Cacher is the code snippet organizer for pro developers

<?php
/*
Plugin Name: Geotag my posts
Description: Allows you to add location context to your posts, pages or custom post types.<br />Activate the Add-on and then select which post-types you want to geotag. After this you will find a new metabox in the post editor where you can enter an address. <br>To display a map with all geo-tagged posts use the shortcode <code>[agm_gwp_geocoded_posts]</code>
Example:     [agm_gwp_geocoded_posts]
Plugin URI:  http://premium.wpmudev.org/project/wordpress-google-maps-plugin
Version:     1.0
Author:      Ve Bailovity (Incsub)
*/

class Agm_GwpAdminPages {

	private $_data;

	private function __construct() {
		$this->_data = new Agm_GwpModel();
		$this->_add_hooks();
	}

	public static function serve() {
		static $Instance = null;
		if ( null === $Instance ) {
			$me = new Agm_GwpAdminPages();
		}
	}

	private function _add_hooks() {
		add_action(
			'agm_google_maps-options-plugins_options',
			array( $this, 'register_settings' )
		);

		add_action(
			'add_meta_boxes',
			array( $this, 'register_metabox' )
		);
		add_action(
			'save_post',
			array( $this, 'save_metabox_values' )
		);
	}

	public function register_settings() {
		add_settings_section(
			'agm_google_maps_gwp',
			__( 'Geotag my posts', AGM_LANG ),
			'__return_false',
			'agm_google_maps_options_page'
		);

		add_settings_field(
			'agm_google_maps_fbnf_fb',
			__( 'Geotagging metabox', AGM_LANG ),
			array( $this, 'create_post_types_box' ),
			'agm_google_maps_options_page',
			'agm_google_maps_gwp'
		);
	}

	public function create_post_types_box() {
		$selected_types = $this->_data->get_option( 'post_types' );
		$selected_types = $selected_types ? $selected_types : array();
		$post_types = get_post_types( array( 'public' => true ), 'objects' );
		echo '<label for="agm-gwp-post_types">' . __( 'Show geotagging metabox for', AGM_LANG ) . ':</label><br />';
		foreach ( $post_types as $type => $obj ) : ?>
			<label for="agm-gwp-post_type-<?php echo esc_attr( $type ); ?>">
				<input type="checkbox"
					id="agm-gwp-post_type-<?php echo esc_attr( $type ); ?>"
					name="agm_google_maps[gwp-post_types][]"
					value="<?php echo esc_attr( $type ); ?>"
					<?php checked( in_array( $type, $selected_types ) ); ?> />
				<?php echo esc_html( $obj->label ); ?>
			</label><br />
		<?php endforeach;
	}

	public function register_metabox() {
		$post_types = $this->_data->get_option( 'post_types' );
		$post_types = $post_types ? $post_types : array();

		foreach ( $post_types as $type ) {
			add_meta_box(
				'',
				__( 'Location', AGM_LANG ),
				array( $this, 'render_metabox' ),
				$type,
				'side',
				'default'
			);
		}

		// Enqueue dependencies
		global $post, $pagenow;
		if ( ! in_array( $pagenow, array( 'post.php', 'post-new.php' ) ) ) {
			return false; // Editor pages, double-check
		}
		if ( ! is_object( $post ) || ! isset( $post->post_type ) || ! in_array( $post->post_type, $post_types ) ) {
			return false; // Invalid post type
		}

		lib3()->ui->add( AGM_PLUGIN_URL . 'js/admin/geotag-wp.min.js' );
	}

	public function render_metabox() {
		global $post;

		if ( ! $post ) {
			return false;
		}

		$post_id = wp_is_post_revision( $post->ID );
		$post_id = $post_id ? $post_id : $post->ID;

		$lat = get_post_meta( $post_id, '_agm_latitude', true );
		$lng = get_post_meta( $post_id, '_agm_longitude', true );
		?>
		<div id="agm-gwp-location_root">
			<label for="agm-address">
				Address: <input type="text" name="agm-address" id="agm-address" value="" />
			</label>
			<input type="hidden" name="agm-latitude" id="agm-latitude" value="<?php echo esc_attr( $lat ); ?>" />
			<input type="hidden" name="agm-longitude" id="agm-longitude" value="<?php echo esc_attr( $lng ); ?>" />
		</div>
		<?php
	}

	public function save_metabox_values() {
		global $post;

		if ( defined( 'DOING_AJAX' ) && DOING_AUTOSAVE ) {
			return false; // autosave
		}

		if ( ! $post ) {
			return false;
		}

		$post_id = wp_is_post_revision( $post->ID );
		$post_id = $post_id ? $post_id : $post->ID;

