#!/bin/bash


DIRECTORY="$(readlink -f "$(dirname "$0")")"
trap "exit 1" TERM
export TOP_PID=$$

error() {
  echo -e "\e[91m$1\e[39m" 1>&2
  kill -w -s TERM $TOP_PID
  exit 1
}

#$1 is a quotation-marked, space-seperated list of package names.
#$2 is the path to the program folder being installed.
#Example usage: ~/pi-apps/pkg-install "gparted buffer expect" ~/pi-apps/apps/Arduino

PKG_LIST="$1" #quotation-marked, space-seperated list of package names to install
app="$(basename "$2")" #remove any slashes to just get program name


reduceapt() { #remove unwanted lines from apt output
  grep -v "apt does not have a stable CLI interface.\|Reading package lists...\|Building dependency tree\|Reading state information...\|Need to get\|After this operation,\|Get:\|Fetched\|Selecting previously unselected package\|Preparing to unpack\|Unpacking \|Setting up \|Processing triggers for "
}

echo "Running pkg-install..."

if [ -z "$PKG_LIST" ];then
  error "No package names specified to pkg-install!"
elif [ -z "$app" ];then
  error "No app name specified to pkg-install!"
fi

echo -n "Waiting until APT locks are released... "
{
while sudo fuser /var/lib/dpkg/lock &>/dev/null ; do
  sleep 0.5
done
while sudo fuser /var/lib/apt/lists/lock &>/dev/null ; do
  sleep 0.5
done
if [ -f /var/log/unattended-upgrades/unattended-upgrades.log ]; then
  while sudo fuser /var/log/unattended-upgrades/unattended-upgrades.log &>/dev/null ; do
    sleep 0.5
  done
fi
echo "Done"
}

#sudo apt update
{
echo -e "Running \e[4msudo a\e[0mp\e[4mt u\e[0mp\e[4mdate\e[0m..."
output="$(sudo LANG=C LC_ALL=C apt update 2>&1)"
exitcode=$?

#inform user about autoremovable packages
if [ ! -z "$(echo "$output" | grep 'autoremove to remove them' )" ];then
  echo -e "\e[33mSome packages are unnecessary.\e[39m Please consider running \e[4msudo apt autoremove\e[0m."
fi

#inform user packages are upgradeable
if [ ! -z "$(echo "$output" | grep 'packages can be upgraded' )" ];then
  echo -e "\e[33mSome packages can be upgraded.\e[39m Please consider running \e[4msudo apt full-upgrade\e[0m."
fi

#exit on apt error
errors="$(echo "$output" | grep '^[(W)|(E)|(Err]:')"
if [ $exitcode != 0 ] || [ ! -z "$errors" ];then
  echo -e "\e[91mpkg-install failed to run \e[4msudo apt update\e[0m\e[39m!"
  echo -e "APT reported these errors:\n\e[91m$errors\e[39m"
  exit 1
fi
}

#workarounds for local debs
{
for package in $PKG_LIST ;do
  
  #if package begins with / (absolute path)
  if [[ "$package" == /* ]];then 
    #determine the package name from the package filepath
    packagename="$(dpkg-deb -I "$package" | grep "^ Package:" | awk '{print $2}')"
    [ -z "$packagename" ] && error "pkg-install: failed to determine the package name of $package"
    
    #change PKG_LIST to contain package name instead of package's absolute path
    PKG_LIST="$(echo "$PKG_LIST" | sed "s|$package|$packagename|")"
    
    echo -e "\e[97m\nInstalling local $packagename package...\e[39m"
    
    #install it and reduce apt's output and indent the output
    (sudo LANG=C LC_ALL=C apt install -y --no-install-recommends "$package" 2>&1 || error "pkg_install: While installing local packages, $package failed to install.") | reduceapt

    sudo apt-mark auto "$packagename" || error "pkg-install: failed to mark the $packagename package as autoremovable.\nlocal package path: $package"
    
  fi
  
done

#now PKG_LIST shouldn't contain any absolute file paths
if [[ "$PKG_LIST" == /* ]];then 
  error "pkg_install: failed to remove all absolute paths from the package list!\nContents of PKG_LIST:\n$PKG_LIST"
fi
}

