try-gstack/TODOS.md

TODOS

Tracked work, organized by component then priority (P0 highest → P4 lowest). See ~/.gstack/projects/tiennm99-try-gstack/tiennm99-main-design-20260429-160610.md for the full plan.

Distribution & Validation (Phase 0, pre-build)

• Phase 0 SERP audit Priority: P0 What: 2-hour Google.com.vn / YouTube VN / TikTok VN audit on góc nội tiếp, tam giác bằng nhau, tam giác đồng dạng. Document positions 1–10 + dominant content type. Why: Determines whether text page can win SERP or whether we pivot to video-first. Output: competitive-landscape.md companion file.

• Phase 0 TikTok / Shorts validation Priority: P0 What: 5 short videos (10–30s) of mock drag interactions (Figma + Lottie + screen-record). Post to test the visual-wow thesis BEFORE writing module code. Why: If videos flop, the entire visualizer wedge is dead before a weekend is invested.

• Vetted Facebook group entry Priority: P1 What: Join "Hỏi đáp Toán THCS", "Toán học vui", "Giáo viên Toán". Post one helpful, non-self-promotional answer in each. Earn standing. Why: Distribution plan depends on these groups; founder must have presence before the launch post.

TheoremCanvas primitive (weekend 1, before any module)

• Build TheoremCanvas as single HTML file first Priority: P1 What: <TheoremCanvas mode="..." initial={...} client:visible /> API. SVG canvas + Pointer Events drag + setPointerCapture per vertex. AbortController teardown. Per autoplan eng decision E1. Where: prototype as standalone prototype.html, then port into src/components/TheoremCanvas.astro once API feels right.

• Vertex drag affordance + 48px hit-target Priority: P1 What: 14px filled circle, 2px white stroke, 4px drop shadow, 48px transparent square hit-target, tabindex=0, focused = 3px #D7263D ring. Per Design Decision D1.

• Keyboard navigation for vertices Priority: P1 What: Tab cycles vertices; arrows ±4px; shift+arrow ±16px; Enter snaps to nearest interesting position. Per Design F6.1.

Module 3 — Lớp 9 Góc nội tiếp (weekend 2, hero module)

• Theorem panel + 3 worked SGK-style examples Priority: P1 Status: PARTIAL — v0.0.2.0 ships theorem panel + 1 worked example. 2 more examples remain.

• First-load coaching state (per Design F2.2) Priority: P2 What: Animated ghost-finger gesture for 1.5s, "Kéo điểm M để khám phá" caption, dismissible, persisted in localStorage.

• ARIA-live announcements on dragend Priority: P2 What: "Góc AMB bằng 47 độ" announced via aria-live="polite". Per Design F6.4.

• Multi-toggle theorem variants Priority: P2 What: Toggle between "góc nội tiếp" / "góc nội tiếp chắn nửa đường tròn = 90°" / "góc tạo bởi tiếp tuyến và dây cung". Each variant uses the same canvas with different fixed-point setup.

• KaTeX inline rendering for theorem text Priority: P3 What: Currently uses Unicode (∠AMB, °) which renders fine in Be Vietnam Pro. Switch to KaTeX when notation gets richer (cung, đường tròn (O), etc.).

Module 1 — Lớp 7 Tam giác bằng nhau

• SAS / ASA / AAS / cạnh huyền-góc nhọn / cạnh huyền-cạnh góc vuông toggles Priority: P2 What: SSS shipped in v0.0.3.0. Add the other 5 cases as toggles on the same canvas — toggling switches which sides/angles get the matched encoding and which detector runs.

• More worked examples (Module 1) Priority: P3 What: v0.0.3.0 ships 1 example. SGK textbook has many. Add 2 more.

Module 2 — Lớp 8 Tam giác đồng dạng (weekend 4)

• Similarity ratio + AA/SAS/SSS-similar detectors Priority: P1 What: src/geom-engine/similarity.ts. Live ratio display via numeric text-node updates only (KaTeX template rendered at build, never re-parsed during drag).