		$post_types = $this->_data->get_option( 'post_types' );
		$post_types = $post_types ? $post_types : array();

		if ( ! in_array( $post->post_type, $post_types ) ) {
			return false;
		}

		$address = ! empty( $_POST['agm-address'] ) ? wp_strip_all_tags( $_POST['agm-address'] ) : false;
		$lat = ! empty( $_POST['agm-latitude'] ) ? (float) $_POST['agm-latitude'] : false;
		$lng = ! empty( $_POST['agm-longitude'] ) ? (float) $_POST['agm-longitude'] : false;

		if ( $lat && $lng ) {
			return $this->_update_post_geotag( $post_id, $lat, $lng );
		}

		if ( ! $address ) {
			return false;
		}

		$result = $this->_data->geocode_address( $address );
		return $this->_update_post_geotag(
			$post_id,
			$result->geometry->location->lat,
			$result->geometry->location->lng
		);
	}

	private function _update_post_geotag( $post_id, $lat, $lng ) {
		update_post_meta( $post_id, '_agm_latitude', $lat );
		update_post_meta( $post_id, '_agm_longitude', $lng );
	}

}


class Agm_GwpModel {

	private $_data;
	private $_model;

	public function __construct() {
		$this->_data = apply_filters( 'agm_google_maps-options-gwp', get_option( 'agm_google_maps' ) );
		$this->_model = new AgmMapModel();
	}

	public function geocode_address( $address ) {
		return $this->_model->geocode_address( $address );
	}

	public function get_option( $key, $default = false ) {
		$key = "gwp-{$key}";
		return isset( $this->_data[$key] ) ? $this->_data[$key] : $default;
	}

	public function get_all_geolocated_posts( $limit = false ) {
		global $wpdb;
		$limit = (int) $limit;
		$limit = $limit ? "LIMIT {$limit}" : '';

		$sql = "
			SELECT *
			FROM {$wpdb->posts} AS p,
				{$wpdb->postmeta} AS pm
			WHERE pm.meta_key = '_agm_longitude'
			AND p.ID = pm.post_id
			{$limit}
		";
		return $wpdb->get_results( $sql );
	}

	public function get_all_geolocated_posts_as_markers( $limit = false ) {
		$result = array();
		$posts = $this->get_all_geolocated_posts( $limit );
		foreach ( $posts as $post ) {
			$result[] = $this->post_to_marker( $post );
		}
		return $result;
	}

	public function get_the_excerpt( $post ) {
		if ( $post->post_excerpt ) {
			$str = $post->post_excerpt;
		} else {
			$str = wp_strip_all_tags( $post->post_content );
			$str = strip_shortcodes( $str );
			$str = preg_replace( '/\r|\n/', ' ', $str );

			if ( strlen( $str ) > 247 ) {
				$str = substr( $str, 0, 247 ) . '...';
			}
		}
		return apply_filters( 'get_the_excerpt', $str );
	}

	public function post_to_marker( $post ) {
		$excerpt = $this->get_the_excerpt( $post );
		$body = '<p>' .
				$excerpt .
			'</p>' .
			'<a href="' . get_permalink( $post->ID ) . '">' .
				__( 'Read more', AGM_LANG ) .
			'</a>';

		return array(
			'title' => $post->post_title,
			'body' => $body,
			'icon' => 'marker.png',
			'position' => array(
				get_post_meta( $post->ID, '_agm_latitude', true ),
				get_post_meta( $post->ID, '_agm_longitude', true ),
			),
			'disposition' => 'post_marker',
		);
	}

	public function find_nearby_posts( $lat, $lng, $distance ) {
		global $wpdb;
		$data = $this->_model->find_bounding_coordinates( $lat, $lng, $distance );
		list( $min_lat, $max_lat, $min_lng, $max_lng ) = $data;

		$sql = "
		SELECT posts.*
		FROM {$wpdb->posts} posts
		WHERE EXISTS(
			SELECT DISTINCT post_id
			FROM (
				SELECT
					latitude,
					longitude,
					t1.post_id
				FROM
					(
						SELECT post_id, meta_value as longitude
						FROM {$wpdb->postmeta}
						WHERE meta_key='_agm_longitude'
					) as t1
				LEFT JOIN
					(
						SELECT post_id, meta_value as latitude
						FROM {$wpdb->postmeta}
						WHERE meta_key='_agm_latitude'
					) as t2
				ON t1.post_id = t2.post_id
			) as meta
			WHERE
				CAST( longitude AS DECIMAL(10,5) ) > %d
				AND CAST( longitude AS DECIMAL(10,5) ) < %d
				AND CAST( latitude AS DECIMAL(10,5) ) > %d
				AND CAST( latitude AS DECIMAL(10,5) ) < %d
				AND meta.post_id=posts.ID
		)
		";
		$sql = $wpdb->prepare( $sql, $min_lng, $max_lng, $min_lat, $max_lat );
		return $wpdb->get_results( $sql );
	}
}


