fix(submit): harden atcoder and codeforces submit flow

Problem: AtCoder file upload always used a `.cpp` temp file regardless
of language. CF submit used `solve_cloudflare=True` causing a spurious
"No Cloudflare challenge found" error, and `_wait_for_gate_reload` in
`login_action` was dead code. Stale or expired cookies caused silent
auth failures with no recovery. The `uv.spawn` ndjson path for submit
had no overall timeout, so a hung browser process would live forever.

Solution: Replace AtCoder's temp file with `page.set_input_files` using
an in-memory buffer and correct extension via `_LANGUAGE_ID_EXTENSION`.
Replace CF's temp-file/fallback dance with a direct
`textarea[name="source"]` fill and set `solve_cloudflare=False` on the
submit fetch. Add a fast-path that skips the homepage login check when
cookies exist, with automatic stale-cookie recovery via `_retried` flag
on redirect-to-login detection. Remove `_wait_for_gate_reload`. Fix
`_ensure_browser` to propagate install errors instead of swallowing
them. Add a 120s kill timer to the ndjson `uv.spawn` submit path.

lua/cp/scraper.lua

@@ -92,6 +92,10 @@ local function run_scraper(platform, subcommand, args, opts)
       env = spawn_env_list(env),
       cwd = plugin_path,
     }, function(code, signal)
+      if timer and not timer:is_closing() then
+        timer:stop()
+        timer:close()
+      end
       if buf ~= '' and opts.on_event then
         local ok_tail, ev_tail = pcall(vim.json.decode, buf)
         if ok_tail then
@@ -124,6 +128,31 @@ local function run_scraper(platform, subcommand, args, opts)
       return { success = false, error = 'spawn failed' }
     end
 
+    local timer = nil
+    if subcommand == 'submit' then
+      timer = uv.new_timer()
+      timer:start(120000, 0, function()
+        timer:stop()
+        timer:close()
+        if stdin_pipe and not stdin_pipe:is_closing() then
+          stdin_pipe:close()
+        end
+        if not stdout:is_closing() then
+          stdout:close()
+        end
+        if not stderr:is_closing() then
+          stderr:close()
+        end
+        if handle and not handle:is_closing() then
+          handle:kill(15)
+          handle:close()
+        end
+        if opts.on_exit then
+          opts.on_exit({ success = false, error = 'submit timed out' })
+        end
+      end)
+    end
+
     if stdin_pipe then
       uv.write(stdin_pipe, opts.stdin, function()
         uv.shutdown(stdin_pipe, function()

scrapers/atcoder.py

@@ -6,7 +6,6 @@ import os
 import re
 import subprocess
 import sys
-import tempfile
 import time
 from typing import Any
 
@@ -38,6 +37,11 @@ from .timeouts import (
     HTTP_TIMEOUT,
 )
 
+_LANGUAGE_ID_EXTENSION = {
+    "6017": "cc",
+    "6082": "py",
+}
+
 MIB_TO_MB = 1.048576
 BASE_URL = "https://atcoder.jp"
 ARCHIVE_URL = f"{BASE_URL}/contests/archive"
@@ -274,23 +278,20 @@ def _ensure_browser() -> None:
         from patchright._impl._driver import compute_driver_executable  # type: ignore[import-untyped,unresolved-import]
 
         node, cli = compute_driver_executable()
-        browser_info = subprocess.run(
-            [node, cli, "install", "--dry-run", "chromium"],
-            capture_output=True,
-            text=True,
-        )
-        for line in browser_info.stdout.splitlines():
-            if "Install location:" in line:
-                install_dir = line.split(":", 1)[1].strip()
-                if not os.path.isdir(install_dir):
-                    print(json.dumps({"status": "installing_browser"}), flush=True)
-                    subprocess.run(
-                        [node, cli, "install", "chromium"],
-                        check=True,
-                    )
-                break
     except Exception:
-        pass
+        return
+    browser_info = subprocess.run(
+        [node, cli, "install", "--dry-run", "chromium"],
+        capture_output=True,
+        text=True,
+    )
+    for line in browser_info.stdout.splitlines():
+        if "Install location:" in line:
+            install_dir = line.split(":", 1)[1].strip()
+            if not os.path.isdir(install_dir):
+                print(json.dumps({"status": "installing_browser"}), flush=True)
+                subprocess.run([node, cli, "install", "chromium"], check=True)
+            break
 
 
 def _submit_headless(
@@ -299,6 +300,7 @@ def _submit_headless(
     source_code: str,
     language_id: str,
     credentials: dict[str, str],
+    _retried: bool = False,
 ) -> "SubmitResult":
     from pathlib import Path
 
