acn-slide-gen — Pipeline

/acn-slide-gen:generate runs a deterministic 6-phase pipeline. Each phase consumes the previous phase’s output. The pipeline drives toward a self-contained Python script that python-pptx executes against the chosen flavor’s template.

flowchart LR
    P0["Phase 0<br/>Decrypt"] --> P1["Phase 1<br/>Inspect Template"]
    P1 --> P2["Phase 2<br/>Reason About Layout"]
    P2 --> P3["Phase 3<br/>Parse Content"]
    P3 --> P4["Phase 4<br/>Generate Python Script"]
    P4 --> P5["Phase 5<br/>Verify Output"]

Phase 0 — Decrypt

Resolve the source PPTX path and confirm it’s readable.

• New Deck Mode: look up --flavor in the registry, resolve to template.pptx
• Modify Mode: use the <deck.pptx> argument directly
• Locate a venv (.venv-pptx/ → .venv/ → any with python-pptx), or fall back to creating /tmp/.venv-pptx
• Run ${CLAUDE_PLUGIN_ROOT}/scripts/decrypt_pptx.py "<path>" and handle exit codes 0/1/2/3 (decrypted / not-found / password-fail / DRM-blocked)

Phase 1 — Inspect Template

Extract shape geometry and theme tokens.

• inspect_slide.py "<path>" <slide_number> --json → shape inventory with EMU coordinates and properties
• inspect_theme.py "<path>" --json → theme color and font tokens
• Read the active flavor’s brand.md for branding rules

Phase 2 — Reason About Layout

Classify each shape into a semantic role: brand-label, section-label, title, description, content-card, divider-line, footer-banner, footer-item, background-shape, image, unknown. Tag each as static, parameterized, or repeating. New Deck Mode also catalogs all available layouts and maps content sections (# → cover, ## no body → divider, ## with body → content).

Phase 3 — Parse Content

Map markdown to layout zones.

• ## heading → slide boundary + title zone
• First short line after heading → section-label
• Paragraphs → description
• ### sub-sections / bullets → content-cards or footer-items
• Bold-prefixed bullets (**Title**: description) split into card title + body
• Image input: read via Claude vision, infer headings, bullets, and sections, map to zones
• Overflow: split across multiple slides, append (1/2), (2/2) suffixes
• Underflow: leave card slots unfilled (don’t insert empty shapes)

Phase 4 — Generate Python Script

Write a self-contained script to /tmp/slide_gen_<timestamp>.py that:

• Defines EMU constants from Phase 1 coordinates
• One xml_<role>() f-string function per shape role
• Uses schemeClr references — never hardcoded RGB — so shapes inherit theme color
• Strict border rule: never use <a:ln><a:solidFill/></a:ln> (empty solidFill inherits theme line color and produces unintended outlines); explicit color inside <a:solidFill> when a border is intended
• Helpers: _uid(), _esc(), _ext() for IDs, escaping, creation IDs
• build_slide() assembles shapes onto slide.shapes._spTree
• reorder_slides() if --after is specified

Branding compliance is verified pre-write against the flavor’s brand.md (fonts, colors, sentence-case headlines, left-aligned text, highlight rules, layout selection, color proportions).

Phase 5 — Verify Output

After the script runs, confirm slide count, per-slide shape count, and (if --after was used) slide ordering. Branding spot-check on cover layout, structural markers, and one content slide’s font and color compliance against brand.md.

The generated script is preserved at /tmp/slide_gen_*.py for debugging and reuse.

Pipeline scripts

Three Python helpers ship in ${CLAUDE_PLUGIN_ROOT}/scripts/:

• decrypt_pptx.py — strip DRM from password-protected files; exit codes signal status
• inspect_slide.py — dump layout geometry and shape properties to JSON
• inspect_theme.py — extract theme color and font tokens

The scripts are flavor-agnostic. Flavor specifics live in assets/flavors/<flavor>/brand.md — see Flavors.