#workarounds for regex (using '*')
{
for package in $PKG_LIST ;do

  #if package contains *
  if echo "$package" | grep -q '*' ;then 
    
    echo -e "\e[97m\n$package contains regex. Expanding it...\e[39m"
    
    list="$(apt-cache search "$package" | awk '{print $1}' | grep "$(echo "$package" | tr -d '*')" | tr '\n' ' ')"
    
    #change PKG_LIST to contain package name instead of package's absolute path
    PKG_LIST="$(echo "$PKG_LIST" | sed "s|$(echo "$package" | sed 's/*/\\*/g')|$list|g")"
    echo -e "\e[97m\npackage list is now: $PKG_LIST\e[39m"
  fi
done

#now PKG_LIST shouldn't contain any * characters
if echo "$PKG_LIST" | grep -q '*';then 
  error "pkg_install: failed to remove all regex from the package list!\nContents of PKG_LIST:\n$PKG_LIST"
fi
}

#format PKG_LIST - remove double spaces, preceding spaces, and trailing spaces.
PKG_LIST="$(echo "$PKG_LIST" | sed 's/  / /g' | sed 's/^ //g' | sed 's/ $//g')"

#create dummy deb
{
#create dummy apt package that depends on the packages this app requires
echo -e "\e[97m\nCreating dummy deb...\e[39m"
#to avoid issues with symbols and spaces in app names, we shasum the app name for use in apt
appnamehash="$(echo "$app" | md5sum | cut -c1-8 | awk '{print $1}')"

rm -rf ~/pi-apps-$appnamehash ~/pi-apps-$appnamehash.deb
mkdir -p ~/pi-apps-$appnamehash/DEBIAN
echo "Maintainer: Pi-Apps team
Name: $app
Description: Dummy package created by pi-apps to install dependencies for the '$app' app
Version: 1.0
Architecture: all
Priority: optional
Section: custom
Depends: $(echo "$PKG_LIST" | tr -d ',' | sed 's/ /, /g')
Package: pi-apps-$appnamehash" > ~/pi-apps-$appnamehash/DEBIAN/control

dpkg-deb --build ~/pi-apps-$appnamehash || error "pkg-install: failed to create dummy deb pi-apps-$appnamehash"
}

#install dummy deb
{
#ensure dummy deb isn't already installed
if dpkg -l pi-apps-$appnamehash &>/dev/null ;then
  echo -e "\e[97m\nDummy deb is already installed. Uninstalling it first...\e[39m"
  sudo apt purge -y pi-apps-$appnamehash || error "Failed to purge dummy deb (pi-apps-$appnamehash)"
  sudo apt update &>/dev/null
fi

echo -e "\e[97m\nInstalling dummy deb...\e[39m"
output="$(sudo apt-get install -y --no-install-recommends ~/pi-apps-$appnamehash.deb 2>&1 | reduceapt | tee /dev/stderr )"
rm -f ~/pi-apps-$appnamehash.deb

echo -e "\e[97m\nApt finished.\e[39m"

errors="$(echo "$output" | grep '^[(W)|(E)|(Err]:')"
if [ ! -z "$errors" ];then
  echo -e "\e[91mFailed to install the packages!\e[39m"
  echo -e "APT reported these errors:\n\e[91m$errors\e[39m"
  exit 1
fi
}

#re-check package list. This time it should be blank.
{
INSTALL_LIST="$(sudo LANG=C LC_ALL=C apt-get install --no-install-recommends --dry-run $PKG_LIST 2>&1 | sed -n '/The following NEW packages/,/to remove/p' | sed -e '2,$!d' -e '$d' | tr -d '*' | tr '\n' ' ' | sed 's/The following.*//')"
if [ ! -z "$INSTALL_LIST" ];then
  error "APT did not exit with an error, but these packages failed to install somehow:\n$INSTALL_LIST\e[39m"
else
  echo -e "\e[32mAll packages were installed succesfully.\e[39m"
fi
}

rm -rf ~/pi-apps-$appnamehash #remove dummy deb creation folder if all went well