<?php

namespace app\api\controller;

use think\Db;
use app\common\library\NationalArea;

/**
 * 用户端 · 首页与展示（Module-HOME）
 * 路由：
 *   GET /api/v1/home/banners        H1 轮播广告位
 *   GET /api/v1/home/categories     H2 分类导航（含二级分类树与实拍图）
 *   GET /api/v1/home/search/hot     H3 热门搜索
 *   GET /api/v1/home/feed           H4 信息流（支持全国省/市/区县筛选 + 一二级分类筛选 + 距离排序）
 *   GET /api/v1/home/areas          H5 全国服务区域列表（平铺省/市/区县）
 *   GET /api/v1/home/locate         H6 按定位坐标匹配全国当前区县
 */
class Home extends V1
{
    /**
     * H1 首页轮播广告位接口
     * GET /api/v1/home/banners  →  [{id,title,image,link,color}]
     * 规则：仅返回 enabled=1，按 sort asc, id desc 排序；若配置了相对路径图片，则自动使用 cdnurl 拼接完整域名地址
     *
     * @return void
     */
    public function banners()
    {
        $rows = Db::name('fc_banner')
            ->where('enabled', 1)
            ->order('sort asc, id desc')
            ->select();

        $list = [];
        foreach ($rows as $row) {
            $image = (string)$row['image'];
            if ($image !== '' && !preg_match('/^https?:\/\//i', $image)) {
                $image = cdnurl($image, true);
            }
            $list[] = [
                'id'    => (int)$row['id'],
                'title' => (string)$row['title'],
                'image' => $image,
                'link'  => (string)$row['link'],
                'color' => (string)$row['color'],
            ];
        }
        $this->ok($list);
    }

    /**
     * H2 分类导航（一级分类 + 二级分类树，附带农产品实拍图）
     * GET /api/v1/home/categories  →  [{id,pid,name,iconKey,icon,image,color,count,children:[...]}]
     * 规则：仅 enabled=1，按 sort asc；一级分类下挂 children 二级分类列表
     *
     * @return void
     */
    public function categories()
    {
        $rows = Db::name('fc_category')
            ->where('enabled', 1)
            ->order('pid asc, sort asc, id asc')
            ->select();

        $parents = [];
        $childrenMap = [];

        foreach ($rows as $row) {
            $id = (int)$row['id'];
            $pid = isset($row['pid']) ? (int)$row['pid'] : 0;
            $iconKey = (string)$row['icon_key'];
            $rawImage = isset($row['image']) ? (string)$row['image'] : '';
            $iconPath = $this->resolveCategoryIconPath($id, $iconKey, $rawImage);
            $imagePath = $rawImage !== '' ? $rawImage : $iconPath;

            $item = [
                'id'      => $id,
                'pid'     => $pid,
                'name'    => (string)$row['name'],
                'iconKey' => $iconKey,
                'icon'    => $iconPath,
                'image'   => $imagePath,
                'color'   => (string)$row['color'],
                'kind'    => isset($row['kind']) && $row['kind'] === 'farm' ? 'farm' : 'general',
                'count'   => (int)$row['post_count'],
            ];

            if ($pid === 0) {
                $item['children'] = [];
                $parents[$id] = $item;
            } else {
                if (!isset($childrenMap[$pid])) {
                    $childrenMap[$pid] = [];
                }
                $childrenMap[$pid][] = $item;
            }
        }

        $list = [];
        foreach ($parents as $pid => $parent) {
            $parent['children'] = isset($childrenMap[$pid]) ? $childrenMap[$pid] : [];
            $list[] = $parent;
        }

        // 兜底：若数据库中仅有未挂载父级的孤立分类，直接返回
        if (empty($list) && !empty($childrenMap)) {
            foreach ($childrenMap as $group) {
                foreach ($group as $c) {
                    $c['children'] = [];
                    $list[] = $c;
                }
            }
        }

        $this->ok($list);
    }

    /**
     * H3 热门搜索
     * GET /api/v1/home/search/hot  →  [string]
     * 规则：读配置 home.hotKeywords，未配置则返回农产品热门搜索词
     *
     * @return void
     */
    public function hotKeywords()
    {
        $default = ['有机花菜', '高山大白菜', '红富士苹果', '大棚草莓', '修文猕猴桃'];
        $keywords = $this->cfg('home.hotKeywords', $default);
        if (!is_array($keywords) || !$keywords) {
            $keywords = $default;
        }
        $this->ok(array_values($keywords));
    }

