--- a/libervia/pages/photos/album/_browser/__init__.py	Sat Sep 05 21:59:23 2020 +0200
+++ b/libervia/pages/photos/album/_browser/__init__.py	Sat Sep 05 21:59:38 2020 +0200
@@ -1,11 +1,15 @@
-from browser import document, window, bind, html, DOMNode
+from browser import document, window, bind, html, DOMNode, aio
 from javascript import JSON
 from bridge import Bridge
+from aio_bridge import Bridge as AIOBridge
 from template import Template
 import dialog
 from slideshow import SlideShow
 from invitation import InvitationManager
 import alt_media_player
+# we use tmp_aio because `blob` is not handled in Brython's aio
+import tmp_aio
+
 
 cache_path = window.cache_path
 files_service = window.files_service
@@ -15,6 +19,7 @@
 except AttributeError:
     pass
 bridge = Bridge()
+aio_bridge = AIOBridge()
 
 alt_media_player.install_if_needed()
 
@@ -167,6 +172,72 @@
         cancel_cb=lambda evt, notif_elt: delete_cancel(evt, notif_elt, item_elt, item),
     )
 
+# cover
+
+async def cover_ok(evt, notif_elt, item_elt, item):
+    # we first need to get a blob of the image
+    img_elt = item_elt.select_one("img")
+    # the simplest way is to download it
+    r = await tmp_aio.ajax("GET", img_elt.src, "blob")
+    if r.status != 200:
+        dialog.notification.show(
+            f"can't retrieve cover: {r.status}: {r.statusText}",
+            level="error"
+        )
+        return
+    img_blob = r.response
+    # now we'll upload it via HTTP Upload, we need a slow
+    img_name = img_elt.src.rsplit('/', 1)[-1]
+    img_size = img_blob.size
+
+    slot = await aio_bridge.fileHTTPUploadGetSlot(
+        img_name,
+        img_size,
+        '',
+        files_service
+    )
+    get_url, put_url, headers = slot
+    # we have the slot, we can upload image
+    r = await tmp_aio.ajax("PUT", put_url, "", img_blob)
+    if r.status != 201:
+        dialog.notification.show(
+            f"can't upload cover: {r.status}: {r.statusText}",
+            level="error"
+        )
+        return
+    extra = {"thumb_url": get_url}
+    album_name = files_path.rsplit('/', 1)[-1]
+    await aio_bridge.interestsRegisterFileSharing(
+        files_service,
+        "photos",
+        "",
+        files_path,
+        album_name,
+        JSON.stringify(extra),
+    )
+    dialog.notification.show("Album cover has been changed")
+
+
+def cover_cancel(evt, notif_elt, item_elt, item):
+    notif_elt.remove()
+    item_elt.classList.remove("selected_for_action")
+
+
+def on_cover(evt):
+    evt.stopPropagation()
+    target = evt.currentTarget
+    item_elt = DOMNode(target.elt.closest('.item'))
+    item_elt.classList.add("selected_for_action")
+    item = JSON.parse(item_elt.dataset.item)
+    dialog.Confirm(
+        f"use {item['name']!r} for this album cover?",
+        ok_label="use as cover",
+    ).show(
+        ok_cb=lambda evt, notif_elt: aio.run(cover_ok(evt, notif_elt, item_elt, item)),
+        cancel_cb=lambda evt, notif_elt: cover_cancel(evt, notif_elt, item_elt, item),
+    )
+
+
 # slideshow
 
 @bind(".photo_thumb_click", "click")
@@ -210,6 +281,8 @@
 
 for elt in document.select('.action_delete'):
     elt.bind("click", on_delete)
+for elt in document.select('.action_cover'):
+    elt.bind("click", on_cover)
 
 # manage