#!/bin/bash

# when executed via the OS X Finder, the working directory will likely not be
# correct. this fixes that (working directory = directory this script is in)
cd "$(dirname "$0")"



#----- VARIABLES + CONFIG ------------------------------------------------------

# shouldn't need to touch any of these 4 under normal circumstances ...
#
# NOTE: PROJECT_NAME is set assuming that the parent directory to the one that
#       this script is contained in has a name that is suitable to be used for
#       this "project name" value.
#
#       e.g. it assumes that this script is located at something like:
#                /home/user/projects/PROJECT_NAME/marmalade/mkb_generate
#                                    ^^^^^^^^^^^^
#            and so PROJECT_NAME will be set accordingly.
#
PROJECT_NAME=$(pushd . > /dev/null; cd ..; basename $(pwd); popd > /dev/null)
MKB_TEMPLATE=./mkb_template.txt
MKB_OUTPUT_FILE=./$PROJECT_NAME.mkb
TEMP_SOURCE_DIR_LIST_FILE=./temp_sources_list

# list of directories (relative to this directory) to include in the MKB's
# source directory listing. any subdirectories of the directories listed will
# be included automatically
DIR_SOURCES=( ../lib ../src )

# list of directories that are contained in one of the directories listed in
# DIR_SOURCES (e.g. a subdirectory somewhere in one of them) to be excluded
# from the MKB's source directory listing. any subdirectories under these
# excluded directories will also be excluded
DIR_SOURCES_EXCLUDE=( ../lib/glew ../lib/sdl-osx )

#-------------------------------------------------------------------------------



#----- FUNCTIONS ---------------------------------------------------------------

function isSourceDirExcluded()
{
	check_dir=$1
	for i in "${DIR_SOURCES_EXCLUDE[@]}"
	do
		# check passed directory against each directory listed in the excludes list
		# this just makes sure the beginning is the same (so sub dirs, etc. will still match)
		if [[ $check_dir = $i* ]]; then
			return 0
		fi
	done

	return 1
}

function hasSources()
{
	check_dir=$1

	# don't bother checking if the directory has sources if this directory
	# is to be excluded...
	if isSourceDirExcluded $check_dir; then
		return 1
	else
		# it's not excluded, now we can check for source files
		if [ `find $check_dir/*.cpp $check_dir/*.c $check_dir/*.h -type f -mindepth 0 2> /dev/null | wc -l` != 0 ]; then
			return 0
		else
			return 1
		fi
	fi
}

function writeTempListOfSourceDirectories()
{
	# for each of the root source directories specified ...
	for i in "${DIR_SOURCES[@]}"
	do
		# ... and then for each sub dir in this root source directory ...
		find $i -type d | while read -r dir
		do
			# ... check if this sub dir has cpp/c/h files in it ...
			if hasSources $dir; then
				# ... and if so, write a line for it out to the temp file
				# (this written line matches syntax appropriate for an MKB "files" section
				# directory wildcard)
				dir_name=${dir#../}                # strip "../" from the beginning
				echo "($dir) [$dir_name] '*.*'" >> $TEMP_SOURCE_DIR_LIST_FILE
			fi
		done
	done
}

function writeOutMkb()
{
	# this keeps tab characters in the lines we read
	oldifs="$IFS"
	IFS=""

	# read each line from the MKB template and copy it to the output file
	cat $MKB_TEMPLATE | while read template_line; do

		############################################
		# look for template placeholders
		# (right now, we assume the template placeholders occur on a line all by themselves)

		# source directory list
		if [[ $template_line = *%%SOURCE_FILES%%* ]]; then
			# read the previous generated temp source dir list file and copy it
			# into the mkb output line by line as-is
			cat $TEMP_SOURCE_DIR_LIST_FILE | while read source_dir_list_line; do
				echo "$source_dir_list_line" >> $MKB_OUTPUT_FILE
			done

		############################################

		# nothing special on this line, just copy it to the output as-is...
		else
			echo "$template_line" >> $MKB_OUTPUT_FILE
		fi
	done

	# reset this when we're done
	IFS="$oldifs"
}

#-------------------------------------------------------------------------------



# ----- CONFIG AND FILE STATE SANITY CHECKING ----------------------------------

# make sure some source directories were specified above
if [ ${#DIR_SOURCES[@]} == 0 ]; then
	echo "ERROR: No source directories specified."
	exit 1
fi

# make sure each source directory exists
for source_dir in "${DIR_SOURCES[@]}"
do
	if [ ! -d $source_dir ]; then
		echo "ERROR: Source directory \"$source_dir\" does not exist."
		exit 1
	fi
done

# make sure each excluded source directory exists
for excluded_source_dir in "${DIR_SOURCES_EXCLUDE[@]}"
do
	if [ ! -d $excluded_source_dir ]; then
		echo "ERROR: Excluded source directory \"$excluded_source_dir\" does not exist."
		exit 1
	fi
done

# make sure MKB input template file exists
if [ ! -f $MKB_TEMPLATE ]; then
	echo "ERROR: MKB template file does not exist."
	exit 1
fi

# if the temp source dir list file exists, delete it
if [ -f $TEMP_SOURCE_DIR_LIST_FILE ]; then 
	rm $TEMP_SOURCE_DIR_LIST_FILE
fi

# if the output MKB file exists, delete it
if [ -f $MKB_OUTPUT_FILE ]; then
	rm $MKB_OUTPUT_FILE
fi



#----- MAIN SCRIPT PROCESSING --------------------------------------------------

writeTempListOfSourceDirectories

if [ ! -f $TEMP_SOURCE_DIR_LIST_FILE ]; then
	echo 'ERROR: Problem occurred while scanning for source file directories.'
	exit 1
fi

writeOutMkb

if [ ! -f $MKB_OUTPUT_FILE ]; then
	echo 'ERROR: Problem occurred while writing out new MKB file.'
	exit 1
fi

#-------------------------------------------------------------------------------



#----- CLEANUP -----------------------------------------------------------------

# if the temp source dir list file exists, delete it
if [ -f $TEMP_SOURCE_DIR_LIST_FILE ]; then 
	rm $TEMP_SOURCE_DIR_LIST_FILE
fi

#-------------------------------------------------------------------------------