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/*
 * Copyright (c) 2011-2022, baomidou ([email protected]).
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.baomidou.mybatisplus.extension.plugins.pagination;

import com.baomidou.mybatisplus.core.metadata.IPage;
import com.baomidou.mybatisplus.core.metadata.OrderItem;
import lombok.Setter;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.function.Predicate;

/**
 * 简单分页模型
 *
 * @author hubin
 * @since 2018-06-09
 */
public class Page implements IPage {

    private static final long serialVersionUID = 8545996863226528798L;

    /**
     * 查询数据列表
     */
    protected List records = Collections.emptyList();

    /**
     * 总数
     */
    protected long total = 0;
    /**
     * 每页显示条数，默认 10
     */
    protected long size = 10;

    /**
     * 当前页
     */
    protected long current = 1;

    /**
     * 排序字段信息
     */
    @Setter
    protected List orders = new ArrayList<>();

    /**
     * 自动优化 COUNT SQL
     */
    protected boolean optimizeCountSql = true;
    /**
     * 是否进行 count 查询
     */
    protected boolean searchCount = true;
    /**
     * {@link #optimizeJoinOfCountSql()}
     */
    @Setter
    protected boolean optimizeJoinOfCountSql = true;
    /**
     * countId
     */
    @Setter
    protected String countId;
    /**
     * countId
     */
    @Setter
    protected Long maxLimit;

    public Page() {
    }

    /**
     * 分页构造函数
     *
     * @param current 当前页
     * @param size    每页显示条数
     */
    public Page(long current, long size) {
        this(current, size, 0);
    }

    public Page(long current, long size, long total) {
        this(current, size, total, true);
    }

    public Page(long current, long size, boolean searchCount) {
        this(current, size, 0, searchCount);
    }

    public Page(long current, long size, long total, boolean searchCount) {
        if (current > 1) {
            this.current = current;
        }
        this.size = size;
        this.total = total;
        this.searchCount = searchCount;
    }

    /**
     * 是否存在上一页
     *
     * @return true / false
     */
    public boolean hasPrevious() {
        return this.current > 1;
    }

    /**
     * 是否存在下一页
     *
     * @return true / false
     */
    public boolean hasNext() {
        return this.current < this.getPages();
    }

    @Override
    public List getRecords() {
        return this.records;
    }

    @Override
    public Page setRecords(List records) {
        this.records = records;
        return this;
    }

    @Override
    public long getTotal() {
        return this.total;
    }

    @Override
    public Page setTotal(long total) {
        this.total = total;
        return this;
    }

    @Override
    public long getSize() {
        return this.size;
    }

    @Override
    public Page setSize(long size) {
        this.size = size;
        return this;
    }

    @Override
    public long getCurrent() {
        return this.current;
    }

    @Override
    public Page setCurrent(long current) {
        this.current = current;
        return this;
    }

    @Override
    public String countId() {
        return this.countId;
    }

    @Override
    public Long maxLimit() {
        return this.maxLimit;
    }

    /**
     * 查找 order 中正序排序的字段数组
     *
     * @param filter 过滤器
     * @return 返回正序排列的字段数组
     */
    private String[] mapOrderToArray(Predicate filter) {
        List columns = new ArrayList<>(orders.size());
        orders.forEach(i -> {
            if (filter.test(i)) {
                columns.add(i.getColumn());
            }
        });
        return columns.toArray(new String[0]);
    }

    /**
     * 移除符合条件的条件
     *
     * @param filter 条件判断
     */
    private void removeOrder(Predicate filter) {
        for (int i = orders.size() - 1; i >= 0; i--) {
            if (filter.test(orders.get(i))) {
                orders.remove(i);
            }
        }
    }

    /**
     * 添加新的排序条件，构造条件可以使用工厂：{@link OrderItem#build(String, boolean)}
     *
     * @param items 条件
     * @return 返回分页参数本身
     */
    public Page addOrder(OrderItem... items) {
        orders.addAll(Arrays.asList(items));
        return this;
    }

    /**
     * 添加新的排序条件，构造条件可以使用工厂：{@link OrderItem#build(String, boolean)}
     *
     * @param items 条件
     * @return 返回分页参数本身
     */
    public Page addOrder(List items) {
        orders.addAll(items);
        return this;
    }

    @Override
    public List orders() {
        return this.orders;
    }

    @Override
    public boolean optimizeCountSql() {
        return optimizeCountSql;
    }

    public static  Page of(long current, long size, long total, boolean searchCount) {
        return new Page<>(current, size, total, searchCount);
    }

    @Override
    public boolean optimizeJoinOfCountSql() {
        return optimizeJoinOfCountSql;
    }

    public Page setSearchCount(boolean searchCount) {
        this.searchCount = searchCount;
        return this;
    }

    public Page setOptimizeCountSql(boolean optimizeCountSql) {
        this.optimizeCountSql = optimizeCountSql;
        return this;
    }

    @Override
    public long getPages() {
        // 解决 github issues/3208
        return IPage.super.getPages();
    }

    /* --------------- 以下为静态构造方式 --------------- */
    public static  Page of(long current, long size) {
        return of(current, size, 0);
    }

    public static  Page of(long current, long size, long total) {
        return of(current, size, total, true);
    }

    public static  Page of(long current, long size, boolean searchCount) {
        return of(current, size, 0, searchCount);
    }

    @Override
    public boolean searchCount() {
        if (total < 0) {
            return false;
        }
        return searchCount;
    }

    /**
     * --begin------------- 未来抛弃移除的方法 -------------begin--
     * 该部分属性转移至 {@link PageDTO}
     */
    @Deprecated
    public String getCountId() {
        return this.countId;
    }

    @Deprecated
    public Long getMaxLimit() {
        return this.maxLimit;
    }

    @Deprecated
    public List getOrders() {
        return this.orders;
    }

    @Deprecated
    public boolean isOptimizeCountSql() {
        return this.optimizeCountSql;
    }

    @Deprecated
    public boolean isSearchCount() {
        return this.searchCount;
    }
    /** --end------------- 未来抛弃移除的方法 -------------end-- */

}