<?php
namespace Common\Model;

use Common\Model\BaseModel;

/**
 * 骑手位置模型
 * Class RiderLocationModel
 * @package Common\Model
 */
class RiderLocationModel extends BaseModel
{
    /**
     * 表名
     * @var string
     */
    protected $tableName = 'rider_location';

    /**
     * 添加位置记录
     * @param array $data
     * @return int|false
     */
    public function addLocation($data)
    {
        return $this->add($data);
    }

    /**
     * 批量添加位置记录
     * @param array $dataList
     * @return int|false
     */
    public function addLocationBatch($dataList)
    {
        return $this->addAll($dataList);
    }

    /**
     * 获取骑手最新位置
     * @param int $riderId 骑手ID
     * @return array
     */
    public function getLatestLocation($riderId)
    {
        return $this->where(['rider_id' => $riderId])
            ->order('add_time DESC')
            ->find();
    }

    /**
     * 获取骑手位置轨迹
     * @param int $riderId 骑手ID
     * @param string $startTime 开始时间
     * @param string $endTime 结束时间
     * @param int $limit 限制数量
     * @return array
     */
    public function getLocationTrack($riderId, $startTime = '', $endTime = '', $limit = 100)
    {
        $where = ['rider_id' => $riderId];
        
        if (!empty($startTime)) {
            $where['add_time'][] = ['egt', $startTime];
        }
        
        if (!empty($endTime)) {
            $where['add_time'][] = ['elt', $endTime];
        }
        
        return $this->where($where)
            ->order('add_time ASC')
            ->limit($limit)
            ->select();
    }

    /**
     * 获取指定范围内的骑手
     * @param float $centerLat 中心纬度
     * @param float $centerLng 中心经度
     * @param float $radius 半径(公里)
     * @param array $riderIds 指定骑手ID列表(可选)
     * @return array
     */
    public function getRidersInRange($centerLat, $centerLng, $radius, $riderIds = [])
    {
        // 计算经纬度范围
        $latRange = $radius / 111; // 1度纬度约等于111公里
        $lngRange = $radius / (111 * cos(deg2rad($centerLat))); // 经度范围需要考虑纬度
        
        $minLat = $centerLat - $latRange;
        $maxLat = $centerLat + $latRange;
        $minLng = $centerLng - $lngRange;
        $maxLng = $centerLng + $lngRange;
        
        $where = [
            'lat' => ['between', [$minLat, $maxLat]],
            'lng' => ['between', [$minLng, $maxLng]]
        ];
        
        if (!empty($riderIds)) {
            $where['rider_id'] = ['in', $riderIds];
        }
        
        // 获取每个骑手的最新位置
        $subQuery = $this->field('rider_id, MAX(add_time) as max_time')
            ->where($where)
            ->group('rider_id')
            ->buildSql();
        
        $locations = $this->alias('rl1')
            ->join("({$subQuery}) rl2 ON rl1.rider_id = rl2.rider_id AND rl1.add_time = rl2.max_time")
            ->field('rl1.*')
            ->select();
        
        // 精确计算距离并过滤
        $result = [];
        foreach ($locations as $location) {
            $distance = $this->calculateDistance($centerLat, $centerLng, $location['lat'], $location['lng']);
            if ($distance <= $radius) {
                $location['distance'] = $distance;
                $result[] = $location;
            }
        }
        
        // 按距离排序
        usort($result, function($a, $b) {
            return $a['distance'] <=> $b['distance'];
        });
        
        return $result;
    }

    /**
     * 计算两点间距离
     * @param float $lat1 纬度1
     * @param float $lng1 经度1
     * @param float $lat2 纬度2
     * @param float $lng2 经度2
     * @return float 距离(公里)
     */
    public function calculateDistance($lat1, $lng1, $lat2, $lng2)
    {
        if (empty($lat1) || empty($lng1) || empty($lat2) || empty($lng2)) {
            return 999;
        }

        $earthRadius = 6371; // 地球半径，单位：公里

        $lat1Rad = deg2rad($lat1);
        $lng1Rad = deg2rad($lng1);
        $lat2Rad = deg2rad($lat2);
        $lng2Rad = deg2rad($lng2);

        $deltaLat = $lat2Rad - $lat1Rad;
        $deltaLng = $lng2Rad - $lng1Rad;

        $a = sin($deltaLat / 2) * sin($deltaLat / 2) +
             cos($lat1Rad) * cos($lat2Rad) *
             sin($deltaLng / 2) * sin($deltaLng / 2);
        $c = 2 * atan2(sqrt($a), sqrt(1 - $a));

        return $earthRadius * $c;
    }

    /**
     * 清理过期位置记录
     * @param int $days 保留天数
     * @return int
     */
    public function cleanExpiredLocations($days = 7)
    {
        $expireDate = date('Y-m-d H:i:s', strtotime("-{$days} days"));
       // 删除过期的位置记录
        return $this->where(['add_time' => ['lt', $expireDate]])->delete();
    }

