#!/usr/bin/env bash
#
# Cat a file(s) by filename from a GIT repository.
# Copyright (c) John Ellson, 2005
#
# Cat a file of a given filename in a given revision (or in the current
# one) to stdout.
#
# OPTIONS
# -------
# -r TREE_ID:: Look for file in the given revision or tree
#	ID of the revision or tree where to look for the file, instead of
#	HEAD.

# The tale of birth:
# Initiated from a request from:		    erg@research.att.com
#   for an equivalent to "cvs co -p <filename>"
# Question posted with really bad initial solution: ellson@research.att.com
# Suggestions offered by:			    Johannes.Schindelin@gmx.de
#						    rene.scharfe@lsrfire.ath.cx
# This solution based on posting from:		    torvalds@osdl.org
# Polish and test by:				    ellson@research.att.com

USAGE="cg-admin-cat [-r TREE_ID] FILE..."

. "${COGITO_LIB}"cg-Xlib || exit 1

rev=HEAD
while optparse; do
	if optparse -r=; then
		rev="$OPTARG"
	else
		optfail
	fi
done

[ ${#ARGS[*]} -ge 1 ] || usage

id=$(cg-object-id -t "$rev") || exit 1

git-ls-tree "$id" "${ARGS[@]}" |
	while read -r mode type sha name
	do
		case "$type" in
		blob)
			git-cat-file blob "$sha"
			;;
		tree)
			git-ls-tree "$sha"
			;;
		*)
			exit 1
			;;
		esac
	done