#!/bin/sh

## SPDX-FileCopyrightText: 2023 - 2025 Benjamin Grande M. S. <ben.grande.b@gmail.com>
##
## SPDX-License-Identifier: AGPL-3.0-or-later

set -eu

if command -v delta >/dev/null; then
  exec delta -- "${@}"
else
  : "${DIFF_HIGHLIGHT_SOURCE:=/usr/share/doc/git/contrib/diff-highlight}"
  : "${DIFF_HIGHLIGHT_EXEC:=/usr/share/git-core/contrib/diff-highlight}"

  git_less(){
    exec less -RS -- "${@}"
  }

  ## Debian.
  if command -v perl >/dev/null &&
    test -f "${DIFF_HIGHLIGHT_SOURCE}/DiffHighlight.pm" &&
    test -f "${DIFF_HIGHLIGHT_SOURCE}/diff-highlight.perl"
  then
    exec perl -I "${DIFF_HIGHLIGHT_SOURCE}" -MDiffHighlight -- \
      "${DIFF_HIGHLIGHT_SOURCE}/diff-highlight.perl" | git_less
    exit
  ## Fedora.
  elif command -v perl >/dev/null && test -f "${DIFF_HIGHLIGHT_EXEC}"
  then
    exec "${DIFF_HIGHLIGHT_EXEC}" | git_less
    exit
  fi

  git_less "${@}"
fi