convert-assets.sh

#!/bin/bash

#
# Argument verification
#

if [[ $# < 2 ]]; then
  echo "Usage:" >&2
  echo "  convert-assets /assets /output" >&2
  exit 1
fi

ASSETS_DIR="$PWD/$1"
OUTPUT_DIR="$PWD/$2"

if [[ ! -d "$ASSETS_DIR" ]]; then
  echo "Assets directory $ASSETS_DIR does not exist" >&2
  exit 1
fi

if [[ ! -d "$OUTPUT_DIR" ]]; then
  echo "Output directory $OUTPUT_DIR does not exist" >&2
  exit 1
fi

#
# Conversion logic
#

CONVERT_PDF="gs -q -dNOPAUSE -dBATCH -sDEVICE=pngalpha -dEPSCrop -dTextAlphaBits=4 -dGraphicsAlphaBits=4 -dDownScaleFactor=3"

IMAGE_MODULE="$OUTPUT_DIR/Images.js"
IMAGE_OUTPUT_DIR="$OUTPUT_DIR/img"

echo "/* This module is automatically generated by convert-assets.sh */" > $IMAGE_MODULE
echo "/* https://github.com/isair/react-native-smart-assets */" >> $IMAGE_MODULE

echo "export default {" >> $IMAGE_MODULE

rm -rf "$IMAGE_OUTPUT_DIR"
mkdir "$IMAGE_OUTPUT_DIR"

for FILE_PATH in $ASSETS_DIR/*.pdf; do
  FILE="${FILE_PATH##*/}"
  FILE_NAME="${FILE%.*}"

  ( \
    $CONVERT_PDF -r216 -sOutputFile="$IMAGE_OUTPUT_DIR/$FILE_NAME".png "$FILE_PATH" ;\
    $CONVERT_PDF -r432 -sOutputFile="$IMAGE_OUTPUT_DIR/$FILE_NAME"@2x.png "$FILE_PATH" ;\
    $CONVERT_PDF -r648 -sOutputFile="$IMAGE_OUTPUT_DIR/$FILE_NAME"@3x.png "$FILE_PATH" \
  ) || true

  if [[ "$FILE_NAME" != "*" ]]; then
    # TODO: $PROPERTY_NAME from $FILE_NAME. Converting it to camel case if
    # necessary.
    echo "  $FILE_NAME: require('./img/$FILE_NAME.png')," >> $IMAGE_MODULE
  fi
done

for FILE_PATH in $ASSETS_DIR/*.{jpg,jpeg,png,gif}; do
  FILE="${FILE_PATH##*/}"
  FILE_NAME="${FILE%.*}"

  cp "$FILE_PATH" "$IMAGE_OUTPUT_DIR/$FILE" 2>/dev/null

  if [[ ("$FILE_NAME" != "*") && (! "$FILE_NAME" =~ "@") ]]; then
    echo "  $FILE_NAME: require('./img/$FILE')," >> $IMAGE_MODULE
  fi
done

echo "};" >> $IMAGE_MODULE