init: MVP

codeforces/client/spinner.py

@@ -0,0 +1,47 @@
+from enum import Enum, auto
+import time
+import threading
+
+class Spinner:
+    class State(Enum):
+        LOADING = auto()
+        SUCCESS = '✓'
+        FAILURE = '⨯'
+
+    def __init__(self, text: str):
+        self.text = text
+        self.state = self.State.LOADING
+
+    def __enter__(self):
+        t = threading.Thread(target = self._thread_fn)
+        t.start()
+        self.thread = t
+        return self
+
+    def __exit__(self, *_):
+        if self.state == self.State.LOADING:
+            self.state = self.State.SUCCESS
+        if self.thread:
+            self.thread.join()
+
+    def fail(self):
+        if self.thread:
+            self.state = self.State.FAILURE
+            self.thread.join()
+            self.thread = None
+
+    def done(self):
+        if self.thread:
+            self.state = self.State.SUCCESS
+            self.thread.join()
+            self.thread = None
+
+    def _thread_fn(self):
+        interval = 80
+        spinner = ["⠋", "⠙", "⠹", "⠸", "⠼", "⠴", "⠦", "⠧", "⠇", "⠏"]
+        i = 0
+        while self.state == self.State.LOADING:
+            i = (i + 1) % len(spinner)
+            print(f"\r{spinner[i]} {self.text}", end=' ')
+            time.sleep(interval / 1000)
+        print(f"\r{self.state.value} {self.text}")