#!/usr/bin/php

<?php

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


	function globalstate_update(){


		/* [1] Fetch global state
		=========================================================*/
		$GLOBAL_STATE = [];

		/* (1) Fetch from file */
		$f_gstate = @file_get_contents(STATE_CONF);

		/* (2) Manage errors */
		if( $f_gstate === false ){
			slog('Cannot access GLOBAL STATE file', 'global-state:update');
			return 127;
		}

		/* (3) Remove surrounding spaces */
		$f_gstate = preg_replace('@^\s+@', '', $f_gstate);
		$f_gstate = preg_replace('@\s+$@', '', $f_gstate);

		/* (4) Extract */
		$GLOBAL_STATE = $f_gstate;


		/* [2] Cache global state to chip states
		=========================================================*/
		$CHIP_STATE = null;

		/* (1) Fetch from file */
		$f_cstates = new SplFileObject(STATES_CONF, 'r');

		/* (2) Section Title */
		if( $f_cstates === false ){
			slog('Cannot access GLOBAL/CHIP STATES file', 'global-state:update');
			return 127;
		}

		/* (3) Parse line by line */
		while( !$f_cstates->eof() ){

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

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

			// {3} Check if GLOBAL STATE matches CURRENT state //
			$failed = false;

			for( $c = 0 ; $c < strlen($GLOBAL_STATE) || $c < strlen($parsed[0]) ; $c++ ){
				// {3.1} If 'X' -> whatever state //
				if( $parsed[0][$c] == 'X' )
					continue;

				// {3.2} Else, if different -> fail //
				else if( $parsed[0][$c] != $GLOBAL_STATE[$c] ){
					$failed = true;
					break;
				}
					
			}

			// {4} If not failed -> state to keep //
			if( !$failed ){
				slog("Current state '$GLOBAL_STATE' matches '{$parsed[0]}'", 'global-state:update');
				$CHIP_STATE = $parsed[1];
				break;
			}

		}

		/* (4) If no CHIP_STATE set -> abort */
		if( is_null($CHIP_STATE) ){
			slog("Cannot find a chip_state for the current global state '{$GLOBAL_STATE}'", 'global-state');
			return 127;
		}




		/* [2] Update 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 position available in GLOBAL_STATE //
			if( isset($CHIP_STATE[$parsed[0]]) ){

				/* (1) If CHIP STATE value is 'x' -> do nothing */
				if( $CHIP_STATE[$parsed[0]] == 'x' )
					continue;

				/* (2) If state does not exist -> go to next chip */
				if( !isset($parsed[2][$CHIP_STATE[$parsed[0]]]) )
					continue;

				/* (3) Use variables to be more human-readable */
				$position = $parsed[0];
				$state    = $CHIP_STATE[$parsed[0]];

				/* (3) Set state */
				$updated = syscall(SOURCE_DIR."/lib/global-state/set {$position} {$state}");

				/* (4) If error */
				if( $updated === false )
					slog("Cannot set ${position} chip to state {$state}", 'global-state:update');

			}
		}
		return 0;

	}


	/* [3] Launch main script
	=========================================================*/
	$exec = globalstate_update();

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