gh-project

#!/bin/bash

set -e

readonly GH_PROJECT_ORGANIZATION

readonly EXECUTABLES=(fzf)

usage() {
  cat <<EOF
Works with GitHub Projects from the command line.

Example:

  $ gh project list
  $ gh project list --org=acme-org
  $ gh project add 123
  $ gh project add 123 --org=acme-org
  $ gh project remove 123
  $ gh project remove 123 --org=acme-org

Environment Variables:

  GH_PROJECT_ORGANIZATION (optional)

Dependencies: ${EXECUTABLES[@]}

EOF
}

info() {
  echo "✓ $*" >&2
}

# Determine if executables are in the PATH.
check_executables() {
  for e in "${EXECUTABLES[@]}"; do
    if ! type -p "${e}" >/dev/null; then
      echo "${e} not found on the system" >&2
      return 1
    fi
  done
}

list() {
  local org
  while [[ "$#" -gt 0 ]]; do
    case "$1" in
      --org=*)
        org=${1#*=}
        ;;
      *) ;;
    esac
    shift
  done

  if [[ -n "${GH_PROJECT_ORGANIZATION}" ]]; then
    org="${GH_PROJECT_ORGANIZATION}"
  fi

  local endpoint="repos/:owner/:repo/projects"
  if [[ -n "${org}" ]]; then
    endpoint="orgs/${org}/projects"
  fi

  PAGER='cat' gh api "${endpoint}" --paginate --template '{{- range .}}{{ .name | printf "%s\n" }}{{- end -}}'
}

edit() {
  local -r cmd="${1}"
  local -r number="${2}"
  local -r flags="${*:3}"

  local project
  project="$(list "${flags[@]}" | fzf)"

  local op preposition
  case $cmd in
    'add')
      op='link'
      preposition='to'
      ;;
    'remove')
      op='unlink'
      preposition='from'
      ;;
  esac

  if gh issue view "${number}" >/dev/null 2>&1; then
    gh issue edit "${number}" "--${cmd}-project" "${project}" >/dev/null
    info "Project '${project}' has been ${op}ed ${preposition} issue #$number"
    return
  fi

  if gh pr view "${number}" >/dev/null 2>&1; then
    gh pr edit "${number}" "--${cmd}-project" "${project}" >/dev/null
    info "Project '${project}' has been ${op}ed ${preposition} pull request #$number"
    return
  fi
}

main() {
  if [[ "$#" -lt 1 ]]; then
    usage
    return 1
  fi

  if ! check_executables; then
    usage
    return 1
  fi

  local -r cmd="${1}"

  case $cmd in
    'list')
      list "${@:2}"
      ;;
    'add' | 'remove')
      edit "${cmd}" "${@:2}"
      ;;
    *)
      usage
      return 1
      ;;
  esac
}

main "$@"