Improve unsplash mode

bot.py

@@ -69,7 +69,19 @@ def post_img_local(mastodon, text, log, config):
     return media_dict;
 
 def post_unsplash_random_image(mastodon, log, config):
-    response    = requests.get('https://api.unsplash.com/photos/random?client_id=03ad5bfbaa0acd6c96a728d425e533683ec25e5fb7fcf99f6461720b3d0d75a1')
+    collection_url = get_parameter("collection_url", config)
+    unsplash_client_id  = get_parameter("unsplash_client_id", config)
+    collecion_file = open(collection_filepath,'r')
+    collections    = json.loads(collecion_file.read())
+    collecion_file.close()
+
+    count_collection = len(collections)-1
+    if count_collection > -1:
+      id_collection    = randint(0,count_collection)
+      collection_url="&collections="+str(collections[id_collection])
+    else:
+      collection_url=''
+    response    = requests.get("https://api.unsplash.com/photos/random?client_id="+unsplash_client_id+collection_url)
     randim_json = json.loads(response.text)
     randim_url  = "{}&q=85&crop=entropy&cs=tinysrgb&w=2048&fit=max".format(randim_json['urls']['raw'])