#!/usr/bin/env bash
set -euo pipefail

REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
OUTPUT_DIR="$REPO_ROOT/slides"
mkdir -p "$OUTPUT_DIR"

# Find all markdown files with marp: true frontmatter
SLIDES=()
while IFS= read -r f; do
  SLIDES+=("$f")
done < <(grep -rl "^marp: true" "$REPO_ROOT/docs" --include="*.md" 2>/dev/null || true)

if [ ${#SLIDES[@]} -eq 0 ]; then
  echo "No marp presentations found in docs/."
  exit 0
fi

echo "Found ${#SLIDES[@]} presentation(s):"
printf '  %s\n' "${SLIDES[@]}"

if command -v marp &>/dev/null; then
  marp --html --output "$OUTPUT_DIR/" "${SLIDES[@]}"
else
  echo "marp not found locally — using Docker (marpteam/marp-cli)..."
  REL_SLIDES=()
  for f in "${SLIDES[@]}"; do
    REL_SLIDES+=("${f#"$REPO_ROOT"/}")
  done
  docker run --rm \
    -v "$REPO_ROOT":/home/marp/app:ro \
    -v "$OUTPUT_DIR":/home/marp/output \
    marpteam/marp-cli --html --output /home/marp/output "${REL_SLIDES[@]}"
fi

echo "Done — slides in $OUTPUT_DIR/"