    /**
     * 获取骑手活动统计
     * @param int $riderId 骑手ID
     * @param string $date 日期
     * @return array
     */
    public function getRiderActivityStats($riderId, $date = '')
    {
        if (empty($date)) {
            $date = date('Y-m-d');
        }
        
        $startTime = $date . ' 00:00:00';
        $endTime = $date . ' 23:59:59';
        
        $where = [
            'rider_id' => $riderId,
            'add_time' => ['between', [$startTime, $endTime]]
        ];
        
        $locations = $this->where($where)
            ->order('add_time ASC')
            ->select();
        
        if (empty($locations)) {
            return [
                'total_distance' => 0,
                'active_time' => 0,
                'location_count' => 0,
                'first_location_time' => '',
                'last_location_time' => ''
            ];
        }
        
        // 计算总距离
        $totalDistance = 0;
        for ($i = 1; $i < count($locations); $i++) {
            $distance = $this->calculateDistance(
                $locations[$i-1]['lat'], 
                $locations[$i-1]['lng'],
                $locations[$i]['lat'], 
                $locations[$i]['lng']
            );
            $totalDistance += $distance;
        }
        
        // 计算活动时间
        $firstTime = strtotime($locations[0]['add_time']);
        $lastTime = strtotime($locations[count($locations)-1]['add_time']);
        $activeTime = $lastTime - $firstTime;
        
        return [
            'total_distance' => round($totalDistance, 2),
            'active_time' => $activeTime,
            'location_count' => count($locations),
            'first_location_time' => $locations[0]['add_time'],
            'last_location_time' => $locations[count($locations)-1]['add_time']
        ];
    }

    /**
     * 获取区域内骑手密度
     * @param float $centerLat 中心纬度
     * @param float $centerLng 中心经度
     * @param float $radius 半径(公里)
     * @param int $timeRange 时间范围(分钟)
     * @return array
     */
    public function getRiderDensity($centerLat, $centerLng, $radius, $timeRange = 30)
    {
        $startTime = date('Y-m-d H:i:s', strtotime("-{$timeRange} minutes"));
        
        // 计算经纬度范围
        $latRange = $radius / 111;
        $lngRange = $radius / (111 * cos(deg2rad($centerLat)));
        
        $minLat = $centerLat - $latRange;
        $maxLat = $centerLat + $latRange;
        $minLng = $centerLng - $lngRange;
        $maxLng = $centerLng + $lngRange;
        
        $where = [
            'lat' => ['between', [$minLat, $maxLat]],
            'lng' => ['between', [$minLng, $maxLng]],
            'add_time' => ['egt', $startTime]
        ];
        
        // 获取活跃骑手数量
        $activeRiders = $this->where($where)
            ->field('rider_id')
            ->group('rider_id')
            ->select();
        
        $riderCount = count($activeRiders);
        $area = pi() * $radius * $radius; // 圆形区域面积
        $density = $area > 0 ? $riderCount / $area : 0;
        
        return [
            'rider_count' => $riderCount,
            'area' => round($area, 2),
            'density' => round($density, 4),
            'radius' => $radius,
            'time_range' => $timeRange
        ];
    }

    /**
     * 预测骑手到达时间
     * @param int $riderId 骑手ID
     * @param float $destLat 目标纬度
     * @param float $destLng 目标经度
     * @param float $avgSpeed 平均速度(公里/小时)
     * @return array
     */
    public function predictArrivalTime($riderId, $destLat, $destLng, $avgSpeed = 20)
    {
        // 获取骑手最新位置
        $latestLocation = $this->getLatestLocation($riderId);
        
        if (empty($latestLocation)) {
            return [
                'estimated_time' => 0,
                'distance' => 0,
                'error' => '无法获取骑手位置'
            ];
        }
        
        // 计算距离
        $distance = $this->calculateDistance(
            $latestLocation['lat'], 
            $latestLocation['lng'],
            $destLat, 
            $destLng
        );
        
        // 计算预计时间(分钟)
        $estimatedTime = ($distance / $avgSpeed) * 60;
        
        // 考虑交通因素，增加20%的时间
        $estimatedTime *= 1.2;
        
        return [
            'estimated_time' => round($estimatedTime, 0),
            'distance' => round($distance, 2),
            'avg_speed' => $avgSpeed,
            'current_location' => [
                'lat' => $latestLocation['lat'],
                'lng' => $latestLocation['lng'],
                'record_time' => $latestLocation['add_time']
            ]
        ];
    }

    /**
     * 删除位置记录
     * @param array $where 删除条件
     * @return int
     */
    public function deleteLocation($where)
    {
        return $this->where($where)->delete();
    }
}