#!/usr/bin/env bash
# Taken from https://github.com/vapor-ware/gimme-that/commit/7be1b559cb10be240e55dac555e32e9fea729ccf

# set -x
set -eo pipefail

# Colors for colorizing
RED='\033[0;31m'
GREEN='\033[0;32m'
PURPLE='\033[0;35m'
BLUE='\033[0;34m'
YELLOW='\033[0;33m'
NC='\033[0m'

# Storage for constants
TARGET_BIN=${TARGET_BIN:-"gitkube"}
# TODO: Make this dynamic
GITHUB_API=${GITHUB_API:-"https://api.github.com"}
TARGET_GITHUB_USER=${TARGET_GITHUB_USER:-"hasura"}
TARGET_GITHUB_REPO=${TARGET_GITHUB_REPO:-"gitkube"}
TARGET_PROJECT=${TARGET_PROJECT:-$TARGET_GITHUB_USER/$TARGET_GITHUB_REPO}
TARGET_INSTALL_PATH=${TARGET_INSTALL_PATH:-"/usr/local/bin"}
HOST_OS=${HOST_OS:-$(uname | tr '[:upper:]' '[:lower:]')}
if [[ $(uname -m) == "x86_64" ]]; then
  HOST_ARCH="amd64"
else
  HOST_ARCH=${HOST_ARCH:-$(uname -m)}
fi

# Check for root permission
touch ${TARGET_INSTALL_PATH}/.gimme &> /dev/null || (echo -e "${RED}Root access is required to install to ${YELLOW}${TARGET_INSTALL_PATH}${NC}" && exit 1)
rm ${TARGET_INSTALL_PATH}/.gimme

# Basic JSON matching
# TODO: Clean this up for god's sake!
function jsonVal {
    temp=`echo $1 | sed 's/\\\\\//\//g' | sed 's/[{}]//g' | awk -v k="text" '{n=split($0,a,","); for (i=1; i<=n; i++) print a[i]}' | sed 's/\"\:\"/\|/g' | sed 's/[\,]/ /g' | sed 's/\"//g' | grep -w $2 | sed 's|.*\:\(.*\)|\1|'`
    echo ${temp##*|}
}

# Check GitHub for the latest release
echo -e "${BLUE}Checking GitHub for the latest release of ${YELLOW}${TARGET_BIN}${NC}"
URI=${GITHUB_API}/repos/${TARGET_PROJECT}/releases/latest
RELEASE_RESPONSE=$(curl -L -S -s ${URI})

# Parse release info
RELEASE_TAG=$(jsonVal "${RELEASE_RESPONSE}" "tag_name")
# TODO: Make this more flexible
echo -e "${BLUE}Found release tag: ${YELLOW}${RELEASE_TAG}${NC}"
TARGET_STRING=${TARGET_BIN}_${HOST_OS}_${HOST_ARCH}
# echo -e $TARGET_STRING
# TODO: Ditto. This makes me uber sad.
echo -e "${BLUE}Downloading ${YELLOW}${TARGET_STRING}${NC}"
DOWNLOAD_URL="https://github.com/"${TARGET_PROJECT}"/releases/download/"${RELEASE_TAG}"/"${TARGET_STRING}
# echo -e $DOWNLOAD_URL

# Check if we have this already
if ! command -v ${TARGET_BIN}; then
  echo -e "${RED}No previous install found. Installing ${YELLOW}${TARGET_BIN}${NC}${RED} to ${TARGET_INSTALL_PATH}/${TARGET_BIN}${NC}"
  curl -s -S -L ${DOWNLOAD_URL} -o ${TARGET_INSTALL_PATH}/${TARGET_BIN}
  chmod +x ${TARGET_INSTALL_PATH}/${TARGET_BIN}
# TODO: Do some version checking here. Hash?
elif curl -s -S -L -z ${TARGET_INSTALL_PATH}/${TARGET_BIN} ${DOWNLOAD_URL} -o ${TARGET_INSTALL_PATH}/${TARGET_BIN} ; then
  echo -e "${RED}Newer binary found! Installing ${YELLOW}${TARGET_BIN}${NC}${RED} to ${TARGET_INSTALL_PATH}/${TARGET_BIN}${NC}"
  chmod +x ${TARGET_INSTALL_PATH}/${TARGET_BIN}
  exit 0
fi
echo -e "${GREEN}No newer version found. Leaving ${YELLOW}${TARGET_INSTALL_PATH}/${TARGET_BIN}${NC}${NC}"