スプシのデータをJSON化してウェブサイトに取り込む（Sheets API使いません）

=if(and(B4>=date(year(today()),month(today()),1),B4<>""),year($B4)&"-"&text(month($B4),"00")&"-"&text(DAY($B4),"00")&" "&text(C4,"00")&":"&text(D4,"00")&":00","")

=and($B4<today(), $B4<>"")

=TEXTJOIN(",",true,INDIRECT(B3&"!$A$4:A"))

https://docs.google.com/spreadsheets/d/{スプシのid}/edit#gid={なんかのID}

https://spreadsheets.google.com/feeds/list/{$sheet_id}/{$sheet_order}/public/values?alt=json

function get_event_deta() {
	$sheet_id    = '{スプシのID}';
	$sheet_order = '1';
	$data        = "https://spreadsheets.google.com/feeds/list/{$sheet_id}/{$sheet_order}/public/values?alt=json";
	$curl        = curl_init();
	curl_setopt( $curl, CURLOPT_URL, $data );
	curl_setopt( $curl, CURLOPT_CUSTOMREQUEST, 'GET' );
	curl_setopt( $curl, CURLOPT_RETURNTRANSFER, true );
	$response = curl_exec($curl);
	curl_close( $curl );

	if ( ! $json->errors ) {

		$json_decode = json_decode( $response );
		$events      = array();
		foreach ( $json_decode->feed->entry as $value ) {
			$branch         = $value->{'gsx$branch'}->{'$t'};
			$schedule        = explode( ',', $value->{'gsx$detail'}->{'$t'} );
			$events[ $branch ] = $schedule;
		}
	} else {
		$events = 'error';
	}
	return $events;
}

$events  = get_event_deta();
$lastday = gmdate( 'd', strtotime( 'last day of this month' ) );
$c_year  = gmdate( 'Y' );
$c_month = gmdate( 'm' );
$d       = array( '日', '月', '火', '水', '木', '金', '土' );

if ( 'error' === $events ) {
	echo '<p class="text-center mt-5">カレンダーの読み込みに失敗しました。<p>';
} else {
	echo '<table>';
	echo '<caption>' . $c_year . '年' . $month .'月</caption>';
	for ( $i = 1; $i <= $lastday; $i++ ) {
		$c_date   = $c_year . '-' . $c_month . '-' . str_pad( $i, 2, 0, STR_PAD_LEFT );
		$week     = date( 'w', strtotime( $c_date ) );
		$bg_color = '';

		if ( 0 === (int) $week ) {
			$bg_color = ' class="bg_sun"';
		}
		if ( 6 === (int) $week ) {
			$bg_color = ' class="bg_sat"';
		}

		echo '<tr' . $bg_color . '>';
		echo '<td>' . $i . '(' . $d[ (int) $week ].' ) '. '</td>';

		$branch = '';
		foreach ( $events as $name => $items ) {
			foreach ( $items as $date ) {
				$event_date = strtotime( $date );
				if ( $c_date === gmdate( 'Y-m-d', $event_date ) ) {
					$branch .= '<span>' . gmdate( 'H:i', $event_date ) . $name . '</span>';
				}
			}
		}
		echo '<td>' . $branch . '</td>';
		echo '</tr>';
	}
	echo '</table>';
}

/**
 * Get event data.
 *
 * @return $events
 */
function get_event_data() {
	$sheet_id    = '{スプシのID}';
	$sheet_order = '1';
	$data        = "https://spreadsheets.google.com/feeds/list/{$sheet_id}/{$sheet_order}/public/values?alt=json";
	$json        = wp_remote_get( $data );
	if ( ! $json->errors ) {

		$json_decode = json_decode( $json['body'] );
		 $events      = array();
		foreach ( $json_decode->feed->entry as $value ) {
			$school            = $value->{'gsx$branch'}->{'$t'};
			$schedule          = explode( ',', $value->{'gsx$detail'}->{'$t'} );
			 $events[ $branch ] = $schedule;
		}
	} else {
		 $events = 'error';
	}
	return  $events;
}

/**
 * Show event schedule
 *
 * @return $table
 */
function show_event_schedule() {
	$events  = get_event_deta();

	if ( 'error' === $events ) {
		return '<p class="text-center mt-5">カレンダーの読み込みに失敗しました。<p>';
	}

	$lastday = gmdate( 'd', strtotime( 'last day of this month' ) );
	$c_year  = gmdate( 'Y' );
	$c_month = gmdate( 'm' );
	$d       = array( '日', '月', '火', '水', '木', '金', '土' );

	$table  = '<table>';
	$table .= '<caption>' . $c_year . '年' . $c_month . '月</caption>';
	for ( $i = 1; $i <= $lastday; $i++ ) {
		$c_date   = $c_year . '-' . $c_month . '-' . str_pad( $i, 2, 0, STR_PAD_LEFT );
		$week     = gmdate( 'w', strtotime( $c_date ) );
		$bg_color = '';

		if ( 0 === (int) $week ) {
			$bg_color = ' class="bg_sun"';
		}
		if ( 6 === (int) $week ) {
			$bg_color = ' class="bg_sat"';
		}

		$table .= '<tr' . $bg_color . '>';
		$table .= '<td>' . $i . '(' . $d[ (int) $week ] . ')</td>';
		$branch = '';

		foreach ( $events as $name => $items ) {
			foreach ( $items as $date ) {
				$event_date = strtotime( $date );
				if ( gmdate( 'Y-m-d', $event_date ) === $c_date ) {
					$branch .= '<span>' . gmdate( 'H:i', $event_date ) . $name . '</span>';
				}
			}
		}
		$table .= '<td>' . $branch . '</td>';
		$table .= '</tr>';
	}
	$table .= '</table>';

	return $table;
}
add_shortcode( 'show_event_schedule', 'show_event_schedule' );

[show_event_schedule]