    /**
     * H5 全国服务区域列表（平铺：每条记录自带省 / 市 / 区县）
     * GET /api/v1/home/areas  →  [{id,province,city,district,lat,lng}]
     * 规则：默认开放全国所有省市区县，供小程序端省/市/区三级联动选择。
     *
     * @return void
     */
    public function areas()
    {
        $list = NationalArea::all();
        $this->ok($list);
    }

    /**
     * H6 按定位坐标匹配全国当前服务区域（省/市/区县）
     * GET /api/v1/home/locate?lat=&lng=  →  {areaId,province,city,district,distance}
     * 规则：在全国区县字典中匹配距离当前坐标最近的区县。
     *
     * @return void
     */
    public function locate()
    {
        $lat = $this->input('lat', null);
        $lng = $this->input('lng', null);
        if (!is_numeric($lat) || !is_numeric($lng)) {
            $this->ok(null);
        }
        $lat = (float)$lat;
        $lng = (float)$lng;
        if ($lat < -90 || $lat > 90 || $lng < -180 || $lng > 180 || ($lat == 0.0 && $lng == 0.0)) {
            $this->ok(null);
        }

        $matched = NationalArea::locate($lat, $lng);
        $this->ok($matched);
    }

    /**
     * H4 信息流
     * GET /api/v1/home/feed  {categoryId?,subCategoryId?,keyword?,province?,city?,areaId?,area?,sort?,lat?,lng?,page,size}
     *   →  {list,page,size,total,hasMore}
     * 规则：仅 audit_status=1 AND status=1 AND deletetime IS NULL
     *
     * @return void
     */
    public function feed()
    {
        list($page, $size) = $this->pager();

        $categoryId = (int)$this->input('categoryId', 0);
        $subCategoryId = (int)$this->input('subCategoryId', 0);
        $keyword = trim((string)$this->input('keyword', ''));
        $province = trim((string)$this->input('province', ''));
        $city = trim((string)$this->input('city', ''));
        $area = trim((string)$this->input('area', ''));
        $areaId = (int)$this->input('areaId', 0);
        if (!$areaId) {
            $areaId = (int)$this->input('districtId', 0);
        }
        $sort = (string)$this->input('sort', '');

        foreach (['province', 'city', 'area', 'keyword', 'sort'] as $strVar) {
            if ($$strVar === 'undefined' || $$strVar === 'null') {
                $$strVar = '';
            }
        }
        if (in_array($province, ['全部', '全国', '不限'], true)) {
            $province = '';
        }
        if (in_array($city, ['全部', '全市', '全州', '不限'], true)) {
            $city = '';
        }
        if (in_array($area, ['全部', '全区', '全城', '全国', '不限'], true)) {
            $area = '';
        }

        // 若传入的 categoryId 本身是二级分类（pid > 0），自动作为二级分类匹配
        $catRow = $categoryId > 0 ? Db::name('fc_category')->where('id', $categoryId)->find() : null;
        $isSubCatId = $catRow && !empty($catRow['pid']) && (int)$catRow['pid'] > 0;

        $applyCategory = function ($q) use ($categoryId, $subCategoryId, $isSubCatId) {
            if ($subCategoryId > 0) {
                $q->where(function ($w) use ($subCategoryId) {
                    $w->where('sub_category_id', $subCategoryId)->whereOr('category_id', $subCategoryId);
                });
                return;
            }
            if ($categoryId > 0) {
                if ($isSubCatId) {
                    $q->where(function ($w) use ($categoryId) {
                        $w->where('sub_category_id', $categoryId)->whereOr('category_id', $categoryId);
                    });
                } else {
                    $q->where('category_id', $categoryId);
                }
            }
        };

        $applyArea = function ($q) use ($province, $city, $area, $areaId) {
            if ($areaId > 0) {
                $natRow = NationalArea::findById($areaId);
                if (!$natRow) {
                    $natRow = Db::name('fc_area')->where('id', $areaId)->find();
                }
                if ($natRow) {
                    $q->where(function ($w) use ($natRow) {
                        $w->where('district_id', (int)$natRow['id'])->whereOr('area', (string)$natRow['district']);
                    });
                } else {
                    $q->where('district_id', $areaId);
                }
                return;
            }
            if ($area !== '') {
                $q->where('area', $area);
                return;
            }
            if ($city !== '') {
                $cityDistricts = [];
                foreach (NationalArea::all() as $item) {
                    if ($item['city'] === $city || rtrim($item['city'], '市') === rtrim($city, '市')) {
                        $cityDistricts[] = $item['district'];
                    }
                }
                $q->where(function ($w) use ($city, $cityDistricts) {
                    $w->where('city', $city);
                    if (!empty($cityDistricts)) {
                        $w->whereOr('area', 'in', array_slice(array_unique($cityDistricts), 0, 100));
                    }
                });
                return;
            }
            if ($province !== '') {
                $q->where('province', $province);
            }
        };

