## Problem
Wrong credentials produced garbled error messages (`"login failed: Login
failed: bad_credentials"`) and stale credentials remained cached after
failure, causing silent re-use on the next invocation.
## Solution
Standardize all scrapers to emit `"bad_credentials"` as a plain error
code, mapped to a human-readable string via `LOGIN_ERRORS` in
`constants.lua`. Fix `credentials.lua` to clear cached credentials on
failure in both the fresh-prompt and re-prompt paths. For AtCoder and
Codeforces, replace `wait_for_url` with `wait_for_function` to detect
the login error element immediately rather than sitting the full 10s
navigation timeout. Add "Remember me" checkbox on Codeforces login.
## Problem
On CSES, Kattis, and USACO, `:CP <platform> login` always prompted
for credentials and ran a full web login even when a valid session was
already cached. Submit also had weak stale-session detection.
## Solution
`credentials.lua` now tries cached credentials first before prompting,
delegating fast-path detection to each scraper. CSES `login()` checks
the cached API token and returns immediately if valid. USACO `login()`
and `submit()` call `_check_usaco_login()` upfront. Kattis `submit()`
emits `checking_login` consistently and also triggers re-auth on HTTP
400/403, not just on the `"Request validation failed"` text match.
The premature `Submitting...` log emitted by Lua before the scraper
started is removed — Python's own status events are sufficient.
## Problem
CodeChef had no working login, submit, or contest list. The browser
selectors were wrong, the contest list was missing present/past
contests,
and problem/contest URLs were unset.
## Solution
Fix login and submit selectors for the Drupal-based site. Paginate
`/api/list/contests/past` to collect all 228 Starters, then expand each
parent contest into individual division entries (e.g. `START228 (Div.
4)`).
Add language IDs, correct `url`/`contest_url`/`standings_url` in
metadata,
and make `:CP <platform>` open the contest picker directly.
## Problem
Codeforces language version IDs were wrong (pointed at old compiler
versions), `LANGUAGE_VERSIONS` was incomplete for most platforms, the
contest picker crashed when `supports_countdown` was stored as a
non-table entry, and `:CP stress` restored a broken IO view on exit.
## Solution
Correct CF `programTypeId` values and default to C++20. Add
`LANGUAGE_VERSIONS` entries for all six platforms. Guard
`get_contest_summaries` against non-table cache entries. Call
`ensure_io_view()` after stress session restore. Shorten the stress
terminal buffer name to a readable `term://stress.py` format.
## Problem
`LANGUAGE_VERSIONS` only covered cpp and python. Several platform IDs
were wrong — CodeChef used `C++ 17`/`Python 3` (correct: `C++`/`PYTH
3`), USACO listed nonexistent c++20/c++23 options, and CSES only had
C++17.
## Solution
Verify every platform's submit page and update all language ID tables.
Add java and rust entries where supported, fix incorrect CodeChef and
USACO IDs, and expand CSES `CSES_LANGUAGES` dict with
C++11/C++20/PyPy3/Java/Rust variants.
## Problem
Two gaps in the plugin: (1) contest pickers have no way to know whether
a contest supports countdown (race), so the UI can't surface that
affordance; (2) `:CP submit` hardcodes a single language ID per platform
with no way to choose C++ standard or override the platform ID.
## Solution
**Race countdown** (`4e709c8`): Add `supports_countdown` boolean to
`ContestListResult` and wire it through CSES/USACO scrapers, cache, race
module, and pickers.
**Language version selection** (`b90ac67`): Add `LANGUAGE_VERSIONS` and
`DEFAULT_VERSIONS` tables in `constants.lua`. Config gains `version` and
`submit_id` fields validated at setup time. `submit.lua` resolves the
effective config to a platform ID (priority: `submit_id` > `version` >
default). Helpdocs add `*cp-submit-language*` section. Tests cover
`LANGUAGE_IDS` completeness.
