#!/usr/bin/php

<?php

	require_once __DIR__.'/../../include/php/const';


	function chip_state($p_id_chip, $p_state){

		$g_pins  = null;
		$g_state = null;



		/* [1] Cache chips
		=========================================================*/
		/* (1) Get file handler */
		$f_chips = new SplFileObject(CHIPS_CONF, 'r');

		/* (2) Parse line by line */
		while( !$f_chips->eof() ){

			// {1} Try to parse current line //
			$parsed = json_decode($f_chips->fgets(), true);

			// {2} If cannot parse, go to next //
			if( is_null($parsed) )
				continue;

			// {3} Check if choosen pin //
			if( $parsed[0] == $p_id_chip ){

				// store pin list
				$g_pins = $parsed[1];

				/* (3) Check if choosen state */
				foreach($parsed[2] as $state=>$pinValues){

					if( "$state" === "$p_state" ){
						
						// store state values
						$g_state = $pinValues;
						break;
					}

				}

				break;
			}
		}

		/* (3) If chip not found -> abort */
		if( is_null($g_pins) || is_null($g_state) )
			return 127;
			


		/* [2] Set chip to choosen state
		=========================================================*/
		/* (1) Activate pin + set OUT mode */
		foreach($g_pins as $pinNumber)

			// if failed -> propagate error
			if( syscall(SOURCE_DIR."/lib/gpio/out {$pinNumber}") == false )
				return 127;

		/* (2) For each pin, set the associated value */
		foreach($g_state as $pinIndex=>$pinValue){

			// {1} set value to LOW if 0 //
			if( $pinValue == 0 ){

				if( syscall(SOURCE_DIR."/lib/gpio/low ".$g_pins[$pinIndex]) == false )
					return 127;

			// {2} set value to HIGH if not 0 //
			}else{

				if( syscall(SOURCE_DIR."/lib/gpio/high ".$g_pins[$pinIndex]) == false )
					return 127;
			}

		}


		return 0;

	}


	/* [1] Check argument (chip position, chip state)
	=========================================================*/
	if( $argc < 3 || !preg_match('@^\d+$@', $argv[1]) || !preg_match('@^[A-Za-z0-9]{1}$@', $argv[2]) ){
		echo 127;
		die(127);
	}

	/* [2] Launch main script
	=========================================================*/
	$exec = chip_state($argv[1], $argv[2]);

	echo $exec;
	die($exec);
?>