# This file provides the following direnv extensions:
# * ensure_all_documented
# * ensure_all_set
# It assumes .envrc lists all environment variables *required* by a project,
# by exporting them set equal to an empty string:
#     export MYVAR=
# or, to the default value:
#     export MYVAR=some-default
# .envrc.private (which should be excluded from source control) supplies the values
# for required variables.

# Usage:
# 1. In `.envrc`, document all exports:
#
#     # MYVAR: a value I want to set
#     export MYVAR=
#     # OTHERVAR: (optional) a value I might want to set
#     export OTHERVAR=
#
#     source_env .envrc.private
#
# 2. In `.envrc.private`, set all required values:
#
#     export MYVAR=foo
#
# 3. At the end of `.envrc`, invoke the extensions (after checing they are available):
#
#     if has ensure_all_documented; then
#       ensure_all_documented
#     else
#       echo "No ensure_all_documented function found, skipping documentation check"
#     fi
#
#     if has ensure_all_set; then
#       ensure_all_set
#     else
#       echo "No ensure_all_set function found, skipping environment variable check"
#     fi

__direnv_print_error() (
  local RED="\e[1;31m"
  local DEFAULT="\e[0m"
  echo -e "${RED}$1${DEFAULT}"
)

all_exports() (
  # Find lines with exports of environment variables,
  # collect the names of the environment variables.
  # To get exported environment variables as an array
  # do this:
  #     local exports=($(all_exports))
  grep -Po '(?<=^export )[A-Z0-9_]+(?==)' .envrc
)

# Ensure that all exports from .envrc are documented,
# unless they are marked as (optional).
# A comment should be as follows:
# '# VARIABLE: documentation'
ensure_all_documented() (
  local exports=($(all_exports))
  for (( i=0; i<${#exports[@]}; i++ ))
  do
    local export=${exports[$i]}
    grep -P "^# $export:" .envrc >/dev/null || __direnv_print_error "direnv: export $export does not have a comment"
  done
)

ensure_all_set() (
  local exports=($(all_exports))
  for (( i=0; i<${#exports[@]}; i++ ))
  do
    local export=${exports[$i]}
    # Skip optional exports
    if grep -P "^# $export: \(optional\)" .envrc >/dev/null; then
      continue
    fi
    if [ -z ${!export} ]; then
      __direnv_print_error "direnv: export $export is unset. Either set it in .envrc.private or mark it as optional by adding a comment '# $export: (optional) ...'"
    fi
  done
)