@@ -321,9 +323,10 @@ def _submit_headless(
         except Exception:
             pass
 
-    logged_in = False
+    logged_in = cookie_cache.exists() and not _retried
     login_error: str | None = None
     submit_error: str | None = None
+    needs_relogin = False
 
     def check_login(page):
         nonlocal logged_in
@@ -345,7 +348,10 @@ def _submit_headless(
             login_error = str(e)
 
     def submit_action(page):
-        nonlocal submit_error
+        nonlocal submit_error, needs_relogin
+        if "/login" in page.url:
+            needs_relogin = True
+            return
         try:
             _solve_turnstile(page)
             page.select_option(
@@ -356,16 +362,12 @@ def _submit_headless(
                 f'select[name="data.LanguageId"] option[value="{language_id}"]'
             ).wait_for(state="attached", timeout=BROWSER_ELEMENT_WAIT)
             page.select_option('select[name="data.LanguageId"]', language_id)
-            with tempfile.NamedTemporaryFile(
+            ext = _LANGUAGE_ID_EXTENSION.get(language_id, "txt")
-                mode="w", suffix=".cpp", delete=False, prefix="atcoder_"
+            page.set_input_files(
-            ) as tf:
+                "#input-open-file",
-                tf.write(source_code)
+                {"name": f"solution.{ext}", "mimeType": "text/plain", "buffer": source_code.encode()},
-                tmp_path = tf.name
+            )
-            try:
+            page.wait_for_timeout(BROWSER_SETTLE_DELAY)
-                page.set_input_files("#input-open-file", tmp_path)
-                page.wait_for_timeout(BROWSER_SETTLE_DELAY)
-            finally:
-                os.unlink(tmp_path)
             page.locator('button[type="submit"]').click()
             page.wait_for_url(
                 lambda url: "/submissions/me" in url, timeout=BROWSER_NAV_TIMEOUT
@@ -378,14 +380,11 @@ def _submit_headless(
             headless=True,
             timeout=BROWSER_SESSION_TIMEOUT,
             google_search=False,
-            cookies=saved_cookies,
+            cookies=saved_cookies if (cookie_cache.exists() and not _retried) else [],
         ) as session:
-            print(json.dumps({"status": "checking_login"}), flush=True)
+            if not (cookie_cache.exists() and not _retried):
-            session.fetch(
+                print(json.dumps({"status": "checking_login"}), flush=True)
-                f"{BASE_URL}/home",
+                session.fetch(f"{BASE_URL}/home", page_action=check_login, network_idle=True)
-                page_action=check_login,
-                network_idle=True,
-            )
 
             if not logged_in:
                 print(json.dumps({"status": "logging_in"}), flush=True)
@@ -395,9 +394,7 @@ def _submit_headless(
                     solve_cloudflare=True,
                 )
                 if login_error:
-                    return SubmitResult(
+                    return SubmitResult(success=False, error=f"Login failed: {login_error}")
-                        success=False, error=f"Login failed: {login_error}"
-                    )
 
             print(json.dumps({"status": "submitting"}), flush=True)
             session.fetch(
@@ -413,12 +410,16 @@ def _submit_headless(
             except Exception:
                 pass
 
-            if submit_error:
+        if needs_relogin and not _retried:
-                return SubmitResult(success=False, error=submit_error)
+            cookie_cache.unlink(missing_ok=True)
-
+            return _submit_headless(
-            return SubmitResult(
+                contest_id, problem_id, source_code, language_id, credentials, _retried=True
-                success=True, error="", submission_id="", verdict="submitted"
             )
+
+        if submit_error:
+            return SubmitResult(success=False, error=submit_error)
+
+        return SubmitResult(success=True, error="", submission_id="", verdict="submitted")
     except Exception as e:
         return SubmitResult(success=False, error=str(e))
 

scrapers/codeforces.py

@@ -2,9 +2,7 @@
 
 import asyncio
 import json
-import os
 import re
-import tempfile
 from typing import Any
 
 import requests
@@ -21,10 +19,8 @@ from .models import (
     TestCase,
 )
 from .timeouts import (
-    BROWSER_ELEMENT_WAIT,
     BROWSER_NAV_TIMEOUT,
     BROWSER_SESSION_TIMEOUT,
-    BROWSER_SETTLE_DELAY,
     HTTP_TIMEOUT,
 )
 
@@ -307,24 +303,13 @@ class CodeforcesScraper(BaseScraper):
         )
 
