<?php

/**
 * [WeEngine System] Copyright (c) 2013 WE7.CC
 */
defined('IN_IA') or exit('Access Denied');
define(EARTH_RADIUS, 6371); //地球半径，平均半径为6371km

class We7_businessModuleProcessor extends WeModuleProcessor {

    public function respond() {
        global $_W;
        $lat = $this->message['location_x'];
        $lng = $this->message['location_y'];

        $range = isset($this->module['config']['range']) ? $this->module['config']['range'] : 5;

        $point = $this->squarePoint($lng, $lat, $range);

        $sql = "SELECT id, title, thumb, content, lat, lng FROM " . tablename('business') . " WHERE weid = '{$_W['weid']}' AND lat<>0 AND lat >= '{$point['right-bottom']['lat']}' AND
					 lat <= '{$point['left-top']['lat']}' AND lng >= '{$point['left-top']['lng']}' AND lng <= '{$point['right-bottom']['lng']}'";
        $result = pdo_fetchall($sql);

        if (empty($result)) {
            $hintInfo = $this->module['config']['info'] ? $this->module['config']['info'] : '抱歉，系统中的商户不在您附近！';
            return $this->respText($hintInfo);
        }

        $news = array();
        $min = -1;
        foreach ($result as &$row) {
            $row['distance'] = $this->getDistance($lat, $lng, $row['lat'], $row['lng']);
            if ($min < 0 || $row['distance'] < $min) {
                $min = $row['distance'];
            }
        }
        unset($row);

        $temp = array();
        for ($i = 0; $i < 8; $i++) {
            foreach ($result as $j => $row) {
                if (empty($temp['distance']) || $row['distance'] < $temp['distance']) {
                    $temp = $row;
                    $h = $j;
                }
            }
            if (!empty($temp)) {
                $news[] = array(
                    'title' => $temp['title'] . '(距' . $temp['distance'] . '米)',
                    'description' => cutstr(strip_tags($temp['content']), 300),
                    'picurl' => $_W['attachurl'] . $temp['thumb'],
                    'url' => $this->createMobileUrl('detail', array('id' => $temp['id'])),
                );
                unset($result[$h]);
                $temp = array();
            }
        }
        return $this->respNews($news);
    }

    /**
     * 计算某个经纬度的周围某段距离的正方形的四个点
     *
     * @param lng float 经度
     * @param lat float 纬度
     * @param distance float 该点所在圆的半径，该圆与此正方形内切，默认值为0.5千米
     * @return array 正方形的四个点的经纬度坐标
     */
    public function squarePoint($lng, $lat, $distance = 0.5) {

        $dlng = 2 * asin(sin($distance / (2 * EARTH_RADIUS)) / cos(deg2rad($lat)));
        $dlng = rad2deg($dlng);

        $dlat = $distance / EARTH_RADIUS;
        $dlat = rad2deg($dlat);

        return array(
            'left-top' => array('lat' => $lat + $dlat, 'lng' => $lng - $dlng),
            'right-top' => array('lat' => $lat + $dlat, 'lng' => $lng + $dlng),
            'left-bottom' => array('lat' => $lat - $dlat, 'lng' => $lng - $dlng),
            'right-bottom' => array('lat' => $lat - $dlat, 'lng' => $lng + $dlng)
        );
    }

    function getDistance($lat1, $lng1, $lat2, $lng2, $len_type = 1, $decimal = 2) {
        $radLat1 = $lat1 * M_PI / 180;
        $radLat2 = $lat2 * M_PI / 180;
        $a = $lat1 * M_PI / 180 - $lat2 * M_PI / 180;
        $b = $lng1 * M_PI / 180 - $lng2 * M_PI / 180;

        $s = 2 * asin(sqrt(pow(sin($a / 2), 2) + cos($radLat1) * cos($radLat2) * pow(sin($b / 2), 2)));
        $s = $s * EARTH_RADIUS;
        $s = round($s * 1000);
        if ($len_type > 1) {
            $s /= 1000;
        }
        return round($s, $decimal);
    }

}