#!/bin/sh

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
NO_COLOR='\033[0m'

CHECKING_OUT_BRANCH=$3
OLD_BRANCH=$1
NEW_BRANCH=$2

function ask_yes_or_no(){
  exec < /dev/tty
  while true; do
    read
    if [ "$REPLY" = "" ]; then
      REPLY='y'
    fi
    case $(echo $REPLY | tr '[A-Z]' '[a-z]') in
      y|yes) echo "yes"; break;;
      *)     echo "no" ; break;;
    esac
  done
}

if [ $CHECKING_OUT_BRANCH -eq 1 ]
  then
    FILES_CHANGED=`git diff $OLD_BRANCH $NEW_BRANCH --name-status`

    BUNDLE_CHANGED=`echo "$FILES_CHANGED" | egrep 'M\tGemfile.lock'`
    if [ ! -z "$BUNDLE_CHANGED" ]; then
      echo "\n ===> ⚠️  ${YELLOW}Your ${RED}Gemfile.lock ${YELLOW}has changed. Run 'bundle install'? [Y/n]${NO_COLOR}"
      if [[ 'yes' == $(ask_yes_or_no) ]]; then
	bundle
      else
        echo " ===> ⚠️  ${YELLOW} 'bundle install' skipped!${NO_COLOR}\n"
      fi
    fi

    MIGRATIONS_REMOVED=`echo "$FILES_CHANGED" | egrep 'D\tdb/migrate/([0-9]+)' | sort -r`
    MIGRATIONS_ADDED=`echo "$FILES_CHANGED" | egrep 'A\tdb/migrate/([0-9]+)'`

    if [ ! -z "$MIGRATIONS_REMOVED" ]; then
      echo "\n ===> 🌀  ${YELLOW}Some migrations need to be rolled back. Run migrations? [Y/n]${NO_COLOR}"

      if [[ 'yes' == $(ask_yes_or_no) ]]; then
	echo " ===> 🌀  ${GREEN}Running migrations...${NO_COLOR}\n"
        for migration in $MIGRATIONS_REMOVED
        do
          if [ $migration == "D" ]; then
            continue
          fi
          git checkout "$OLD_BRANCH" -- "$migration"
          VERSION=`echo "$migration" | cut -d'_' -f1 | cut -d'/' -f3`
          bundle exec rake db:migrate:down VERSION="$VERSION"
          git reset
          rm "$migration"
        done
        bundle exec rake db:test:prepare
        git checkout db/schema.rb
      else
	echo " ===> ⚠️  ${YELLOW} Migrations skipped!${NO_COLOR}"
      fi
    fi

    if [ ! -z "$MIGRATIONS_ADDED" ]; then
      echo "\n ===> 🌀  ${YELLOW}New migrations have been added. Run migrations? [Y/n]${NO_COLOR}"
      if [[ 'yes' == $(ask_yes_or_no) ]]; then
	echo " ===> 🌀  ${GREEN}Running migrations...${NO_COLOR}\n"
        bundle exec rake db:migrate db:test:prepare
      else
        echo " ===> ⚠️  ${YELLOW} Migrations skipped!${NO_COLOR}"
      fi
    fi

    echo "\n ===> ✅ ${GREEN} You're good to go!!!${NO_COLOR} 🍺\n"
fi