<?php

namespace SmallProgramApi\Helper;

/**
 * 电子围栏辅助类
 * 用于判断坐标点是否在电子围栏内
 */
class FenceHelper
{
    /**
     * 判断点是否在多边形内（射线法）
     * @param float $lng 经度
     * @param float $lat 纬度
     * @param array $polygon 多边形坐标数组 [['lng' => x, 'lat' => y], ...]
     * @return bool
     */
    public static function isPointInPolygon($lng, $lat, $polygon)
    {
        if (empty($polygon) || count($polygon) < 3) {
            return false;
        }
        
        $count = count($polygon);
        $inside = false;
        
        for ($i = 0, $j = $count - 1; $i < $count; $j = $i++) {
            $xi = $polygon[$i]['lng'];
            $yi = $polygon[$i]['lat'];
            $xj = $polygon[$j]['lng'];
            $yj = $polygon[$j]['lat'];
            
            if ((($yi > $lat) != ($yj > $lat)) && 
                ($lng < ($xj - $xi) * ($lat - $yi) / ($yj - $yi) + $xi)) {
                $inside = !$inside;
            }
        }
        
        return $inside;
    }
    
    /**
     * 判断点是否在任意一个围栏内
     * @param float $lng 经度
     * @param float $lat 纬度
     * @param array $fences 围栏数据数组
     * @return array 返回结果 ['in_fence' => bool, 'fence_name' => string]
     */
    public static function checkPointInFences($lng, $lat, $fences)
    {
        if (empty($fences)) {
            return ['in_fence' => false, 'fence_name' => ''];
        }
        
        foreach ($fences as $fence) {
            // 只检查启用的围栏
            if (isset($fence['is_active']) && $fence['is_active'] != 1) {
                continue;
            }
            
            // 只处理多边形围栏
            if (isset($fence['fence_type']) && $fence['fence_type'] != 1) {
                continue;
            }
            
            $fenceData = $fence['fence_data'];
            
            // 如果fence_data是字符串，尝试解析
            if (is_string($fenceData)) {
                $fenceData = json_decode($fenceData, true);
                if (json_last_error() !== JSON_ERROR_NONE) {
                    continue;
                }
            }
            
            // 如果fence_data是数组格式（新格式）
            if (is_array($fenceData)) {
                // 检查是否是多个多边形的数组格式
                if (isset($fenceData[0]) && is_array($fenceData[0])) {
                    // 新格式：[{id: '', paths: [{lat: x, lng: y}]}, ...]
                    if (isset($fenceData[0]['paths'])) {
                        foreach ($fenceData as $polygon) {
                            if (isset($polygon['paths']) && is_array($polygon['paths'])) {
                                $points = [];
                                foreach ($polygon['paths'] as $point) {
                                    if (isset($point['lat']) && isset($point['lng'])) {
                                        $points[] = ['lng' => $point['lng'], 'lat' => $point['lat']];
                                    }
                                }
                                
                                if (count($points) >= 3 && self::isPointInPolygon($lng, $lat, $points)) {
                                    return [
                                        'in_fence' => true, 
                                        'fence_name' => $fence['fence_name'] ? $fence['fence_name'] : '配送区域'
                                    ];
                                }
                            }
                        }
                    }
                    // 旧格式：直接是坐标点数组 [{lng: x, lat: y}, ...]
                    else {
                        $points = [];
                        foreach ($fenceData as $point) {
                            if (isset($point['lng']) && isset($point['lat'])) {
                                $points[] = ['lng' => $point['lng'], 'lat' => $point['lat']];
                            }
                        }
                        
                        if (count($points) >= 3 && self::isPointInPolygon($lng, $lat, $points)) {
                            return [
                                'in_fence' => true, 
                                'fence_name' => $fence['fence_name'] ? $fence['fence_name'] : '配送区域'
                            ];
                        }
                    }
                }
            }
        }
        
        return ['in_fence' => false, 'fence_name' => ''];
    }
    
    /**
     * 获取门店的电子围栏数据
     * @param int $storeId 门店ID
     * @return array
     */
    public static function getStoreFences($storeId)
    {
        $FenceModel = new \Common\Model\StoreDeliveryFenceModel();
        return $FenceModel->where(['store_id' => $storeId, 'is_active' => 1])->select();
    }
}