Zsh script to generate social share images from an image

create-social-share-images.zsh

#!/usr/bin/env zsh

# version
VERSION="1.0.0"

# --- functions ---
print_help() {
  echo "Usage: $0 <input-image>"
  echo ""
  echo "Example:"
  echo "  $0 input.png"
  echo ""
  echo "Outputs:"
  echo "  gethired_share_rectangular.jpg (1200x630 ~1.91:1)"
  echo "  gethired_share_square.jpg      (1200x1200 1:1)"
}

# --- flags ---
if [[ "$1" == "-h" || "$1" == "--help" ]]; then
  print_help
  exit 0
fi

if [[ "$1" == "-v" || "$1" == "--version" ]]; then
  echo "$VERSION"
  exit 0
fi

# --- dependency check ---
if ! command -v magick >/dev/null 2>&1; then
  echo "Error: ImageMagick (magick) not found."
  echo "Install with:"
  echo "  brew install imagemagick"
  exit 1
fi

# --- input check ---
INPUT="$1"
if [[ -z "$INPUT" || ! -f "$INPUT" ]]; then
  echo "Error: input file missing or not found."
  print_help
  exit 1
fi

# --- Image 1: rectangular (contain, padded, ~1.91:1, final JPG) ---
magick "$INPUT" \
  -resize 1200x630 \
  -background none \
  -gravity center \
  -extent 1220x650 \
  -resize 1200x630 \
  -background white \
  -alpha remove -alpha off \
  gethired_share_rectangular.jpg

# --- Image 2: square (contain, padded, 1:1, final JPG) ---
magick "$INPUT" \
  -resize 1200x1200 \
  -background none \
  -gravity center \
  -extent 1220x1220 \
  -resize 1200x1200 \
  -background white \
  -alpha remove -alpha off \
  gethired_share_square.jpg