#!/bin/sh -eu
in=$1

# Optional second argument: explicit output file. Made absolute here because we
# may cd into the input's directory below. Further arguments are ignored.
out_arg=""
if [ $# -ge 2 ]; then
  out_arg=", output='$(realpath -m "$2")'"
fi

doc=$in
backup_file=""
poster_lang=en

# For local files (not URLs): temporarily inject CSS that forces exact A0
# dimensions and prevents Chrome's print shrinking, and work from the file's
# directory so relative links (e.g. skeleton_files/) resolve.
if [ -f "$in" ]; then
  abs_in=$(realpath "$in")
  work_dir=$(dirname "$abs_in")

  # Language the poster is written in, from <html lang="…"> (posterdown copies
  # it from the Rmd `lang:` field). Used for the hyphenation check below.
  poster_lang=$(sed -n 's/.*<html[^>]*[[:space:]]lang="\([A-Za-z-]*\)".*/\1/p' "$in" | head -n1)
  poster_lang=${poster_lang:-en}

  backup_file="${abs_in}.backup"
  cp "$abs_in" "$backup_file"
  # Restore the original file when we exit, also on failure.
  trap '[ -n "$backup_file" ] && mv "$backup_file" "$abs_in"' EXIT

  sed -i '/<\/head>/i\
<style>\
@page { size: 841mm 1189mm !important; margin: 0mm 0mm 20mm 0mm !important; }\
html { width: 841mm !important; height: 1189mm !important; transform-origin: 0 0; }\
body { width: 841mm !important; height: 1189mm !important; margin: 0 !important; padding: 0 !important; overflow: hidden !important; line-height: 1.2 !important; }\
.poster { width: 841mm !important; height: 1189mm !important; }\
* { line-height: 1.2 !important; }\
p, div, span, li, ul, ol, td, th, a, strong, em, blockquote, caption, h1, h2, h3, h4, h5, h6 { line-height: 1.2 !important; }\
</style>' "$abs_in"

  cd "$work_dir"
  # pagedown accepts absolute local paths consistently across Chrome/container
  # versions; a bare basename can be rejected as an invalid URL.
  doc=$abs_in
fi

# --- Automatic hyphenation ---------------------------------------------------
# The template HTML carries `hyphens: auto` plus an <html lang="…"> attribute.
# Whether Chrome actually hyphenates depends on where it finds its hyphenation
# dictionaries:
#
#   * chrome-headless-shell (used in CI) BUNDLES the dictionaries in a
#     `hyphen-data` folder next to the binary and loads them automatically, so
#     hyphenation already works there without any help from us.
#   * full google-chrome (typical locally) ships the dictionaries as a
#     *component* living in the normal browser profile
#     (~/.config/google-chrome/hyphen-data). pagedown::chrome_print() launches
#     Chrome with a throwaway --user-data-dir that has no such component, so
#     hyphenation silently does nothing.
#
# For the local case we seed a persistent profile with that component and point
# Chrome at it: extra_args are appended after pagedown's own --user-data-dir and
# Chrome honours the last value of a repeated switch. We symlink the whole
# hyphen-data tree (all languages), so whatever `lang:` the poster declares is
# respected -- nothing here is English-specific.
lang_base=${poster_lang%%-*}

chrome_profile="${CHROME_PROFILE_DIR:-$HOME/.cache/pagedown-chrome-profile}"
user_data_dir_arg=""
for hyphen_src in \
    "$HOME/.config/google-chrome/hyphen-data" \
    "$HOME/.config/google-chrome-beta/hyphen-data" \
    "$HOME/.config/chromium/hyphen-data"; do
  [ -d "$hyphen_src" ] || continue
  mkdir -p "$chrome_profile"
  ln -sfn "$hyphen_src" "$chrome_profile/hyphen-data"
  # Only override the profile when we have something to seed; otherwise leave
  # pagedown's default (throwaway) profile so CI's bundled dictionaries load.
  user_data_dir_arg=",'--user-data-dir=$chrome_profile'"
  break
done

# Warn at build time if no dictionary for the poster's language is reachable,
# either from the seeded profile or bundled next to the Chrome binary pagedown
# will launch. Better a clear warning than a silently un-hyphenated poster.
chrome_bin=$(R --slave -e 'cat(pagedown::find_chrome())' 2>/dev/null || true)
bundled_dir="/nonexistent"
[ -n "$chrome_bin" ] && bundled_dir="$(dirname "$(readlink -f "$chrome_bin")")/hyphen-data"
have_dict=false
for dict in "$chrome_profile"/hyphen-data/*/hyph-"$lang_base"*.hyb \
            "$bundled_dir"/hyph-"$lang_base"*.hyb; do
  # Unmatched globs stay literal, so the file test simply fails for them.
  [ -e "$dict" ] && { have_dict=true; break; }
done
if $have_dict; then
  echo "html2pdf: hyphenation enabled for lang='$poster_lang'." >&2
else
  echo "html2pdf: WARNING - no hyphenation dictionary for lang='$poster_lang'; the PDF will not be hyphenated." >&2
fi

R -e "pagedown::chrome_print('$doc'$out_arg,
  options=list(
    pageRanges='1',
    paperWidth=33.11,
    paperHeight=46.81,
    marginTop=0,
    marginBottom=0,
    marginLeft=0,
    marginRight=0,
    printBackground=TRUE,
    scale=0.98,  # Compensate for ~2% print scaling
    displayHeaderFooter=FALSE,
    preferCSSPageSize=TRUE
  ),
  extra_args = c(
    '--disable-gpu',
    '--no-sandbox',
    '--disable-dev-shm-usage',
    '--force-device-scale-factor=1',
    '--disable-print-preview',
    '--disable-background-timer-throttling',
    '--allow-file-access-from-files',
    '--force-color-profile=srgb',
    '--disable-lcd-text',
    '--disable-font-subpixel-positioning',
    '--run-all-compositor-stages-before-draw'$user_data_dir_arg
  )
)"