Problem: Submit read the source file in Lua, piped the full content as
stdin through to Python, then re-encoded it into an in-memory buffer
just to hand it back to the browser's file input. Unnecessary roundtrip
for AtCoder; CF also gains nothing from Lua owning the read.
Solution: Pass `source_file` path as a CLI arg to the scraper instead
of reading it in Lua and streaming via stdin. AtCoder calls
`page.set_input_files(file_path)` directly. Codeforces reads the file
with `Path(file_path).read_text()` before the browser session. Also
saves the buffer with `vim.cmd.update()` before submitting.
## Problem
AtCoder file upload always wrote a `.cpp` temp file regardless of
language. CF submit used `solve_cloudflare=True` on the submit page,
causing a spurious "No Cloudflare challenge found" error;
`_wait_for_gate_reload` in `login_action` was dead code. Stale cookies
caused silent auth failures with no recovery path. The `uv.spawn` ndjson
path for submit had no overall timeout.
## 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 login fast-path that skips the homepage 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. Add a 120s kill timer to
the ndjson `uv.spawn` submit path in `scraper.lua`.
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.
## Problem
Codeforces submit was a stub. CSES submit re-ran the full login flow on
every invocation (~1.5s overhead).
## Solution
**Codeforces**: headless browser submit via StealthySession (same
pattern as AtCoder). Solves Cloudflare Turnstile on login, uploads
source via file input, caches cookies at
`~/.cache/cp-nvim/codeforces-cookies.json` so repeat submits skip login.
**CSES**: persist the API token in credentials via a `credentials`
ndjson event. Subsequent submits validate the cached token with a single
GET before falling back to full login.
Also includes a vimdoc table of contents.
## Problem
`_submit_sync` was a 170-line nested closure with `_solve_turnstile` and
the browser-install block further nested inside it. Status events went
to
stderr, which `run_scraper()` silently discards, leaving the user with a
10–30s silent hang after credential entry. The NDJSON spawn path also
lacked stdin support, so submit had no streaming path at all.
## Solution
Extract `_TURNSTILE_JS`, `_solve_turnstile`, `_ensure_browser`, and
`_submit_headless` to module level in `atcoder.py`; status events
(`installing_browser`, `checking_login`, `logging_in`, `submitting`) now
print to stdout as NDJSON. Add stdin pipe support to the NDJSON spawn
path in `scraper.lua` and switch `M.submit` to streaming with an
`on_status` callback. Wire `on_status` in `submit.lua` to fire
`vim.notify` for each phase transition.
Problem: lua typecheck flagged missing start_time field on ContestSummary;
ty flagged BeautifulSoup Tag/NavigableString union on csrf_input.get(),
a 3-tuple unpack where _extract_problem_info now returns 4 values in
cses.py, and an untyped list assignment in usaco.py.
Solution: add start_time? to ContestSummary LuaDoc, guard csrf_input
with hasattr check and type: ignore, unpack precision from
_extract_problem_info in cses.py callers, and use cast() in usaco.py.
Problem: problem pages contain floating-point precision requirements and
contest start timestamps that were not being extracted or stored. The
submit workflow also needed a foundation in the scraper layer.
Solution: add extract_precision() to base.py and propagate through all
scrapers into cache. Add start_time to ContestSummary and extract it
from AtCoder and Codeforces. Add SubmitResult model, abstract submit()
method, submit CLI case with get_language_id() resolution, stdin/env_extra
support in run_scraper, and a full AtCoder submit implementation; stub
the remaining platforms.