Files
ersatztv/docs
timothy 1641ca8305 fix(578): the LIKE prefilter under-matched every accented artist; make the superset provable
Review of 1b78dc9e found the pre-filter's correctness claim was false, and the claim was in the
decision record as well as the code.

F1 (high). The pattern JSON-encoded the whole query prefix on the reasoning that the stored text
escapes non-ASCII, so encoding the prefix the same way would line up. It does not: SQL LOWER()
lowercases the *escape text* (`É` -> `é`); it cannot case-fold the codepoint that escape
denotes. So `q=é` built `%"é%`, the stored `Édith Piaf` never matched, and the row was
discarded before the in-memory filter could accept it. Every accented artist — Beyoncé, Björk,
Sigur Rós, Édith Piaf — was silently unsuggestable, which in a music library is the common case.

The invariant that was missing, now stated in the code: the SQL pre-filter is an OPTIMIZATION. It
may over-match; it must never under-match. Correctness lives in the in-memory filter. So the pattern
now narrows only on the leading run of characters the JSON writer stores verbatim and stops at the
first character it cannot prove — `q=Beyoncé` still narrows on `beyonc`, `q=é` narrows on nothing
and leans on the row cap. Soundness rests on two facts now asserted by exhaustive computation rather
than argued: no non-ASCII codepoint in U+0080..U+10FFFF OrdinalIgnoreCase-equals a printable ASCII
character (false for InvariantCultureIgnoreCase, which folds ~190 — the choice of Ordinal is
load-bearing), and the exact set of ASCII the encoder escapes.

F1b. `UseRequestLocalization` honours Accept-Language, so the culture was caller-controlled and
`ToLower()` plus the default linguistic `StartsWith(string)` let a header change the answer.
Comparison is now OrdinalIgnoreCase and ordering StringComparer.Ordinal throughout — including the
shared FilterSortTake that state/video_dynamic_range/content_rating also use. Sets unchanged,
order now ordinal rather than culture-dependent.

F2. The merge comment asserted an exactness the code does not have: sources truncate by their own
ordering (DB collation / primary key), not the merge's, so a dropped value can outrank a survivor.
Comment and record now say best-effort, exact only below the truncation points.

F3/F4. The cap now rides `ORDER BY Id` rather than the JSON column: MySQL sorts TEXT by only
max_sort_length bytes, so the old ordering was not deterministic there, and sorting the whole
matching set was avoidable work. What the cap still does NOT bound is the scan — a leading-wildcard
LIKE cannot seek an index — so that cost is now documented as accepted, with a normalized
`SongArtist` table named as the follow-up candidate rather than left implicit.

Every clause above is covered by a test verified to FAIL when that clause is mutated (old pattern
builder: 5 red; culture chain: 3 red; cap=3 / cap=limit / ORDER BY json / no cap: red each).

F5. Converted to a proper supersession. The old record did not merely hold a stale fact — it
recorded song/music-video credits as an "intentionally-uncovered gap" and album_artist as
unsupported, and this reverses that call, which `docs.decision-lifecycle` says is never a
line-edit. `api.search-field-values` is archived with its original prose restored, and
`api.search-field-values-sources` replaces it carrying the whole endpoint contract.
2026-07-27 03:10:35 +02:00
..

docs/ — task-signal map

Purpose: route a fresh contributor/agent to the minimal set of docs for the task at hand, instead of a mandatory front-to-back read. Update this doc in the same PR that adds, removes, or retitles a doc below, or that changes which sections a task signal points to.

Start here, always

  • CLAUDE.md (repo root) — project intro: architecture, layout, dev commands, conventions, Task Completion Protocol.
  • docs/contributing.md — established code patterns (CQRS/MediatR, LanguageExt, the ChicoryTV SPA, EF Core dual-provider migrations, FFmpeg pipeline, analyzers, testing). Read before any non-trivial change.

Task signal → minimal sections

Signal Read
Session startup / "what's next" (no issue named) docs/handoffs/chicorytv-issue-queue.md (standing kickoff — two concurrent tracks: orientation ‖ scripts/select-queue.sh 5)
Named-issue pickup Skip queue selection; go straight to focused retrieval — see "Knowledge retrieval" below, then the issue body
Adding/changing a /api/* endpoint docs/api-conventions.md checklist + docs/endpoint-index.md
Adding a ChicoryTV SPA screen docs/spa-conventions.md
Scheduling / playout engine work docs/domain-model.md + decisions catalog rows keyed sched.* (docs/decisions/README.md)
Concurrency / optimistic-locking work docs/api-conventions.md §7a/b/c + docs/decisions/optimistic-concurrency.md
Auth / security-surface work docs/decisions/api-auth-security.md
CI / release pipeline work docs/ci-cd.md + docs/decisions/release-ci-governance.md
Live local run / Playwright-MCP verification docs/e2e-local.md + scripts/e2e-local.sh
Adding/changing a UI-E2E browser flow docs/e2e-local.md → "UI-E2E harness" + scripts/e2e-ui.sh
What does a test suite cover docs/testing.md
Legacy Blazor route lookup docs/blazor-route-parity.md (historical #91 phase (b) inventory)
"Why do we do X this way" / challenging a convention Catalog-first: docs/decisions/README.md (active rows) → follow the row's link to docs/decisions/records/<area>/<topic>.md for full rationale. docs/decisions/archive/<area>/ only for "what did the rule used to be."