class Agm_GwpUserPages {

	private $_data;

	private $_model;

	private function __construct() {
		$this->_data = new Agm_GwpModel();
		$this->_model = new AgmMapModel();
		$this->_add_hooks();
	}

	public static function serve() {
		static $Instance = null;
		if ( null === $Instance ) {
			$Instance = new Agm_GwpUserPages();
		}
	}

	private function _add_hooks() {
		add_action(
			'agm-user-scripts',
			array( $this, 'load_scripts' )
		);

		add_shortcode(
			'agm_gwp_geocoded_posts',
			array( $this, 'all_geocoded_posts_map' )
		);

		// Nearby posts argument
		add_filter(
			'agm-shortcode-defaults',
			array( $this, 'set_attribute_defaults' )
		);
		add_filter(
			'agm-shortcode-overrides',
			array( $this, 'process_overrides' ),
			10, 2
		);
		add_filter(
			'agm-create-tag',
			array( $this, 'process_tag' ),
			10, 2
		);
	}

	public function set_attribute_defaults( $args ) {
		$args['nearby_posts'] = false;
		$args['nearby_boundaries'] = false;
		$args['nearby_posts_in_list'] = false;
		$args['nearby_within'] = 1000;
		return $args;
	}

	public function process_overrides( $overrides, $args ) {
		$_yes = array( 'yes', 'true', 'on' );
		if ( isset( $args['nearby_posts'] ) ) {
			$overrides['nearby_posts'] = in_array( $args['nearby_posts'], $_yes );
		}

		if ( isset( $args['nearby_boundaries'] ) ) {
			$overrides['nearby_boundaries'] = in_array( $args['nearby_boundaries'], $_yes );
		}
		if ( isset( $args['nearby_posts_in_list'] ) ) {
			$overrides['nearby_posts_in_list'] = in_array( $args['nearby_posts_in_list'], $_yes );
		}
		if ( isset( $args['nearby_within'] ) ) {
			$overrides['nearby_within'] = (int) $args['nearby_within'];
		}
		return $overrides;
	}

	public function process_tag( $map, $overrides ) {
		if ( empty( $overrides['nearby_posts'] ) ) {
			return $map;
		}
		$within = (int) $overrides['nearby_within'] ? (int) $overrides['nearby_within'] : 1000;
		$seen = $to_add = array();

		foreach ( $map['markers'] as $marker ) {
			$posts = $this->_data->find_nearby_posts( $marker['position'][0], $marker['position'][1], $within );
			foreach ( $posts as $post ) {
				if ( in_array( $post->ID, $seen ) ) {
					continue; // Only add once
				}
				$to_add[] = $this->_data->post_to_marker( $post );
				$seen[] = $post->ID;
			}
		}
		// Reverse the order, so not to skew map default centering
		$map['markers'] = array_merge( $to_add, $map['markers'] );
		return $map;
	}

	public function all_geocoded_posts_map( $args = array(), $content = '' ) {
		$_yes = array( 'yes', 'true', 'on' );
		$args = is_array( $args ) ? $args : array();

		$map = $this->_model->get_map_defaults();
		$map['defaults'] = $this->_model->get_map_defaults();
		$map['id'] = 'geocoded_posts-' . md5( microtime() );
		$map['show_map'] = 1;
		// [BUG] Hard sets the markers at 6
		// $map['markers'] = $this->_data->get_all_geolocated_posts_as_markers( 6 );
    
		// [FIX] Allow all markers to be displayed - James Morris [@jrmorris77] (Incsub)
		$map['markers'] = $this->_data->get_all_geolocated_posts_as_markers();

		foreach ( $args as $key => $arg ) {
			if ( in_array( $arg, $_yes ) ) {
				$args[$key] = 1;
			}
		}
		$args['nearby_posts'] = false; // ... or the world explodes
		if ( ! empty( $args['show_markers'] ) && empty( $args['nearby_posts_in_list'] ) ) {
			$args['nearby_posts_in_list'] = true; // Auto-set if not explicitly requested otherwise
		}

		$codec = new AgmMarkerReplacer();
		return $codec->create_tag( $map, $args );
	}

	public function load_scripts() {
		lib3()->ui->add( AGM_PLUGIN_URL . 'js/user/geotag-wp.min.js', 'front' );
	}
}

if ( is_admin() ) {
	Agm_GwpAdminPages::serve();
} else {
	Agm_GwpUserPages::serve();
}