generate

#!/bin/sh
#############################################################
#
# canhaz generator driver
#
# This script drives the generation of files by setting up
# the general canhaz environment, paths, etc., loading the
# config, and then executing the setup, generator, and
# teardown scripts
#
#############################################################

ME=`basename $0`
USAGE="Usage: $ME [--force] module_path [generators]"
VERSION="v1.0"

MY_DIR="$HOME/.canhaz"
MY_BIN_DIR="$MY_DIR/bin"
GEN_OBJECT="$MY_BIN_DIR/gen-object"

#
# Print a message.  Generator plugins should use this instead of echo
#
function msg {
	echo "$@"
}

#
# Print an error to stderr
#
function err {
	echo "ERROR: $@" >&2
}

#
# Print an error and exit with the supplied exit value, or 1 if no
# exit value specified
#
function fail {
	err "$1"
	exit $2||1
}

function load {
	local FILE="${GEN_BASE_DIR}/$1"
	# echo "Loading $FILE"

	# If the requested file exists, execute it
	# If it doesn't, and error message was supplied, print it
	if [[ -f "$FILE" ]]; then
		. "$FILE"
	elif [[ "$2" != "" ]]; then
		err "$2"
	fi
}


#
# Function to generate content from a template
# Params:
#  $1 - template file
#
function template {
	perl -p -e 's/[\$]\{([A-Za-z_][A-Za-z0-9_]+)\}/defined $ENV{$1} ? $ENV{$1} : $&/eg' "$1"
}

export -f msg err fail load template

#
# Find config file.  This will try any locations listed first, then search upward,
# and finally use the default config if no other config has been found.
#
function find_config {
	local DEFAULT_CONFIG="$MY_DIR/config"

	local c
	for c in "$@"
	do
		if [[ -f "$c" ]]; then
			CONFIG="$c"
			return 1
		fi
	done
	
	# Search upward for config
	local FILE=".canhaz/config"
	CONFIG=`find_ancestor $FILE`
	
	if [[ ! -f "$CONFIG" ]]; then
		CONFIG="$DEFAULT_CONFIG"
	fi
}

#
# Searches upward in the dir hierarchy to find a file or dir with a particular name
# Params:
#  $1 - dir or file name to find
#  $2 - (optional) directory in which to start searching.  Search will proceed upward
#       from here.  If not specified, the current working dir will be used.
#
function find_ancestor {
	# Search upward for config
	local FILE="$1"
	local DIR=${2:-$PWD}

	while [[ "$DIR" != '/' ]]; do
	    if [[ -e "$DIR/$FILE" ]]; then
			echo "$DIR/$FILE"
			return 1
	    else
	        DIR=`dirname $DIR`
	    fi
	done
}

# Defaults
FORCE=false

# Find config file.
find_config "./.canhaz/config"
export CONFIG_DIR=`dirname "$CONFIG"`
export CONFIG_PARENT_DIR=`dirname "$CONFIG_DIR"`

# Parse command line options.
for arg in "$@"
do
	case "$arg" in
		-h|--help)
			msg "$USAGE"
			exit 0
			;;
		-v|--version)
			msg "$ME $VERSION"
			exit 0
			;;
		-f|--force)
			FORCE=true
			shift
			;;
		-c|--config)
			shift
			CONFIG=$1
			shift
			;;
	esac
done

BASE_DIR=`pwd`

# We want at least one non-option argument.
# Remove this block if you don't need it.
if [ $# -eq 0 ]; then
	msg "$USAGE"
	exit 1
fi

# Load config
if [[ ! -f "$CONFIG" ]]; then
	fail "Can't read config: $CONFIG" 1
fi

. "$MY_DIR/config"

# Figure out what type of thing we're generating
USER_OBJECT_TYPE=${1//:/\/}

if [[ -d "$GEN_BASE_DIR/$USER_OBJECT_TYPE" ]]; then
	OBJECT_TYPE=$USER_OBJECT_TYPE
	shift
else
	OBJECT_TYPE="${DEFAULT_TYPE//:/\/}"
fi

# Get the path/name of the thing
MODULE_PATH="$1"
shift

# Command line generator list takes precedent over config
if [[ "$*" != "" ]]; then
	USER_GENERATORS="$*"
fi

MODULE=`basename "$MODULE_PATH"`
MODULE_BASE=`dirname "$MODULE_PATH"`

CANHAZ_DIR="$MY_DIR"

# Export vars that should be available to templates
export CANHAZ_DIR ME VERSION PHP MY_DIR MY_BIN_DIR GEN_BASE_DIR MODULE MODULE_BASE BASE_DIR TEST_DIR TEMPLATE_DIR FORCE COPYRIGHT

# Run the general setup, if it exists
load "setup"

sh "$GEN_OBJECT" "$OBJECT_TYPE" $USER_GENERATORS

# Run the general teardown, if it exists
load "teardown"

msg "Done"