make sane_value validation a little more general

clients/urwid/main.py

@@ -1265,7 +1265,7 @@ class App(object):
         self.loop.stop()
         call("clear", shell=True)
         try:
-            name = nameloop(self.network, "Choose a new username", True)
+            name = nameloop(self.network, "Choose a new username")
             self.network.user_update(user_name=name)
             motherfucking_rainbows("~~hello there %s~~" % name)
             sleep(0.8)
@@ -1281,7 +1281,7 @@ class App(object):
         self.loop.stop()
         call("clear", shell=True)
         try:
-            password = password_loop("Choose a new password. Can be empty", True)
+            password = password_loop("Choose a new password. Can be empty")
             self.network.user_update(auth_hash=self.network._hash(password))
             motherfucking_rainbows("SET NEW PASSWORD")
             sleep(0.8)
@@ -2368,19 +2368,18 @@ def paren_prompt(text, positive=True, choices=[], function=input, default=None):
         return ""
 
 
-def sane_value(network, key, prompt, positive=True, allow_empty=False):
+def sane_value(prompt, validate, positive=True, function=input):
+    """Prompts for an input with paren_prompt until validate(response)
+    returns None (or something falsy). Otherwise the returned string is used
+    as the new prompt.
+    """
     while 1:
-        response = paren_prompt(prompt, positive)
+        response = paren_prompt(prompt, positive, function=function)
-        if allow_empty and response == "":
+        error = validate(response)
+        if not error:
             return response
-        try:
+        prompt = str(error) if error != None else ""
-            network.validate(key, response)
-        except AssertionError as e:
-            prompt = e.description
         positive = False
-        else:
-            return response
-
 
 def password_loop(prompt, positive=True):
     while 1:
@@ -2397,15 +2396,14 @@ def password_loop(prompt, positive=True):
             return response1
 
 
-def nameloop(network, prompt, positive):
+def nameloop(network, prompt, positive=True):
-    while 1:
+    def validate_name(name):
-        name = sane_value(network, "user_name", prompt, positive)
+        try: network.validate("user_name", name)
+        except AssertionError as e:
+            return e.description
         if network.user_is_registered(name):
-            prompt = "%s is already registered" % name
+            return "%s is already registered" % name
-            positive = False
+    return sane_value(prompt, validate_name, positive)
-        else:
-            return name
-
 
 def log_in(network, name="", password=""):
     """
@@ -2415,7 +2413,12 @@ def log_in(network, name="", password=""):
     curses app.
     """
     if not name:
-        name = sane_value(network, "user_name", "Username", allow_empty=True)
+        def validate_name(response):
+            if response != "": # allow empty username
+                try: network.validate("user_name", response)
+                except AssertionError as e:
+                    return e.description
+        name = sane_value("Username", validate_name)
     if name == "":
         motherfucking_rainbows("~~W3 4R3 4n0nYm0u5~~")
     else:
@@ -2430,14 +2433,12 @@ def log_in(network, name="", password=""):
             motherfucking_rainbows("~~welcome back {}~~".format(network.user_name))
 
         except ConnectionRefusedError:
-            def login_loop(prompt, positive):
+            def validate_creds(password):
                 try:
-                    password = paren_prompt(prompt, positive, function=getpass)
                     network.set_credentials(name, password)
                 except ConnectionRefusedError:
-                    login_loop("// R E J E C T E D //.", False)
+                    return "// R E J E C T E D //."
-
+            password = sane_value("Enter your password", validate_creds, function=getpass)
-            login_loop("Enter your password", True)
             motherfucking_rainbows("~~welcome back {}~~".format(network.user_name))
 
         except ValueError:
@@ -2448,7 +2449,7 @@ def log_in(network, name="", password=""):
             )
 
             if response == "c":
-                name = nameloop(network, "Pick a new name", True)
+                name = nameloop(network, "Pick a new name")
 
             elif response == "n":
                 raise InterruptedError