 
-def _wait_for_gate_reload(page, wait_selector: str) -> None:
-    from .atcoder import _solve_turnstile
-
-    if "Verification" not in page.title():
-        return
-    _solve_turnstile(page)
-    page.wait_for_function(
-        f"() => !!document.querySelector('{wait_selector}')",
-        timeout=BROWSER_ELEMENT_WAIT,
-    )
-
-
 def _submit_headless(
     contest_id: str,
     problem_id: str,
     source_code: str,
     language_id: str,
     credentials: dict[str, str],
+    _retried: bool = False,
 ) -> SubmitResult:
     from pathlib import Path
 
@@ -349,9 +334,10 @@ def _submit_headless(
         except Exception:
             pass
 
-    logged_in = False
+    logged_in = cookie_cache.exists() and not _retried
     login_error: str | None = None
     submit_error: str | None = None
+    needs_relogin = False
 
     def check_login(page):
         nonlocal logged_in
@@ -362,10 +348,6 @@ def _submit_headless(
 
     def login_action(page):
         nonlocal login_error
-        try:
-            _wait_for_gate_reload(page, "#enterForm")
-        except Exception:
-            pass
         try:
             page.fill(
                 'input[name="handleOrEmail"]',
@@ -383,28 +365,21 @@ def _submit_headless(
             login_error = str(e)
 
     def submit_action(page):
-        nonlocal submit_error
+        nonlocal submit_error, needs_relogin
+        if "/enter" in page.url or "/login" in page.url:
+            needs_relogin = True
+            return
         try:
             _solve_turnstile(page)
         except Exception:
             pass
-        tmp_path: str | None = None
         try:
             page.select_option(
                 'select[name="submittedProblemIndex"]',
                 problem_id.upper(),
             )
             page.select_option('select[name="programTypeId"]', language_id)
-            with tempfile.NamedTemporaryFile(
+            page.fill('textarea[name="source"]', source_code)
-                mode="w", suffix=".cpp", delete=False, prefix="cf_"
-            ) as tf:
-                tf.write(source_code)
-                tmp_path = tf.name
-            try:
-                page.set_input_files('input[name="sourceFile"]', tmp_path)
-                page.wait_for_timeout(BROWSER_SETTLE_DELAY)
-            except Exception:
-                page.fill('textarea[name="source"]', source_code)
             page.locator("form.submit-form input.submit").click(no_wait_after=True)
             try:
                 page.wait_for_url(
@@ -419,26 +394,21 @@ def _submit_headless(
                     submit_error = "Submit failed: page did not navigate"
         except Exception as e:
             submit_error = str(e)
-        finally:
-            if tmp_path:
-                try:
-                    os.unlink(tmp_path)
-                except OSError:
-                    pass
 
     try:
         with StealthySession(
             headless=True,
             timeout=BROWSER_SESSION_TIMEOUT,
             google_search=False,
-            cookies=saved_cookies,
+            cookies=saved_cookies if (cookie_cache.exists() and not _retried) else [],
         ) as session:
-            print(json.dumps({"status": "checking_login"}), flush=True)
+            if not (cookie_cache.exists() and not _retried):
-            session.fetch(
+                print(json.dumps({"status": "checking_login"}), flush=True)
-                f"{BASE_URL}/",
+                session.fetch(
-                page_action=check_login,
+                    f"{BASE_URL}/",
-                network_idle=True,
+                    page_action=check_login,
-            )
+                    network_idle=True,
+                )
 
             if not logged_in:
                 print(json.dumps({"status": "logging_in"}), flush=True)
@@ -456,7 +426,7 @@ def _submit_headless(
             session.fetch(
                 f"{BASE_URL}/contest/{contest_id}/submit",
                 page_action=submit_action,
-                solve_cloudflare=True,
+                solve_cloudflare=False,
             )
 
             try:
@@ -466,15 +436,21 @@ def _submit_headless(
             except Exception:
                 pass
 
-            if submit_error:
+        if needs_relogin and not _retried:
-                return SubmitResult(success=False, error=submit_error)
+            cookie_cache.unlink(missing_ok=True)
-
+            return _submit_headless(
-            return SubmitResult(
+                contest_id, problem_id, source_code, language_id, credentials, _retried=True
-                success=True,
-                error="",
-                submission_id="",
-                verdict="submitted",
             )
+
+        if submit_error:
+            return SubmitResult(success=False, error=submit_error)
+
+        return SubmitResult(
+            success=True,
+            error="",
+            submission_id="",
+            verdict="submitted",
+        )
     except Exception as e:
         return SubmitResult(success=False, error=str(e))