#!/bin/bash

# mp-check | MatterLinux package check script
# MatterLinux 2023-2024 (https://matterlinux.xyz)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <https://www.gnu.org/licenses/>.

#############################
## import common functions ##
#############################
location=$(dirname "${0}")
location=$(realpath "${location}")
commonsh="$(echo "${location}" | sed 's/\/bin/\/lib/g')/mtsc-common.sh"

source "${commonsh}" > /dev/null

if [ "${?}" != "0" ]; then
  echo "Failed to import mtsc-common"
  exit 1
fi

#################
## global vars ##
#################
warnc=0
tmpdir="/tmp/.mp-clean"
required_files=(
  "DATA"
  "HASHES"
  "CHANGES"
  "files.tar.gz"
)
required_keys=(
  "version"
  "desc"
  "size"
)
root_dirs=(
  "boot"
  "etc"
  "mnt"
  "srv"
  "usr"
  "var"
  "opt"
)
bad_vars=(
  '$VERSION'
  '$ROOTDIR'
  '$NAME'
  '$DESC'
)

####################
## util functions ##
####################
# adds a new warning to the counter
add_warning(){
  warnc=$((warnc+1))
}

# cleans up the temp directoru
clean_tempdir(){
  rm -rf "${tmpdir}"
}

# recreates the temp directory
make_tempdir(){
  clean_tempdir
  mkdir "${tmpdir}"
}

# returns check status fail
fail_check(){
  clean_tempdir
  unset_indent

  error "${BOLD}Check ${RED}FAILED${RESET}"
  exit 1
}

# returns check status fail
success_check(){
  clean_tempdir
  unset_indent

  if [ "${warnc}" == "0" ]; then
    success "Check ${GREEN}SUCCESS${RESET}"
  elif [ "${warnc}" == "1" ]; then
    success "Check ${GREEN}SUCCESS${RESET}${BOLD} with ${YELLOW}${warnc}${RESET}${BOLD} warning${RESET}"
  else
    success "Check ${GREEN}SUCCESS${RESET}${BOLD} with ${YELLOW}${warnc}${RESET}${BOLD} warnings${RESET}"
  fi

  exit 0
}

# if the last command failed, print error and fail
check_ret_fail(){
  if [ $? -ne 0 ]; then
    if [ ! -z "$1" ]; then
      error "$1"
    fi
    fail_check
  fi
}

check_archive(){
  make_tempdir
  info "Extracting the archive"
  tar xf "${archivepath}" -C "${tmpdir}"
  check_ret_fail "Failed to extract the archive"

  info "Checking archive files"
  set_indent

  for f in "${required_files[@]}"; do
    if [ ! -f "${tmpdir}/${f}" ]; then
      error "Archive does not contain required file: ${BOLD}${f}${RESET}"
      fail_check
    fi
  done

  unset_indent
  info "Checking DATA file"
  set_indent

  for k in "${required_keys[@]}"; do
    local line_1="$(grep "^${k}=" "${tmpdir}/DATA")"
    local line_2="$(grep "^${k} =" "${tmpdir}/DATA")"

    if [ -z "${line_1}" ] && [ -z "${line_2}" ]; then
      error "File does not contain the required key: ${BOLD}${k}${RESET}"
      fail_check
    fi

    if [ "${k}" == "version" ]; then
      if [ ! -z "${line_1}" ]; then
        version="$(echo "${line_1}" | sed 's/version= //g')"
        version="$(echo "${version}" | sed 's/version=//g')"
      else
        version="$(echo "${line_2}" | sed 's/version = //g')"
        version="$(echo "${version}" | sed 's/version =//g')"
      fi

      if [ -z "${version}" ]; then
        error "Failed to obtain package version information"
        fail_check
      fi
    fi
  done

  name="$(head -n1 "${tmpdir}/DATA" | sed 's/\[//g')"
  name="$(echo "${name}" | sed 's/]//g')"

  if [ -z "${name}" ]; then
    error "Failed to obtain package name information"
    fail_check
  fi

  filename="${name}_${version}.mpf"

  success "Check was completed"
  unset_indent

  info "Checking HASHES file"
  set_indent

  while read l; do
    if [ -z "${l}" ]; then
      continue
    fi

    local hash_line="$(echo "${l}" | cut -d' ' -f1)"
    local file_line="$(echo "${l}" | cut -d' ' -f3)"