## Problem
`:CP <platform> login` short-circuited on cached cookies/tokens — if an
old session was still valid, the new credentials were never tested. The
user got "login successful" even with wrong input. USACO submit also
wasted a roundtrip on `_check_usaco_login` every time.
## Solution
Always validate credentials in the login path. Remove cookie/token
loading from `_login_headless` (AtCoder), `_login_headless_cf` (CF),
`_login_headless_codechef` (CodeChef), and `login` (CSES). For USACO
submit, replace the `_check_usaco_login` roundtrip with cookie trust +
retry-on-auth-failure (the Kattis pattern). Submit paths are unchanged —
cookie fast-paths remain for contest speed.
Closes#331
## Problem
There was no way to open a problem, contest, or standings page in the
browser from within the plugin.
## Solution
Add `contest_url` and `standings_url` to `MetadataResult` and persist
them in the cache. Add `cache.get_open_urls` to resolve all three URLs.
Wire up `:CP open [problem|contest|standings]` in `commands/init.lua`
to call `vim.ui.open`, warning when a URL is unavailable (e.g. CSES
has no standings). Closes#315.
## Problem
CSES `_web_login` used bare dict indexing on the API response, raising
an opaque `KeyError` on missing fields. `_check_token` swallowed all
exceptions as `False`, conflating transient network errors with invalid
tokens. CF persisted cookies unconditionally and silently swallowed
`_solve_turnstile` failures in `submit_action`.
## Solution
CSES API fields now use `.get()` with a descriptive `RuntimeError` on
absence. `_check_token` re-raises `httpx` network/timeout exceptions
so callers see real failures. CF cookie writes are guarded by an
`X-User-Handle` check (the CF auth cookie). `_solve_turnstile` errors
propagate to the outer error handler instead of being silenced.
## Problem
`:CP <platform> login` blindly caches username/password without
server-side
validation. Bad credentials are only discovered at submit time, which is
confusing and wastes a browser session.
## Solution
Wire `:CP <platform> login` through the scraper pipeline so each
platform
actually authenticates before persisting credentials. On failure, the
user
sees an error and nothing is cached.
- CSES: reuses `_check_token` (fast path) and `_web_login`; returns API
token
in `LoginResult.credentials` so subsequent submits skip re-auth.
- AtCoder/Codeforces: new `_login_headless` functions open a
StealthySession,
solve Turnstile/Cloudflare, fill the login form, and validate success by
checking for the logout link. Cookies only persist on confirmed login.
- CodeChef/Kattis/USACO: return "not yet implemented" errors.
- `scraper.lua`: generalizes submit-only guards (`needs_browser` flag)
to
cover both `submit` and `login` subcommands.
- `credentials.lua`: prompts for username/password, passes cached token
for
CSES fast path, shows ndjson status notifications, only caches on
success.
## Problem
After the initial submit hardening, two issues remained: source code was
read in Lua and piped as stdin to the scraper (unnecessary roundtrip
since
the file exists on disk), and CF's `page.fill()` timed out on the hidden
`textarea[name="source"]` because CodeMirror owns the editor state.
## Solution
Pass the source file path as a CLI arg instead — AtCoder calls
`page.set_input_files(file_path)` directly, CF reads it with
`Path(file_path).read_text()`. Fix CF source injection via
`page.evaluate()`
into the CodeMirror instance. Extract `BROWSER_SUBMIT_NAV_TIMEOUT` as a
per-platform `defaultdict` (CF defaults to 2× nav timeout). Save the
buffer
with `vim.cmd.update()` before submitting.
## 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
CSES submit was a stub returning "not yet implemented".
## Solution
Authenticate via web login + API token bridge (POST `/login` form, then
POST `/api/login` and confirm the auth page), submit source to
`/api/courses/problemset/submissions` with base64-encoded content, and
poll for verdict. Uses the same username/password credential model as
AtCoder — no browser dependencies needed. Tested end-to-end with a real
CSES account (verdict: `ACCEPTED`).
Also updates `scraper.lua` to pass the full ndjson event object to
`on_status` and handle `credentials` events for future platform use.
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.