#include "query.h"
#include <iostream>

using namespace std;


WhereClause::WhereClause(void):col(0){}
WhereClause::WhereClause(const int _c,const RowItem &_v):col(_c),value(_v){}


QueryResult::QueryResult(void):res(0){}
QueryResult::QueryResult(int _res):res(_res){}
QueryResult::QueryResult(int _res,const vector<Row> &_rows):res(_res),rows(_rows){}
QueryResult::QueryResult(int _res,const vector<Row> &_rows,const string &_m):res(_res),rows(_rows),msg(_m){}
QueryResult::QueryResult(int _res,const string &_m):res(_res),msg(_m){}


QueryResult Query::execute(map<string,Table> &tables){return QueryResult(-1);}


CreateQuery::CreateQuery(void):nc(0),header(NULL){}

void CreateQuery::setHeader(const ColHeader *hd){
	header=new ColHeader[nc];
	memcpy(header,hd,nc*sizeof(ColHeader));
}

QueryResult CreateQuery::execute(map<string,Table> &tables){
	if(nc==0)return QueryResult(0,"zero nc");
	if(header==NULL)return QueryResult(0,"null header");
	const map<string,Table>::const_iterator tit=tables.find(tablename);
	if(tit!=tables.cend())return QueryResult(0,"existing table");
	tables.emplace(piecewise_construct,
	               forward_as_tuple(tablename),
	               forward_as_tuple(tablename,nc,header));
	return QueryResult(1);
}


FindQuery::FindQuery(void):limit(-1),sort(0){};

QueryResult FindQuery::execute(map<string,Table> &tables){
	if(limit==0)return QueryResult(0,"zero limit");
	int i,j;
	const map<string,Table>::const_iterator tit=tables.find(tablename);
	if(tit==tables.cend())return QueryResult(0,"non-existent table");
	const Table &table=tit->second;

	for(i=0;i<(int)where.size();i++){
		if(where[i].col==0)break;
	}
	if(i!=(int)where.size()){
		const map<string,Row>::const_iterator rit=table.rows.find(serialise(table.header[0],where[i].value));
		if(rit==table.rows.cend())return QueryResult(0);
		const Row &row=rit->second;
		for(j=0;j<(int)where.size();j++){
			if(j==i)continue;
			const int col=where[j].col;
			if(riCompare(table.header[col],row.items[col],where[j].value)!=0)break;
		}
		if(j!=(int)where.size())return QueryResult(0);
		else return QueryResult(1,{row});
	}

	typedef map<string,Row>::const_iterator cit_t;

	cit_t end=table.rows.cend();
	QueryResult ret;
	for(cit_t it=table.rows.cbegin();it!=end;it++){
		//if(serialise(it->second.table->header[0],it->second.items[0])==key)
		//	ret.emplace_back(it->second);
		for(i=0;i<(int)where.size();i++){
			const int col=where[i].col;
			if(riCompare(table.header[col],it->second.items[col],where[i].value)!=0)break;
		}
		if(i==(int)where.size()){
			ret.res++;
			ret.rows.emplace_back(it->second);
			if(ret.res==limit)return ret;
		}
	}
	return ret;
}


InsertQuery::InsertQuery(const Row &_r):row(_r){}
InsertQuery::InsertQuery(Row &&_r):row(move(_r)){}

QueryResult InsertQuery::execute(map <string,Table> &tables){
	map<string,Table>::iterator tit=tables.find(tablename);
	if(tit==tables.end())return QueryResult(0,"non-existent table");
	Table &table=tit->second;

	if(table.nc!=row.nc)return QueryResult(0,"non-conformant row width");
	const string primkey=serialise(table.header[0],row.items[0]);
	const map<string,Row>::const_iterator rit=table.rows.find(primkey);
	if(rit!=table.rows.cend())return QueryResult(0,"existing primary key");
	table.rows.insert(make_pair(primkey,row));
	return QueryResult(1);
}