        $applyPaid = function ($q) {
            $q->where(function ($w) {
                $w->where('amount', 'null')->whereOr('amount', '<=', 0)->whereOr('is_paid', 1);
            });
        };

        $query = Db::name('fc_post')
            ->where('audit_status', 1)
            ->where('status', 1)
            ->whereNull('deletetime');
        $applyCategory($query);
        if ($keyword !== '') {
            $query->where('title', 'like', '%' . $keyword . '%');
        }
        $applyArea($query);
        $applyPaid($query);

        $counter = Db::name('fc_post')
            ->where('audit_status', 1)
            ->where('status', 1)
            ->whereNull('deletetime');
        $applyCategory($counter);
        if ($keyword !== '') {
            $counter->where('title', 'like', '%' . $keyword . '%');
        }
        $applyArea($counter);
        $applyPaid($counter);
        $total = $counter->count();

        if ($sort === 'nearby') {
            $rows = $query->order('createtime desc')->select();
            $items = [];
            foreach ($rows as $row) {
                $items[] = [
                    'item'     => $this->buildPost($row),
                    'distance' => $this->postDistance($row),
                    'ct'       => (int)$row['createtime'],
                ];
            }
            usort($items, function ($a, $b) {
                $na = $a['distance'] === null;
                $nb = $b['distance'] === null;
                if ($na !== $nb) {
                    return $na ? 1 : -1;
                }
                if (!$na && $a['distance'] != $b['distance']) {
                    return $a['distance'] < $b['distance'] ? -1 : 1;
                }
                return $b['ct'] - $a['ct'];
            });
            $list = [];
            foreach ($items as $it) {
                $list[] = $it['item'];
            }
            $this->ok($this->paginateArray($list, $page, $size));
        }

        if ($sort === 'price_desc') {
            $query->order('is_top desc, price desc');
        } elseif ($sort === 'price' || $sort === 'price_asc') {
            $query->order('is_top desc, price asc');
        } elseif ($sort === 'hot') {
            $query->order('is_top desc, views desc');
        } else {
            $query->order('is_top desc, createtime desc');
        }

        $rows = $query->page($page, $size)->select();

        $list = [];
        foreach ($rows as $row) {
            $list[] = $this->buildPost($row);
        }

        $this->ok($this->paginate($list, $total, $page, $size));
    }

    /**
     * Haversine 距离（km，一位小数）
     * @return float
     */
    protected function haversine($lat1, $lng1, $lat2, $lng2)
    {
        $earth = 6371.0;
        $rad = M_PI / 180;
        $dLat = ($lat2 - $lat1) * $rad;
        $dLng = ($lng2 - $lng1) * $rad;
        $a = sin($dLat / 2) * sin($dLat / 2)
            + cos($lat1 * $rad) * cos($lat2 * $rad) * sin($dLng / 2) * sin($dLng / 2);
        $c = 2 * asin(min(1.0, sqrt($a)));
        return round($earth * $c, 1);
    }

    /**
     * 列表项距离（km，一位小数；请求未带坐标 / 信息未定位 = null）
     * @param array $row fc_post 行
     * @return float|null
     */
    protected function postDistance($row)
    {
        $lat = $this->input('lat', null);
        $lng = $this->input('lng', null);
        if (!is_numeric($lat) || !is_numeric($lng)) {
            return null;
        }
        $lat = (float)$lat;
        $lng = (float)$lng;
        if ($lat == 0.0 && $lng == 0.0) {
            return null;
        }
        $plat = isset($row['lat']) && $row['lat'] !== null ? (float)$row['lat'] : 0.0;
        $plng = isset($row['lng']) && $row['lng'] !== null ? (float)$row['lng'] : 0.0;
        if ($plat == 0.0 && $plng == 0.0) {
            return null;
        }
        return $this->haversine($lat, $lng, $plat, $plng);
    }

    /**
     * 组装 Post 结构（含二级分类与农产品属性）
     * @param array $row fc_post 行
     * @return array
     */
    protected function buildPost($row)
    {
        $categoryName = '';
        if (!empty($row['category_id'])) {
            $cat = Db::name('fc_category')->where('id', $row['category_id'])->find();
            if ($cat) {
                $categoryName = (string)$cat['name'];
            }
        }

