#!/bin/bash

####################
# Helper functions #
####################

SELF="$0"

function error {
	tput setaf 9
	tput bold
	printf "%s: ERROR: " "$0"
	printf "$@"
	tput sgr0
	exit 1
}

function debug {
	if [ "$DEBUG" -ne 1 ]; then
		return
	fi

	tput setaf 12
	printf "[DEBUG] "
	printf "$@"
	tput sgr0
}

function check_file {
	[ -e "$1" ] || error "'%s' doesn't exist\n" "$1"
	[ -d "$1" ] && error "'%s' is a directory, not a file\n" "$1"
	[ -f "$1" ] || error "'%s' exists but isn't a file\n" "$1"
}

function check_dir {
	[ -e "$1" ] || error "'%s' doesn't exist\n" "$1"
	[ -f "$1" ] && error "'%s' is a file, not a directory\n" "$1"
	[ -d "$1" ] || error "'%s' exists but isn't a directory\n" "$1"
}

function ensure_link {
	if [ -L "$2" ]; then
		debug "ensure_link: '%s' already exists\n" "$2"
		if [ `readlink "$2"` == "$1" ]; then
			return
		fi

		debug "ensure_link: ...and points at '%s' instead of '%s'\n" `readlink "$2"` "$1"
		unlink "$2" || error "couldn't unlink '%s'\n" "$2"
	fi

	mkdir -p `dirname "$2"` || error
	ln -s "$1" "$2" || error "linking failed\n"
	debug "ensure_link: linked '%s' -> '%s'\n" "$2" "$1"
}

#################
# Configuration #
#################

# Load the script configuration and set some defaults.
source run-instance.local.sh || error "missing config\n"
[ -z "$PREFIX" ] && error "PREFIX is not set\n"

# fs_basepath, fs_overpath, fs_homepath and fs_game.
true ${COMMON:="$PREFIX/common"}
true ${OVER_PREFIX:="$PREFIX/over@"}
true ${HOME_PREFIX:="$PREFIX/home@"}
true ${FS_GAME:="slacker"}

# Config directory: as seen by tremded's vfs and the absolute path, respectively. 
true ${CONFIG_LOCAL:="config"}
true ${CONFIG_GLOBAL:="$PREFIX/$CONFIG_LOCAL"}

# Executables.
true ${GDB_WRAPPER:="$PREFIX/bin/gdb-wrapper2.sh"}
true ${TREMDED_PREFIX:="$PREFIX/bin/tremded@"}

# Debugging
true ${DEBUG:=1}
true ${NO_DEBUGGER:=0}

if [ "$NO_DEBUGGER" -ne 0 ]; then
	GDB_WRAPPER="exec"
fi

###################
# The entry point #
###################

# Check the argument.
[ -z "$1" ] && error "instance name is missing\nusage: %s [INSTANCE]\n" "$SELF"

# Figure out all the instance-specific paths.
I="$1"
TREMDED="$TREMDED_PREFIX$I"
OVER="$OVER_PREFIX$I"
HOME="$HOME_PREFIX$I"
CONFIG_COMMON="$CONFIG_GLOBAL/common.cfg"
CONFIG_INST="$CONFIG_GLOBAL/$I.cfg"

# Do some integrity checks.
[ "$NO_DEBUGGER" -eq 0 ] && check_file "$GDB_WRAPPER"
check_file   "$TREMDED"
check_dir    "$COMMON"
check_file   "$COMMON/base/data-1.1.0.pk3"
check_dir    "$OVER"
check_dir    "$OVER/$FS_GAME"
check_file   "$OVER/$FS_GAME/game.so" 
check_dir    "$HOME"
check_dir    "$HOME/$FS_GAME"
check_file   "$CONFIG_COMMON"
check_file   "$CONFIG_INST"
ensure_link  "$CONFIG_GLOBAL" "$HOME/$FS_GAME/$CONFIG_LOCAL"

# Server configuration is done by overwiting the autogen.
cat "$CONFIG_COMMON" "$CONFIG_INST" > "$HOME/$FS_GAME/autogen_server.cfg" \
	|| error "couldn't overwrite the autogen\n"

# cd to HOME (that's where cores will appear) and start the server.
cd "$HOME" || error "cannot chdir to %s\n" "$HOME"
"$GDB_WRAPPER" "$TREMDED" \
	+set fs_basepath "$COMMON" \
	+set fs_overpath "$OVER" \
	+set fs_homepath "$HOME" \
	+set fs_game "$FS_GAME" \
	+set com_pipefile "pipe" \
	+set dedicated 2 \
	+map "atcs" \
	+nocurses \
	"$@" || error "couldn't start the server\n"