# Phase Z Region Layout Catalog (Internal Region structure)
#
# User lock (2026-05-07) — Step 8-A:
#   Internal Region (= child zone) layout vocabulary catalog.
#   Source: docs/architecture/PHASE-Z-CONTENT-OBJECT-SUBZONE-SPEC.md §2.5 (v1, 6 entry).
# Code connection (2026-05-08, Step 8-conn):
#   src/phase_z2_composition.py::load_region_layouts() reads this file.
#   src/phase_z2_pipeline.py step08 artifact records select_region_layout_candidates() output
#   per zone (placeholder signals: region_count=1, Step 3/4 부재 종속).
#   Step 9 v0 (application_plan) consumes the candidate list per unit.
#
# Hierarchy:
#   Slide -> Layout (slide-body zone 분배)
#     -> Zone -> Internal Region (this catalog) -> Frame -> Frame Slot -> Content
#
# Decision rule (SPEC §2.5 deterministic, AI X):
#   1. region_count == 1                                   -> region-single
#   2. details_presence == true / large content            -> region-preview-details
#   3. region_count == 4 AND 4 equal items                 -> region-grid-2x2
#   4. region_count == 2 AND primary+supporting + ratio    -> region-main-support
#   5. region_count == 2 AND visual element (image/diagram)-> region-horizontal-split
#   6. fallback                                            -> region-vertical-stack
#
# Per-entry fields:
#   region_count: int | str  (e.g. 1, 2, 4, "2+")
#   topology: vertical | horizontal | grid | weighted | preview-details | single
#   default_fallback: bool   (true only for region-vertical-stack — SPEC §2.5)
#   description: str
#   candidate_when: dict     (decision rule signals — Step 8-B input)


region-single:
  region_count: 1
  topology: single
  default_fallback: false
  description: 1 region (zone entire = single region)
  candidate_when:
    region_count: 1


region-vertical-stack:
  region_count: "2+"
  topology: vertical
  default_fallback: true
  description: Vertical top-bottom stack. Default fallback when no other rule matches.
  candidate_when:
    region_count_ge: 2
    flow_type: sequential


region-horizontal-split:
  region_count: 2
  topology: horizontal
  default_fallback: false
  description: Left-right horizontal split (text + image, text + diagram).
  candidate_when:
    region_count: 2
    has_visual_element: true   # image / diagram in content_type_mix


region-main-support:
  region_count: 2
  topology: weighted
  default_fallback: false
  description: Main region + supporting region (asymmetric ratio, e.g. 0.7 / 0.3).
  ratios_default: [0.7, 0.3]
  candidate_when:
    region_count: 2
    role_pattern: primary_supporting
    ratio_asymmetric: true        # max / min >= 2


region-preview-details:
  region_count: 2
  topology: preview-details
  default_fallback: false
  description: Inline preview region + details/popup region.
  # preserves_original 은 display_strategies.yaml 의 책임 (axis 분리 lock 2026-05-07).
  # User lock (원문 무손실 보존) 은 display_strategies 의 inline_preview_with_details
  # / details_only 의 preserves_original: true 로 single source of truth 박힘.
  candidate_when:
    or:
      - details_presence: true
      - large_table: ">= 5 rows"
      - long_text: true


region-grid-2x2:
  region_count: 4
  topology: grid
  default_fallback: false
  description: 2x2 grid (4 equal regions).
  candidate_when:
    region_count: 4
    flow_type: parallel_4