Knowledge retrieval (MemPalace + catalog + Gitea)

These four rules are the seam agreed with server-management#642 (the Gitea→MemPalace exporter). They apply whether the question comes up via MemPalace, a grep, or a stale comment:

  1. Current conventions/decisions → catalog-first. Start at docs/decisions/README.md; discover via the ErsatzTV-Decisions wing (active) / ErsatzTV-Decisions-Archive (superseded/retired). Resolve by topic/key, never by chasing a file path.
  2. Issue history → evidence, not authority. The Gitea-ErsatzTV wing is historical narrative that may be stale; it never overrides current Markdown.
  3. The breadcrumb rule (the crux behavior change). A file path named inside a historical issue comment (e.g. "grep docs/decisions.md 2026-07-17", "see …") is a breadcrumb, not a live pointer. Find the current rule via the catalog / active wing by concept; do not treat the named path as current. (Why it's safe: still-current → in the active wing, breadcrumb resolves; superseded → the active wing returns the successor and a literal follow lands on a record that announces its own status: superseded; retired → the active wing returns nothing, which is itself the signal. The validator-enforced move-to-archive/ is what prevents the catastrophic "superseded rule read as current" case.)
  4. Fallback when MemPalace is stale/down: docs/decisions/README.md catalog, then rg '^`key: <dotted.key>`' docs/decisions/. MemPalace is never authority nor sole fallback.

MemPalace is candidate discovery only — every passage is verified against its cited Markdown/Gitea source before use. Never derive live queue state from MemPalace, #237, or historical comments; queue state is live Gitea state, retrieved via scripts/select-queue.sh (see docs/handoffs/chicorytv-issue-queue.md). Full retrieval contract (altitude/precedence, staleness bounds, what's mined per issue): docs/handoffs/chicorytv-issue-queue.md → "Knowledge retrieval".

Also present in docs/

  • docs/domain-model.md — what the app IS: entity glossary, channel→playout→schedule/block concept map, where each concept is edited in the SPA.
  • docs/api-conventions.md — checklist for adding/changing a /api/* endpoint (controllers, DTOs, error mapping, auth, OpenAPI regen, tests).
  • docs/spa-conventions.md — playbook for adding a screen to the ChicoryTV React SPA.
  • docs/e2e-local.md (+ scripts/e2e-local.sh) — how to run a live local instance for manual or Playwright-MCP verification.
  • docs/testing.md — testing map: what each *.Tests project / web suite covers, golden-file nets, the timezone-independence rule, how to run subsets, the per-PR verification gate.
  • docs/blazor-route-parity.md — historical record of the completed #91 phase (b) cutover: the Blazor Server UI is removed and every legacy route now 302-redirects to its SPA equivalent (or falls through to the catch-all → /app). Read it for the full legacy→SPA route inventory.
  • docs/decisions/records/<area>/<topic>.md — one active decision record per file, YAML frontmatter (key/title/status/since/supersedes/superseded-by, plus optional stale-after/sources — ersatztv#603), rationale prose in the body. The filename is the key, so one-active-record-per-key is a filesystem property (ersatztv#610). docs/decisions.md and the topic files remain as the lifecycle-schema narrative plus a "Records formerly in this file" index, which is what keeps older date-based pointers resolvable. Generated active view: docs/decisions/README.md (catalog / task router) — start there. Superseded/retired records live in docs/decisions/archive/ and are read only for history, never for "what is the current rule."
  • docs/ci-cd.md — build/test/release pipeline, versioning, dependency management.
  • docs/rest-api.md — REST API design doc for ersatztv#2 (goals, conventions, per-slice plan). Largely superseded day-to-day by docs/api-conventions.md; read this for the original rationale.
  • docs/mcp.md — the ErsatzTV.Mcp stdio JSON-RPC MCP server (#58): how it wraps /api/v1 as read + cautious-write tools, its config/env vars, auth, security posture, and the tool catalog.
  • docs/channels.md — Channel entity field reference.
  • docs/m3u-xmltv.md — M3U/XMLTV generation overview (ChannelPlaylist, GetChannelGuideHandler).
  • docs/fork-strategy.md — divergence policy vs upstream ErsatzTV.
  • docs/design-sync.md — Claude Design ↔ repo screen workflow (#92).
  • docs/endpoint-index.md — generated REST endpoint index (method/path/operationId/summary per OpenAPI tag). Do not edit by hand; regenerated by scripts/generate-endpoint-index.py / scripts/update-openapi.sh.
  • docs/handoffs/chicorytv-issue-queue.md — static session kickoff prompt + workflow lore. Queue state is live Gitea state, retrieved each session via scripts/select-queue.sh — see that file's standing kickoff for the two concurrent tracks (orientation ‖ selection). ersatztv#237 is a closed, archival historical tracker (superseded by startup.parallel-orientation in docs/decisions.md) — not a live pointer.
  • docs/tracker-retrofit-triage-237.md — audit trail for the #524 triage of ersatztv#237's 111 comments (method, per-comment classification, totals). Evidence for the docs.tracker-comment-retrofit decision; read it only when triaging another over-cap tracker.
  • docs/handoffs/rest-api.md — original handoff prompt for kicking off the REST API work (#2).