostname
+      const isIntent = intent === 'intent'
+      const params = urlp.searchParams
+
+      if (!isIntent) return
+
+      switch (intentType as IntentType) {
+        case 'compose': {
+          composeIntent({
+            text: params.get('text'),
+            imageUrisStr: params.get('imageUris'),
+          })
+        }
+      }
+    }
+
+    if (incomingUrl) handleIncomingURL(incomingUrl)
+  }, [incomingUrl, composeIntent])
+}
+
+function useComposeIntent() {
+  const closeAllActiveElements = useCloseAllActiveElements()
+  const {openComposer} = useComposerControls()
+  const {hasSession} = useSession()
+
+  return React.useCallback(
+    ({
+      text,
+      imageUrisStr,
+    }: {
+      text: string | null
+      imageUrisStr: string | null // unused for right now, will be used later with intents
+    }) => {
+      if (!hasSession) return
+
+      closeAllActiveElements()
+
+      const imageUris = imageUrisStr
+        ?.split(',')
+        .filter(part => {
+          // For some security, we're going to filter out any image uri that is external. We don't want someone to
+          // be able to provide some link like "bluesky://intent/compose?imageUris=https://IHaveYourIpNow.com/image.jpeg
+          // and we load that image
+          if (part.includes('https://') || part.includes('http://')) {
+            return false
+          }
+          // We also should just filter out cases that don't have all the info we need
+          return VALID_IMAGE_REGEX.test(part)
+        })
+        .map(part => {
+          const [uri, width, height] = part.split('|')
+          return {uri, width: Number(width), height: Number(height)}
+        })
+
+      setTimeout(() => {
+        openComposer({
+          text: text ?? undefined,
+          imageUris: isNative ? imageUris : undefined,
+        })
+      }, 500)
+    },
+    [hasSession, closeAllActiveElements, openComposer],
+  )
+}