• Scale slider clamped to [0.5, 2.0] Priority: P1 What: min=0.5, max=2, step=0.05. Cannot reach 0. Per Eng failure mode #3.

Testing & CI infrastructure (with first canvas module)

• fast-check property tests Priority: P1 What: ∀ M on arc, |∠AMB − ∠AM₀B| < 0.5° (inscribed-angle invariance). ∀ pointer, dist(projectToCircle(p, c), c.center) = c.r ± ε.

• Playwright e2e + multi-touch tests Priority: P1 What: Per-module happy-path + keyboard-path + multi-touch-path. Use device: 'Pixel 5' for touch profiles. Per autoplan test plan.

• size-limit bundle gate Priority: P2 What: 200KB gz JS / 50KB gz CSS / 80KB woff2 fonts. CI fail-fast.

• Lighthouse-CI gate Priority: P2 What: Mobile preset, ≥90 Perf + A11y. Run against bun preview.

• axe-playwright a11y tests Priority: P2 What: Zero axe-violations on every module page.

• Visual regression for tick-marks + Vietnamese diacritics Priority: P2 What: Argos / Playwright snapshot baselines.

Retention & Distribution (post-MVP)

• Zalo / Telegram subscribe CTA on every module Priority: P2 What: "Nhận theorem mới mỗi tuần" — turns hub into sequence. Per CEO finding (theme 4).

• Lớp-9 course-spine "next theorem" footer card Priority: P2 What: Each lớp-9 module links forward to next theorem. Per Design F3.5.

• OpenGraph image generation per module Priority: P2 What: Pre-rendered SVG-to-PNG of canvas hero state. Critical for FB / Zalo shares.

• Schema.org LearningResource meta Priority: P3 What: Per-module structured data for Google rich results.

Domain & infra (post-validation trigger)

• Buy .vn / .com.vn domain Priority: P1 What: TRIGGER: 500 sessions/30d OR 1 organic teacher share OR ≥5 modules shipped (per RUNBOOK). VN registration takes 7–14 days.

• Cloudflare Web Analytics Priority: P2 What: JS-injected, no cookies, no consent banner. Activate after first 50 daily sessions.

• PUBLIC_VERSION env wiring Priority: P3 What: Currently index.astro reads import.meta.env.PUBLIC_VERSION ?? '0.0.1.0' — env never set. Wire it from CI build (read VERSION file) so footer doesn't rot on bump.

Out of scope (deferred indefinitely or to v2)

• English / bilingual support
• Embed-as-iframe API (CSP frame-ancestors work)
• Comments via Giscus
• Account / auth / email capture
• Browser extension overlay (out of static scope)
• Anki-style spaced-repetition deck (different product shape)
• Print → digital QR bridge (distribution experiment, not engineering)
• Teacher-tool / B2B2C demo mode (build after Module 3 ships)

Completed

• Drag M around circle, project to circle constraint — src/components/inscribed-angle.ts + src/geom-engine/circle.ts:projectToCircle. Completed: v0.0.2.0 (2026-04-29)
• TheoremCanvas primitive first cut — vanilla TS in Astro <script> tag, AbortController teardown on astro:before-swap. Completed: v0.0.2.0 (2026-04-29). Note: built directly in Astro rather than as a single HTML prototype first; the inscribed-angle pattern proved the shape, and the next module (lớp 7 / 8) will reuse this pattern.
• SSS detector — src/geom-engine/triangle.ts:congruentSSS with position-strict semantics. 10 unit tests including symmetry and EPSILON tolerance. Completed: v0.0.3.0 (2026-04-30)
• SGK tick-mark encoding — 1/2/3 ticks paired with the locked 3-color palette, rendered live during drag. Wired in Module 1 (Tam giác bằng nhau). Completed: v0.0.3.0 (2026-04-30). Tick rendering helper in src/components/congruence-sss.ts:renderTicks is reusable for future modules.