# -*- coding: utf-8 -*-
"""Host-side guard for issue #23's `live` kv contract.

The issue (owner, 2026-09-07: "啥叫JS活儿？html写不了？" -- the front end is
ours, so write it): a kv row that sums a row table -- the Reinforcement
page's Strand count, Total IP and Aps -- must follow the table's rows IN
THE BROWSER as they are edited, not only on the next page build / Run.
The page is plain ES2017 in a static file with no JS test runner, so this
suite checks the CONTRACT by reading the source, the same way
`test_button_tooltips.py` reads `bundle.yaml` / `script.py`: the three
pieces that wire the feature together must all exist and stay connected --
`renderKv` records the spec into `state.liveKv`, `recomputeLiveKv` rewrites
the value cells, and `updateValue` (plus the row add/remove handlers) calls
it whenever a key of the table changes. And the spec document must still
describe the row shape (docs/pa-web-spec.md, "kv").
"""
import io
import os
import re

_EXT = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
_REPO = os.path.dirname(_EXT)

APP_JS = os.path.join(_REPO, 'tools', 'pa_web', 'static', 'app.js')
SPEC_MD = os.path.join(_REPO, 'docs', 'pa-web-spec.md')


def _read(path):
    with io.open(path, encoding='utf-8') as f:
        return f.read()


def test_the_files_this_guards_still_exist():
    """If the page moves, this suite must fail loudly rather than pass by
    reading nothing -- the test_button_tooltips.py discipline."""
    assert os.path.isfile(APP_JS), 'missing {0}'.format(APP_JS)
    assert os.path.isfile(SPEC_MD), 'missing {0}'.format(SPEC_MD)


def test_app_js_declares_the_live_kv_mechanism():
    src = _read(APP_JS)
    # renderKv records rows into state.liveKv, keyed by the spec's table...
    assert 'state.liveKv' in src
    assert 'function recomputeLiveKv' in src
    # ...the value formatting helper exists, and row discovery is the SAME
    # helper the editable table itself uses (one idea of "present row").
    assert 'function fmtLive' in src
    assert 'rowIds(live.table)' in src


def test_update_value_recomputes_live_kv_rows():
    """`updateValue` -- every cell edit's one funnel -- must call
    `recomputeLiveKv`, not just `recomputeDerived`. Sliced to updateValue's
    own body so a stray later call elsewhere cannot satisfy the guard."""
    src = _read(APP_JS)
    start = src.index('function updateValue')
    end = src.find('\n\n  // ---', start)
    assert end != -1, 'could not find the end of updateValue\'s body'
    body = src[start:end]
    assert 'recomputeLiveKv(' in body, \
        'updateValue no longer calls recomputeLiveKv after recomputeDerived'


def test_spec_documents_live_under_kv():
    md = _read(SPEC_MD)
    start = md.index('### `kv`')
    nxt = md.find('\n### ', start + 1)
    assert nxt != -1, 'no section follows kv in pa-web-spec.md'
    section = md[start:nxt]
    assert re.search(r'\[label, value, live\]', section)
    assert '"live"' in section
    assert '"terms"' in section and '"format"' in section
    assert '"unknown"' in section
    # the contract names the trigger: any key of the table, add/remove row
    # included, and JS-off correctness (server value is the first paint).
    assert '.present' in section
    assert 'JS off' in section