    if [ -z "${hash_line}" ] || [ -z "${file_line}" ]; then
      error "File contains an invalid formatted line"
      fail_check
    fi

    if [ "${#hash_line}" != "32" ]; then
      error "File contains an invalid MD5 hash"
      fail_check
    fi
  done < "${tmpdir}/HASHES"

  success "Check was completed"
  unset_indent

  info "Checking files.tar.gz archive"
  set_indent

  while read p; do
    if [ "${p:0:1}" == "." ] || [ "${p:0:1}" == "/" ]; then
      error "Root file location is invalid (${p:0:1})"
      fail_check
    fi

    local path_root="$(echo "${p}" | cut -d/ -f1)"
    local found=0

    for d in "${root_dirs[@]}"; do
      if [ "${path_root}" == "${d}" ]; then
        found=1
        break
      fi
    done

    if [ "${found}" == "0" ]; then
      error "Package files contains an unknown root directory: ${path_root}"
      fail_check
    fi
  done < <(tar tf "${tmpdir}/files.tar.gz")

  success "Check was completed"
  unset_indent

  info "Checking INSTALL file"
  set_indent

  if [ -f "${tmpdir}/INSTALL" ] && ! grep -q . "${tmpdir}/INSTALL"; then
    warn "Package contains an empty install script"
    add_warning
  fi

  success "Check was completed"
  unset_indent

  info "Checking CHANGES file"
  set_indent

  if ! grep -q . "${tmpdir}/CHANGES"; then
    warn "Changes file is empty"
    add_warning
  fi

  success "Check was completed"
  unset_indent

  info "Checking archive name"
  set_indent

  archivefile="$(basename "${archivepath}")"

  if [ "${archivefile}" != "${filename}" ]; then
    warn "Package archive name is not ideal (${archivefile} -> ${filename})"
    add_warning
  fi

  success "Check was completed"
  unset_indent
  clean_tempdir
}

check_source(){
  info "Checking the package script"
  set_indent

  if [ ! -f "${sourcepath}/pkg.sh" ]; then
    error "Package script does not exist"
    fail_check
  fi

  source "${sourcepath}/pkg.sh"
  check_ret_fail "Failed to source the package script"

  check_pkg_vars
  check_ret_fail

  if [ ${#DESC} -gt 200 ]; then
    error "Package description is too long (>200)"
    fail_check
  fi

  local desc_lower="${DESC,,}"
  local line_num=0

  if [[ "${DESC}" == *"contains"* ]] || [[ "${DESC}" == *"provides"* ]]; then
    warn "Avoid using words such as \"contains\" or \"provides\" in the package description"
    add_warning
  fi

  if type INSTALL &>/dev/null; then
    for v in "${bad_vars[@]}"; do
      if type INSTALL | grep "${v}" &> /dev/null; then
        error "${v} used in the install script"
        fail_check
      fi
    done
  fi

  while read l; do
    line_num=$((line_num+1))

    for v in "${bad_vars[@]}"; do
      if echo "${l}" | grep "${v}" &> /dev/null; then
        warn "${v} used without parenthesis on line ${line_num}"
        add_warning
      fi
    done

    if echo "${l}" | grep '&&' | grep -v 'cd ..' &> /dev/null; then
      warn "Unreliable use of \"&&\" on line ${line_num}"
      add_warning
    fi
  done < "${sourcepath}/pkg.sh"

  success "Check was completed"
  unset_indent

  info "Checking the changes file"
  set_indent

  if [ ! -f "${sourcepath}/changes.md" ]; then
    error "Package does not contain a changes file"
    fail_check
  fi

  if ! grep -q . "${sourcepath}/changes.md"; then
    warn "Changes file is empty"
    add_warning
  fi

  success "Check was completed"
  unset_indent
}

#################
## main script ##
#################
if [ -z "${1}" ]; then
  error "Please specify a package archive or source directory"
  exit 1
fi

if [ ! -f "${1}" ] && [ ! -d "${1}" ]; then
  error "Specified path is invalid"
  exit 1
fi

if [ -f "${1}" ]; then
  archivepath="$(realpath "${1}")"
  check_archive
elif [ -d "${1}" ]; then
  sourcepath="$(realpath "${1}")"
  check_source
fi

success_check