#!/bin/bash

function error {

    echo "ERROR: $1"

    exit 1

}

if [ -z "$1" ]; then

   error "No source build tree specified"

fi

SRCDIR=$1

if [ ! -d "$SRCDIR" ]; then 

    error "Source directory does not exist: $SRCDIR"

fi

if [ -z "$2" ]; then

    DSTDIR=build

else 

    DSTDIR=$2

fi

if [ ! -d "$DSTDIR" ]; then 

    error "Destination directory does not exist: $DSTDIR"

fi

pushd "$SRCDIR"

repos=$(find ./ -name .hg -prune)

popd

set -e

for repo_store in $repos; do

    repo=$(dirname $repo_store)

    if [ -d $DSTDIR/$repo ]; then

    	if [ -f $DSTDIR/$repo/.hg/sharedpath ]; then

    	    echo "Repository $repo already exists and shared"

    	else 

    		echo "Directory $repo already exists."

    		echo -n "Move aside and share (y/N/Ctrl-C)? "

    		read yesOrNo

    		if [ $yesOrNo == 'y' ]; then

    			if ! mv $DSTDIR/$repo $DSTDIR/${repo}_$(date +%Y-%M-%d); then

                    error "Failed to move $DSTDIR/$repo aside to $DSTDIR/${repo}_$(date +%Y-%M-%d)"

                fi

    		fi

    	fi

    fi

    if [ -d $DSTDIR/$repo ]; then

    	if [ ! -d $DSTDIR/$repo/.hg/sharedpath ]; then

            echo "Not sharing $repo - already exists"

    	fi

    else 

        echo "Sharing $repo..."

	if [ ! -d "$DSTDIR/$(dirname $repo)" ]; then 

	    mkdir -p "$DSTDIR/$(dirname $repo)"

	fi

	hg share -U -B "$SRCDIR/$repo" "$DSTDIR/$repo"

	repo_rev=$(hg --cwd "$SRCDIR/$repo" log -r . --template "{node}")

	echo "Updating to $repo_rev"

	hg --cwd "$DSTDIR/$repo" update -r $repo_rev

    fi

    echo 

done