<?php

// +----------------------------------------------------------------------
// | ThinkPHP [ WE CAN DO IT JUST THINK ]
// +----------------------------------------------------------------------
// | Copyright (c) 2006~2025 http://thinkphp.cn All rights reserved.
// +----------------------------------------------------------------------
// | Licensed ( http://www.apache.org/licenses/LICENSE-2.0 )
// +----------------------------------------------------------------------
// | Author: liu21st <liu21st@gmail.com>
// +----------------------------------------------------------------------
declare (strict_types = 1);

namespace think\model\relation;

use Closure;
use think\Collection;
use think\db\BaseQuery as Query;
use think\helper\Str;
use think\model\contract\Modelable as Model;
use think\model\Relation;

/**
 * 一对多关联类.
 */
class HasMany extends Relation
{
    /**
     * 架构函数.
     *
     * @param Model  $parent     上级模型对象
     * @param string $model      模型名
     * @param string $foreignKey 关联外键
     * @param string $localKey   当前模型主键
     */
    public function __construct(Model $parent, string $model, string $foreignKey, string $localKey)
    {
        $this->parent     = $parent;
        $this->model      = $model;
        $this->foreignKey = $foreignKey;
        $this->localKey   = $localKey;
        $this->query      = (new $model())->getQuery();

        if (get_class($parent) == $model) {
            $this->selfRelation = true;
        }
    }

    /**
     * 延迟获取关联数据.
     *
     * @param array   $subRelation 子关联名
     * @param Closure $closure     闭包查询条件
     *
     * @return Collection
     */
    public function getRelation(array $subRelation = [], ?Closure $closure = null): Collection
    {
        if ($closure) {
            $closure($this->query);
        }

        return $this->query
            ->where($this->foreignKey, $this->parent->{$this->localKey})
            ->relation($subRelation)
            ->select();
    }

    /**
     * 预载入关联查询.
     *
     * @param array   $resultSet   数据集
     * @param string  $relation    当前关联名
     * @param array   $subRelation 子关联名
     * @param Closure $closure     闭包
     * @param array   $cache       关联缓存
     *
     * @return void
     */
    public function eagerlyResultSet(array &$resultSet, string $relation, array $subRelation, ?Closure $closure = null, array $cache = []): void
    {
        $localKey = $this->localKey;
        $range    = [];

        foreach ($resultSet as $result) {
            // 获取关联外键列表
            if (isset($result->$localKey)) {
                $range[] = $result->$localKey;
            }
        }

        if (!empty($range)) {
            $data = $this->eagerlyOneToMany([
                [$this->foreignKey, 'in', $range],
            ], $subRelation, $closure, $cache);

            // 关联数据封装
            foreach ($resultSet as $result) {
                $pk = $result->$localKey;
                if (!isset($data[$pk])) {
                    $data[$pk] = [];
                }

                $result->setRelation($relation, $this->resultSetBuild($data[$pk]));
            }
        }
    }

    /**
     * 预载入关联查询.
     *
     * @param Model   $result      数据对象
     * @param string  $relation    当前关联名
     * @param array   $subRelation 子关联名
     * @param Closure $closure     闭包
     * @param array   $cache       关联缓存
     *
     * @return void
     */
    public function eagerlyResult(Model $result, string $relation, array $subRelation = [], ?Closure $closure = null, array $cache = []): void
    {
        $localKey = $this->localKey;

        if (isset($result->$localKey)) {
            $pk   = $result->$localKey;
            $data = $this->eagerlyOneToMany([
                [$this->foreignKey, '=', $pk],
            ], $subRelation, $closure, $cache);

            // 关联数据封装
            if (!isset($data[$pk])) {
                $data[$pk] = [];
            }

            $result->setRelation($relation, $this->resultSetBuild($data[$pk]));
        }
    }

    /**
     * 关联统计
     *
     * @param Model   $result    数据对象
     * @param Closure $closure   闭包
     * @param string  $aggregate 聚合查询方法
     * @param string  $field     字段
     * @param string  $name      统计字段别名
     *
     * @return int
     */
    public function relationCount(Model $result, ?Closure $closure = null, string $aggregate = 'count', string $field = 'id',  ? string &$name = null)
    {
        $localKey = $this->localKey;

        if (!isset($result->$localKey)) {
            return 0;
        }

        if ($closure) {
            $closure($this->query, $name);
        }

        return $this->query
            ->where($this->foreignKey, '=', $result->$localKey)
            ->$aggregate($field);
    }

    /**
     * 创建关联统计子查询.
     *
     * @param Closure $closure   闭包
     * @param string  $aggregate 聚合查询方法
     * @param string  $field     字段
     * @param string  $name      统计字段别名
     *
     * @return string
     */
    public function getRelationCountQuery(?Closure $closure = null, string $aggregate = 'count', string $field = 'id',  ? string &$name = null) : string
    {
        if ($closure) {
            $closure($this->query, $name);
        }

        $alias = Str::snake(class_basename($this->model));
        $alias = $this->query->getAlias() ?: $alias . '_' . $aggregate;
        return $this->query->alias($alias)
            ->whereColumn($alias . '.' . $this->foreignKey, $this->parent->getTable(true) . '.' . $this->localKey)
            ->fetchSql()
            ->$aggregate($field);
    }

