package net.tccn.dbq.fbean;

import net.tccn.meta.MetaKit;
import net.tccn.meta.MetaLink;
import net.tccn.meta.MetaService;
import net.tccn.meta.MetaTable;

import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.function.Predicate;

/**
 * Created by liangxianyou at 2018/12/24 15:49.
 */
public class ParseMysql implements Parser {

    private Predicate isEmpty = (x) -> {
        if (x == null)
            return true;
        if (x instanceof List)
            return ((List) x).isEmpty();
        if (x instanceof String)
            return ((String) x).isEmpty();
        if (x instanceof Map)
            return ((Map) x).isEmpty();
        if (x instanceof Collection)
            return ((Collection) x).isEmpty();
        return false;
    };

    @Override
    public String parse(FBean fBean) {
        MetaService metaService = MetaKit.metaService(fBean.getName());

        //基础属性
        MetaTable metaTable = metaService.getMetaTable();//基础元数据
        List<MetaLink> linkTables = metaService.getMetaLinks();//表关联条件
        Map<String, MetaTable> attachTable = metaService.getTables();//用到的关联表
        List<String> shows = metaService.getShows();//查询的属性

        //查询条件
        List<Filter> filters = fBean.getFilters();
        Limit limit = fBean.getLimit();
        List<Order> orders = fBean.getOrders();

        StringBuilder buf = new StringBuilder();
        //select
        buf.append("select ");
        if (!isEmpty.test(shows)) {
            shows.forEach(x -> {
                //buf.append("`").append("x").append("`").append(",");
                buf.append(x).append(",");
            });
            buf.deleteCharAt(buf.length() - 1);
        } else {
            buf.append("*");
        }

        //from
        buf.append(" from ").append("`").append(metaTable.getName()).append("` ").append(metaTable.getAlias());

        //left join
        if (!isEmpty.test(linkTables)) {
            linkTables.forEach(x -> {
                MetaTable leftTable = attachTable.get(metaTable.getAlias().equals(x.getTables()[0]) ? x.getTables()[1] : x.getTables()[0]);

                buf.append(" left join ").append(leftTable.getName()).append(" ").append(leftTable.getAlias()).append(" on ");
                int tag = buf.length();
                x.getLink().forEach((k,v) -> {
                    if (buf.length() > tag) {
                        buf.append(" and ");
                    }
                    buf.append(k).append("=").append(v);
                });
            });
        }

        //where
        if (!isEmpty.test(filters)) {
            buf.append(Filter.filter(filters, DbType.MYSQL));
        }

        //order by
        if (!isEmpty.test(orders)) {
            buf.append(" ").append(Order.order(orders, DbType.MYSQL));
        }

        //limit
        buf.append(" ").append(limit.limit());
        return buf.toString();
    }

    @Override
    public String parse(Filter filter) {
        return null;
    }

    @Override
    public String parseSave(MetaService ms, Map data) {
        String sqlTpl = "insert %s (%s) value (%s)";
        StringBuilder bufK = new StringBuilder();
        StringBuilder bufV = new StringBuilder();
        data.forEach((k,v) -> {
            if (v != null || !String.valueOf(v).isEmpty()) {
                bufK.append("`").append(k).append("`,");
                if (v instanceof Number) {
                    bufV.append(v).append(",");
                } else {
                    bufV.append("'").append(v).append("',");
                }
            }
        });
        bufK.deleteCharAt(bufK.length() - 1);
        bufV.deleteCharAt(bufV.length() - 1);
        return String.format(sqlTpl, ms.getMetaTable().getName(), bufK.toString(), bufV.toString());
    }
}