subtree

#!/bin/bash

# subtree -- a utility to help working with git subtree's
# creator: inhies
# modified: aleffert
# 24 November 2013

version=1.1.2

function usage() {
	case "$1" in
	"")
		echo "Usage: subtree <add | pull | rm | list | add-all-remotes>"
		;;
	"add")
		echo "Usage: subtree add <remote name> <git url> <branch> <prefix>"
		echo "      Prefix is the directory path relative to root"
		;;
	"pull")
		echo "Usage: subtree pull <prefix | 'all'>"
		echo "      Prefix is the directory path relative to root"
		;;
	"list")
		echo "Usage: subtree list"
		echo "      Lists all known subtrees"
		;;
	"push")
		echo "Usage: subtree push <prefix | 'all'>"
		echo "      Prefix is the directory path relative to root"
		;;
	"add-all-remotes")
		echo "Usage: subtree add-remotes"
		echo "      Adds all the remotes from the subtree files"
		echo "      Prefix is the directory path relative to root"
		;;
	"rm")
		echo "Usage: subtree rm <prefix>"
		echo "      Prefix is the directory path relative to root"
		;;
	esac
	exit 1
}

# Check if we are in the root of a git repository.
isGit=$(git rev-parse --git-dir 2> /dev/null)
if [ !  -d .git ]; then
	if [ "$isGit" == "" ]; then
		# Check for a blank response, indicating a non-existant git repository.
		echo "subtree: You are not within a git repository"
		exit 1
	else
		# We are in a git repository, but not in the root of it, where we need to be.
		echo "subtree: Subtree must be ran from within the git root directory, `dirname $isGit`"
		exit 1

	fi
	exit
else
	if [ "$isGit" != ".git" ]; then
		# A .git folder exists in this directory, but git says we aren't actually in a repository.
		echo "subtree: A .git directory exists, but this doesnt seem to be a valid git repository"
		exit 1
	fi
fi;

declare -a rawMap # Global associative array to hold raw .subtrees lines

# Load the subtrees file in to the map.
function loadSubtrees(){
    if [ -f .subtrees ]
    then
        while read line
        do
            temparray=( $line )
            rawMap[${temparray[0]}]=$line	
        done < "./.subtrees"
    fi
}

function add() {
	# Add the remote and return if there is an error
	echo git remote add -f $1 $2 
	git remote add -f $1 $2 
	if [ "$?" -ne "0" ]; then
		return
	fi
	echo git subtree add --prefix $4 $1 $3 --squash
	git subtree add --prefix $4 $1 $3 --squash
	# If there was an error adding the subtree, remove the remote we just added
	if [ "$?" -ne "0" ]; then
		git remote rm $1
		return
	fi
	echo "$1 $2 $3 $4" >> .subtrees
	git add .subtrees
	git commit -m "Pull .subtrees for $1"
}

# name prefix
function remove() {
	echo "subtree: Removing remote $1"
	git remote rm $1
	if [ "$?" -ne "0" ]; then
		echo "subtree: Error removing remote $1"
		return
	fi

	echo "subtree: Removing files from $4"
	rm -rf ./$4
	if [ "$?" -ne "0" ]; then
		echo "subtree: Error removing files from $4"
        git remote add -f $1 $2
		return
	fi

	git rm -r $4
	if [ "$?" -ne "0" ]; then
		echo "subtree: Error removing files '$4' from git"
        git remote add -f $1 $2
		return
	fi

	sed -i ".bak" "/^$1/d" .subtrees
    rm .subtrees.bak
	if [ "$?" -ne "0" ]; then
		echo "subtree: Error removing subtree $1 from .subtrees file"
        git remote add -f $1 $2
		return
	fi

	git add .subtrees
	git commit -m "Removed subtree $1 from '$4'"
	if [ "$?" -ne "0" ]; then
		echo "subtree: Error commiting removal of subtree $1"
		return
	fi
}

function pull(){
	git fetch $1 $3
	if [ "$?" -ne "0" ]; then
		return
	fi
	git subtree pull --prefix $4 $1 $3 --squash
}

function push(){
	git subtree push --prefix $4 $1 $3 --squash
}

function add-remote() {
    git remote add -f $1 $2
    if [ "$?" -ne "0" ]; then
        echo "Skipping $1"
    fi
}

case "$1" in
"-v" | "--version")
	echo "subtree version $version"
	exit 0
	;;

"pull")
	loadSubtrees
	case "$2" in 
	"all")
		for v in "${rawMap[@]}"; do 
			pull $v
			if [ "$?" -ne "0" ]; then
				echo "subtree: error updating subtree:\n\t$v"
				exit 1
			fi
		done
		;;

	*)
		if [ "$2" == '' ]; then
			usage "pull"
		fi
		if [ "${rawMap[$2]}" == "" ] ; then 
			echo "subtree: $2 is not a subtree item. Check .subtrees file"
			exit 1
		fi
		pull ${rawMap[$2]}
		if [ "$?" -ne "0" ]; then
			echo "subtree: error updating subtree $2"
			exit 1
		fi
		;;
	esac
	;;
"push")
	loadSubtrees
	case "$2" in 
	"all")
		for v in "${rawMap[@]}"; do 
			push $v
			if [ "$?" -ne "0" ]; then
				echo "subtree: error updating subtree:\n\t$v"
				exit 1
			fi
		done
		;;

	*)
		if [ "$2" == '' ]; then
			usage "push"
		fi
		if [ "${rawMap[$2]}" == "" ] ; then 
			echo "subtree: $2 is not a subtree item. Check .subtrees file"
			exit 1
		fi
		push ${rawMap[$2]}
		if [ "$?" -ne "0" ]; then
			echo "subtree: error updating subtree $2"
			exit 1
		fi
		;;
	esac
	;;
"add-all-remotes")
	loadSubtrees
    for v in "${rawMap[@]}"; do 
        add-remote $v
        if [ "$?" -ne "0" ]; then
            echo "subtree: error adding remote for subtree :\n\t$v"
            exit 1
        fi
    done
    ;;
"list")
    loadSubtrees
    for v in "${rawMap[@]}"; do 
        echo $v
    done
     ;;
"add")
	loadSubtrees
	if [ "${rawMap[$2]}" != "" ] ; then 
		echo "subtree: $2 already exists"
		exit 1
	fi

	if [ "$5" == '' ]; then
		usage "add"
	fi

	add $2 $3 $4 $5
	if [ "$?" -ne "0" ]; then
		echo "subtree: error adding subtree $2"
		exit 1
	fi
	;;

"rm" | "remove")
	if [ "$2" == '' ]; then
		usage "rm"
	fi

	loadSubtrees
	if [ "${rawMap[$2]}" == "" ] ; then 
		echo "subtree: $2 is not a subtree item. Check .subtrees file"
		exit 1
	fi

	remove ${rawMap[$2]}
	if [ "$?" -ne "0" ]; then
		echo "subtree: error removing subtree $2"
		exit 1
	fi
	;;
*)
	usage
	;;
esac