    /**
     * 一对多 关联模型预查询.
     *
     * @param array   $where       关联预查询条件
     * @param array   $subRelation 子关联
     * @param Closure $closure
     * @param array   $cache       关联缓存
     *
     * @return array
     */
    protected function eagerlyOneToMany(array $where, array $subRelation = [], ?Closure $closure = null, array $cache = []) : array
    {
        $foreignKey = $this->foreignKey;

        $this->query->removeWhereField($this->foreignKey);

        // 预载入关联查询 支持嵌套预载入
        if ($closure) {
            $this->baseQuery = true;
            $closure($this->query);
        }

        $withLimit = $this->query->getOptions('limit');
        if ($withLimit) {
            $this->query->removeOption('limit');
        }

        $list = $this->query
            ->where($where)
            ->cache($cache[0] ?? false, $cache[1] ?? null, $cache[2] ?? null)
            ->with($subRelation)
            ->select();

        // 组装模型数据
        $data = [];
        foreach ($list as $set) {
            $key = $set->$foreignKey;

            if ($withLimit && isset($data[$key]) && count($data[$key]) >= $withLimit) {
                continue;
            }

            $data[$key][] = $set;
        }

        return $data;
    }

    /**
     * 保存（新增）当前关联数据对象
     *
     * @param array|Model $data    数据 可以使用数组 关联模型对象
     * @param bool  $replace 是否自动识别更新和写入
     *
     * @return Model|false
     */
    public function save(array | Model $data, bool $replace = true)
    {
        $model = $this->make();

        return $model->replace($replace)->save($data) ? $model : false;
    }

    /**
     * 创建关联对象实例.
     *
     * @param array|Model $data
     *
     * @return Model
     */
    public function make(array | Model $data = []): Model
    {
        if ($data instanceof Model) {
            $data = $data->getData();
        }

        // 保存关联表数据
        $data[$this->foreignKey] = $this->parent->{$this->localKey};

        return (new $this->model($data))->setSuffix($this->getModel()->getSuffix());
    }

    /**
     * 批量保存当前关联数据对象
     *
     * @param iterable $dataSet 数据集
     * @param bool     $replace 是否自动识别更新和写入
     *
     * @return array|false
     */
    public function saveAll(iterable $dataSet, bool $replace = true)
    {
        $result = [];

        foreach ($dataSet as $key => $data) {
            $result[] = $this->save($data, $replace);
        }

        return empty($result) ? false : $result;
    }

    /**
     * 根据关联条件查询当前模型.
     *
     * @param string $operator 比较操作符
     * @param int    $count    个数
     * @param string $id       关联表的统计字段
     * @param string $joinType JOIN类型
     * @param Query  $query    Query对象
     *
     * @return Query
     */
    public function has(string $operator = '>=', int $count = 1, string $id = '*', string $joinType = 'INNER', ?Query $query = null): Query
    {
        $table    = $this->query->getTable();
        $model    = Str::snake(class_basename($this->parent));
        $query    = $query ?: $this->parent->getQuery();
        $alias    = $query->getAlias() ?: $model;

        return $query->alias($alias)
            ->whereExists(function ($query) use ($alias, $id, $table, $operator, $count) {
                $table      = $this->query->getTable();
                $relation   = Str::snake(class_basename($this->model));

                $query->table([$table => $relation])
                    ->field('count(' . $id . ') AS count')
                    ->whereColumn($relation . '.' . $this->foreignKey, $alias . '.' . $this->localKey)
                    ->having('count ' . $operator . ' ' . $count);

                $this->getRelationSoftDelete($query, $relation);
            });
    }

    /**
     * 根据关联条件查询当前模型.
     *
     * @param mixed  $where    查询条件（数组或者闭包）
     * @param mixed  $fields   字段
     * @param string $joinType JOIN类型
     * @param Query  $query    Query对象
     *
     * @return Query
     */
    public function hasWhere($where = [], $fields = null, string $joinType = '', ?Query $query = null, string $logic = ''): Query
    {
        $model    = Str::snake(class_basename($this->parent));
        $relation = Str::snake(class_basename($this->model));
        $table    = $this->query->getTable();
        $query    = $query ?: $this->parent->getQuery();
        $alias    = $query->getAlias() ?: $model;
        $fields   = $this->getRelationQueryFields($fields, $alias);

        $query->alias($alias)
            ->via($alias)
            ->group($alias . '.' . $this->localKey)
            ->field($fields)
            ->join([$table => $relation], $alias . '.' . $this->localKey . '=' . $relation . '.' . $this->foreignKey, $joinType);

        return $this->getRelationSoftDelete($query, $relation, $where, $logic);
    }

    /**
     * 执行基础查询（仅执行一次）.
     *
     * @return void
     */
    protected function baseQuery(): void
    {
        if (empty($this->baseQuery)) {
            if (isset($this->parent->{$this->localKey})) {
                // 关联查询带入关联条件
                $this->query->where($this->foreignKey, '=', $this->parent->{$this->localKey});
            }

            $this->baseQuery = true;
        }
    }
}