        $subCategoryId = isset($row['sub_category_id']) ? (int)$row['sub_category_id'] : 0;
        $subCategoryName = '';
        if ($subCategoryId > 0) {
            $subCat = Db::name('fc_category')->where('id', $subCategoryId)->find();
            if ($subCat) {
                $subCategoryName = (string)$subCat['name'];
            }
        }

        $publisher = ['id' => 0, 'name' => '', 'avatar' => '', 'isMerchant' => false, 'verified' => false];
        if (!empty($row['user_id'])) {
            $pub = Db::name('user')->where('id', $row['user_id'])->find();
            if ($pub) {
                $pubExt = Db::name('fc_user_ext')->where('user_id', $pub['id'])->find();
                $isMerchant = $pubExt && (int)$pubExt['user_type'] === 2;
                $publisher = [
                    'id'         => (int)$pub['id'],
                    'name'       => (string)$pub['nickname'],
                    'avatar'     => (string)$pub['avatar'],
                    'isMerchant' => (bool)$isMerchant,
                    'verified'   => (bool)$isMerchant,
                ];
            }
        }

        $tags = [];
        if (!empty($row['tags'])) {
            foreach (explode(',', (string)$row['tags']) as $tag) {
                $tag = trim($tag);
                if ($tag !== '') {
                    $tags[] = $tag;
                }
            }
        }

        return [
            'id'              => (int)$row['id'],
            'categoryId'      => (int)$row['category_id'],
            'categoryName'    => $categoryName,
            'subCategoryId'   => $subCategoryId,
            'subCategoryName' => $subCategoryName,
            'title'           => (string)$row['title'],
            'content'         => (string)$row['content'],
            'cover'           => (string)$row['cover'],
            'price'           => (float)$row['price'],
            'priceUnit'       => (string)$row['price_unit'],
            'province'        => isset($row['province']) ? (string)$row['province'] : '',
            'city'            => isset($row['city']) ? (string)$row['city'] : '',
            'area'            => (string)$row['area'],
            'areaId'          => (int)$row['district_id'],
            'address'         => (string)$row['address'],
            'plantArea'       => isset($row['plant_area']) ? (string)$row['plant_area'] : '',
            'harvestTime'     => isset($row['harvest_time']) ? (string)$row['harvest_time'] : '',
            'outputRange'     => isset($row['output_range']) ? (string)$row['output_range'] : '',
            'contact'         => $this->maskPhone($row['phone']),
            'views'           => (int)$row['views'],
            'likes'           => (int)$row['likes'],
            'isPaid'          => (int)$row['is_paid'] === 1,
            'isTop'           => (int)$row['is_top'] === 1,
            'auditStatus'     => (int)$row['audit_status'],
            'createdAt'       => $this->iso($row['createtime']),
            'tags'            => $tags,
            'publisher'       => $publisher,
            'commentCount'    => (int)$row['comment_count'],
            'distance'        => $this->postDistance($row),
        ];
    }

    /**
     * 全兼容分类图标/实拍图路径解析
     * @param int    $id      分类ID
     * @param string $iconKey 分类图标键名或图片路径
     * @param string $image   分类实拍图路径
     * @return string
     */
    protected function resolveCategoryIconPath($id, $iconKey = '', $image = '')
    {
        if ($image !== '' && preg_match('/^https?:\/\/|^\/uploads\/|^\/static\//i', $image)) {
            return $image;
        }
        if ($iconKey !== '') {
            if (preg_match('/^https?:\/\/|^\/uploads\/|^\/static\//i', $iconKey)) {
                return $iconKey;
            }
            $iconFileName = (strpos($iconKey, '.') !== false) ? $iconKey : $iconKey . '.png';
            if (file_exists(ROOT_PATH . 'public/static/categories/' . $iconFileName)) {
                return '/static/categories/' . $iconFileName;
            }
            if (file_exists(ROOT_PATH . 'public/static/icons/' . $iconFileName)) {
                return '/static/icons/' . $iconFileName;
            }
        }
        return '/static/categories/' . $this->iconFile($id);
    }

    /**
     * 分类 id → 默认图标文件名
     * @param int $id
     * @return string
     */
    protected function iconFile($id)
    {
        $map = [
            1 => 'cat-veg.png',
            2 => 'cat-fruit.png',
        ];
        return isset($map[$id]) ? $map[$id] : 'cat-veg.png';
    }
}