#!/usr/bin/env sh
###########################################################################
## Original @ https://github.com/fkalis/bash-json-parser                 ##
## Modifications by Wizardry and Steamworks:                             ##
##   * dash compatibility                                                ##
###########################################################################
## conversion from bash with the following changes:                      ##
##   * parse "" "" <<< "${INPUT}" -> echo "${INPUT}" | parse "" ""       ##
##   * == -> =                                                           ##
##   * read -r -s -n 1 c -> readc c                                      ##
###########################################################################

json_readc() {
	if [ -t 0 ]; then
		saved_tty_settings=$(stty -g);
		stty -icanon -echo min 1 time 0;
	fi;
	c=$(dd bs=1 count=1 conv=noerror,sync 2>/dev/null);
	if [ -t 0 ]; then
		stty "$saved_tty_settings";
	fi;
};
json_set_entry() {
	echo "$1=$2";
};
json_parse_array() {
	local current_path="${1:+$1.}$2";
	local current_scope="root";
	local current_index=0;
	while [ "$chars_read" -lt "$INPUT_LENGTH" ]; do
		[ "$preserve_current_char" = "0" ] && chars_read=$((chars_read + 1)) && json_readc c;
		preserve_current_char=0;
		c=${c:-' '};
		case "$current_scope" in
		"root") 
			case "$c" in
			'{')
                json_parse_object "$current_path" "$current_index";
				current_scope="entry_separator";
				;;
			']')
				return;
				;;
			[\"tfTF\-0-9])
				preserve_current_char=1;
				json_parse_value "$current_path" "$current_index";
				preserve_current_char=1;
				current_scope="entry_separator";
				;;
			esac
			;;
		"entry_separator")
			[ "$c" = "," ] && current_index=$((current_index + 1)) && current_scope="root";
			[ "$c" = "]" ] && return;
			;;
		esac
	done
};
json_parse_value() {
	local current_path="${1:+$1.}$2";
	local current_scope="root";
	while [ "$chars_read" -lt "$INPUT_LENGTH" ]; do
		[ "$preserve_current_char" = "0" ] && chars_read=$((chars_read + 1)) && json_readc c;
		preserve_current_char=0;
		c=${c:-' '};
		case "$current_scope" in
		"root") 
			case "$c" in
			'"') 
				current_scope="string";
				current_varvalue="";
				;;
			[\-0-9]) 
				current_scope="number";
				current_varvalue="$c";
				;;
			[tfTF]) 
				current_scope="boolean";
				current_varvalue="$c";
				;;
			"[") 
				json_parse_array "" "$current_path";
				return;
				;;
			"{") 
				json_parse_object "" "$current_path";
				return;
				;;
			esac
			;;
		"string") 
			case "$c" in
			'"') 
				[ "$current_escaping" = "0" ] && json_set_entry "$current_path" "$current_varvalue" && return;
				[ "$current_escaping" = "1" ] && current_varvalue="$current_varvalue$c" && current_escaping=0;
				;;
			'\') 
				[ "$current_escaping" = "1" ] && current_varvalue="$current_varvalue$c";
				current_escaping=$((1 - current_escaping));
				;;
			*) 
				current_escaping=0;
				current_varvalue="$current_varvalue$c";
				;;
			esac
			;;
		"number") 
			case "$c" in
			[,\]}]) 
				json_set_entry "$current_path" "$current_varvalue";
				preserve_current_char=1;
				return
				;;
			[\-0-9.]) 
				current_varvalue="$current_varvalue$c";
				;;
				
			esac
			;;
		"boolean") 
			case "$c" in
			[,\]}]) 
				json_set_entry "$current_path" "$current_varvalue";
				preserve_current_char=1;
				return;
				;;
			[a-zA-Z]) 
				current_varvalue="$current_varvalue$c";
				;;
			esac
			;;
		esac
	done
};
json_parse_object() {
	local current_path="${1:+$1.}$2";
	local current_scope="root";
	while [ "$chars_read" -lt "$INPUT_LENGTH" ]; do
		[ "$preserve_current_char" = "0" ] && chars_read=$((chars_read + 1)) && json_readc c;
		preserve_current_char=0;
		c=${c:-' '};
		case "$current_scope" in
		"root") 
			[ "$c" = "}" ] && return;
			[ "$c" = "\"" ] && current_scope="varname" && current_varname="" && current_escaping=0;
			;;
		"varname")
			case "$c" in
			'"') 
				[ "$current_escaping" = "0" ] && current_scope="key_value_separator";
				[ "$current_escaping" = "1" ] && current_varname="$current_varname$c" && current_escaping=0;
				;;
			'\') 
				current_escaping=$((1 - current_escaping));
				current_varname="$current_varname$c";
				;;
			*) 
				current_escaping=0;
				current_varname="$current_varname$c";
				;;
			esac
			;;
		"key_value_separator")
			[ "$c" = ":" ] && json_parse_value "$current_path" "$current_varname" && current_scope="field_separator";
			;;
		"field_separator") 
			[ "$c" = ',' ] && current_scope="root";
			[ "$c" = '}' ] && return;
			;;
		esac
	done
};
json_read() {
	chars_read=0;
	preserve_current_char=0;
	while [ "$chars_read" -lt "$INPUT_LENGTH" ]; do
		json_readc c;
		c=${c:-' '};
		chars_read=$((chars_read + 1));
		[ "$c" = "{" ] && json_parse_object "" "" && return;
		[ "$c" = "[" ] && json_parse_array "" "" && return;
	done
};

json() {
	if [ -z "$@" ]; then
		INPUT=$(cat -);
	else
		INPUT=$(echo "$@");
	fi;
	INPUT_LENGTH="${#INPUT}";
	echo "${INPUT}" | json_read;
};

json "$@"