#!/usr/bin/env bash
# shellcheck disable=SC2128

# Shows the usage
function usage() {
  cat << EOS
Usage:
  git local-prune [-m <max-dir-depth>] [-f] [-F] [-r] [-F] [-L] [-h]

  -h      - Display this help screen
  -m      - Specify the depth of recursive directory search
  -f      - Fetch the latest commits beforehand
  -r      - Generate a file with the report
  -F      - Force recursion up to specified depth
  -L      - Toggle inclusion of symbolic links in recursive directory search

Examples:
  git local-prune -m 3
EOS
}

# Sets up the colored output
function colored() {
  RED=$(tput setaf 1)
  GREEN=$(tput setaf 2)
  YELLOW=$(tput setaf 3)
  BLUE=$(tput setaf 4)
  BOLD=$(tput bold)
  UNDERLINE=$(tput smul)
  NORMAL=$(tput sgr0)

  GIT_PRETTY_DATE="%cd"
  if [[ ${option_R:=} ]]; then
    GIT_PRETTY_DATE="%ad"
  fi

  GIT_PRETTY_FORMAT="%Cred%h%Creset - %s %Cgreen($GIT_PRETTY_DATE) %C(bold blue)<%an>%Creset"
  COLOR=always

  if [[ ${option_g:=} ]]; then
    GIT_PRETTY_FORMAT="$GIT_PRETTY_FORMAT %C(yellow)gpg: %G?%Creset"
  fi
}

# Sets up the uncolored output
function uncolored() {
  # shellcheck disable=SC2034
  RED=""
  GREEN=""
  YELLOW=""
  # shellcheck disable=SC2034
  BLUE=""
  BOLD=""
  UNDERLINE=""
  NORMAL=""

  GIT_PRETTY_DATE="%cd"
  if [[ $option_R ]]; then
    GIT_PRETTY_DATE="%ad"
  fi

  GIT_PRETTY_FORMAT="%h - %s ($GIT_PRETTY_DATE) <%an>"
  COLOR=never

  if [[ $option_g ]]; then
    GIT_PRETTY_FORMAT="$GIT_PRETTY_FORMAT gpg: %G?\n"
  else
    GIT_PRETTY_FORMAT="$GIT_PRETTY_FORMAT \n"
  fi
}

function writeFile() {
  echo -e "$1" >> "${REPORT_FILE_PATH}"
}

function runLocalPrune() {
  # Fetch the latest commits, if required
  if [[ ${option_f:=} ]]; then
    echo "${BOLD}${GREEN}Fetching commits in ${YELLOW}${UNDERLINE}${BOLD}${BASENAME}${NORMAL}"
    git fetch --all --prune > /dev/null 2>&1
  fi

  {
    # shellcheck disable=SC2086
    GITOUT=$(eval ${GIT_LOCAL_PRUNE_COMMAND} 2> /dev/null)
  } || {
    GITOUT=""
  }

  # If `r` option was given then no output, just write the report
  if [[ -n ${option_r:=} ]]; then
    if [[ -n "$GITOUT" ]]; then
      writeFile "${CUR_DIR}\n $GITOUT"
    fi
  else
    ## Only output if there is some activity
    if [[ -n "$GITOUT" ]]; then
      echo "${BOLD}${UNDERLINE}${YELLOW}$CUR_DIR${NORMAL}"
      echo "$GITOUT"
    else
      echo "${BOLD}${UNDERLINE}${YELLOW}$CUR_DIR${NORMAL}"
      echo "${YELLOW}No local branch gone on remote!${NORMAL}"
    fi
  fi
}

while getopts "hfm:LrF" opt; do
  case $opt in
    h | f | m | L | r | F)
      declare "option_$opt=${OPTARG:-0}"
      ;;
    \?)
      echo >&2 "Use 'git local-prune -h' to see usage info"
      exit 1
      ;;
  esac
done

shift $((OPTIND - 1))

if [[ $# -gt 0 ]]; then
  echo >&2 "Invalid arguments: $*"
  echo >&2 "Use 'git locale-prune -h' to see usage info"
  exit 1
fi

# Main script
if [[ ${option_h:=} ]]; then
  usage
  exit 0
fi

# Use colors, but only if connected to a terminal, and that terminal supports them.
if [[ -t 1 ]] && [[ -n "$TERM" ]] && command -v tput &> /dev/null && tput colors &> /dev/null; then
  ncolors=$(tput colors)
  if [[ -n "$ncolors" ]] && [[ "$ncolors" -ge 8 ]] && [[ -z "$option_r" ]]; then
    colored
  else
    uncolored
  fi
else
  uncolored
fi

## Set the necessary variables for local-prune
MAXDEPTH=2
INCLUDE_LINKS=
RAN_FROM_DIR=$(pwd)
REPORT_FILE_PATH="${RAN_FROM_DIR}/git-local-prune-report.txt"

# If report is to be generated, remove the existing report file if any
if [[ -n $option_r ]]; then
  rm -rf "${REPORT_FILE_PATH}"
fi

if [[ ${option_m:=} ]]; then
  MAXDEPTH="$((${option_m:=} + 1))"
fi

if [[ ${option_L:=} ]]; then
  INCLUDE_LINKS="-L"
fi

# For when the command has been run in a non-repo directory
if [[ ${option_F:=} || ! -d ".git" || -f ".git" ]]; then
  BASE_DIR=$(pwd)
  # Set delimiter to newline for the loop
  IFS=$'\n'

  if [[ -f ".git-local-prune-whitelist" ]]; then
    SEARCH_PATH=$(cat .git-local-prune-whitelist)
  else
    SEARCH_PATH=.
  fi

  # Recursively search for git repositories
  PROJECT_DIRS=$(find ${INCLUDE_LINKS} ${SEARCH_PATH} -maxdepth ${MAXDEPTH} -mindepth 0 -name .git)
elif [[ -f ".git" || -d ".git" ]]; then
  PROJECT_DIRS=("$(pwd)/.git")
fi

# if project directories is still empty
# we might be sitting inside a git repo
if [[ -z ${PROJECT_DIRS} ]]; then
  ROOT_DIR_COMMAND="git rev-parse --show-toplevel"
  PROJECT_ROOT=$(eval "${ROOT_DIR_COMMAND}" 2> /dev/null)

  if [[ -z ${PROJECT_ROOT} ]]; then
    echo "${YELLOW}You must be inside a git repository!${NORMAL}"
    exit 0
  fi

  PROJECT_DIRS=("${PROJECT_ROOT}/.git")
fi

# Foreach of the project directories, run the local-prune
IFS=$'\n'
for DIR in ${PROJECT_DIRS}; do
  PROJECT_DIR=$(dirname "$DIR")
  cd "$PROJECT_DIR" || exit
  CUR_DIR=$(pwd)
  BASENAME=$(basename "$CUR_DIR")

  # continue if not a git directory
  if [[ ! -d ".git" || -f ".git" ]]; then
    cd "${BASE_DIR}" || exit
    continue
  fi

  GIT_LOCAL_PRUNE_COMMAND="git --no-pager branch --v \
    | grep \"\\[gone\\]\" \
    | awk '{print \$1}'
    | xargs git branch -D"

  runLocalPrune

  cd "${BASE_DIR}" || exit
done
unset IFS