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table.join bug fix  [bad limit check]

/** @file
	Parser: @b table parser class.

	Copyright (c) 2001, 2003 ArtLebedev Group (http://www.artlebedev.com)
	Author: Alexandr Petrosian <paf@design.ru> (http://paf.design.ru)
*/

static const char* IDENT_TABLE_C="$Date: 2003/04/25 12:32:31 $";

#include "classes.h"
#include "pa_common.h"
#include "pa_request.h"
#include "pa_vtable.h"
#include "pa_vint.h"
#include "pa_sql_connection.h"
#include "pa_vbool.h"

// class

class MTable : public Methoded {
public: // VStateless_class
	Value *create_new_value(Pool& pool) { return new(pool) VTable(pool); }

public:
	MTable(Pool& pool);

public: // Methoded
	bool used_directly() { return true; }
};

// methods

static Table::Action_options get_action_options(Request& r, 
				     const String& method_name, MethodParams *params, 
				     const Table& source) {
	Table::Action_options result;

	if(!params->size())
		return result;

	Hash* options=params->get(params->size()-1).get_hash(&method_name);
	if(!options)
		return result;

	result.defined=true;
	bool defined_offset=false;

	int valid_options=0;
	if(Value *voffset=(Value *)options->get(*sql_offset_name)) {
		valid_options++;
		defined_offset=true;
		if(voffset->is_string()) {
			const String& soffset=*voffset->get_string();
			if(soffset == "cur")
				result.offset=source.current();
			else
				throw Exception("parser.runtime",
					&soffset,
					"must be 'cur' string or expression");
		} else 
			result.offset=r.process_to_value(*voffset).as_int();
	}
	if(Value *vlimit=(Value *)options->get(*sql_limit_name)) {
		valid_options++;
		result.limit=r.process_to_value(*vlimit).as_int();
	}
	if(Value *vreverse=(Value *)options->get(*table_reverse_name)) {
		valid_options++;
		result.reverse=r.process_to_value(*vreverse).as_bool();
		if(result.reverse && !defined_offset)
			result.offset=source.size()-1;
	}
	if(valid_options!=options->size())
		throw Exception("parser.runtime",
			&method_name,
			"called with invalid option");

	return result;
}
static void check_option_param(bool options_defined, 
			  const String& method_name, MethodParams *params, 
			  int next_param_index,
			  const char *msg) {
	if(next_param_index+(options_defined?1:0) != params->size())
		throw Exception("parser.runtime",
			&method_name,
			"%s", msg);
}

static void _create(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();
	// clone/copy part?
	if(const Table *source=params->get(0).get_table()) {
		Table::Action_options o=get_action_options(r, method_name, params, *source);
		check_option_param(o.defined, method_name, params, 1, 
			"too many parameters");
		static_cast<VTable *>(r.get_self())->
			set_table(*new(pool) Table(pool, *source, o));
		return;
	}

	// data is last parameter
	Temp_lang temp_lang(r, String::UL_PASS_APPENDED);
	const String& data=
		r.process_to_string(params->as_junction(params->size()-1, "body must be code"));

	size_t pos_after=0;
	// parse columns
	Array *columns;
	if(params->size()==2) {
		columns=0;
	} else {
		columns=new(pool) Array(pool);

		Array head(pool);
		data.split(head, &pos_after, "\n", 1, String::UL_AS_IS, 1);
		if(head.size())
			head.get_string(0)->split(*columns, 0, "\t", 1, String::UL_AS_IS);
	}

	Table& table=*new(pool) Table(pool, &method_name, columns);
	// parse cells
	Array rows(pool);
	data.split(rows, &pos_after, "\n", 1, String::UL_AS_IS);
	Array_iter i(rows);
	while(i.has_next()) {
		Array& row=*new(pool) Array(pool);
		const String& string=*i.next_string();
		// remove comment lines
		if(!string.size())
			continue;

		string.split(row, 0, "\t", 1, String::UL_AS_IS);
		table+=&row;
	}

	// replace any previous table value
	static_cast<VTable *>(r.get_self())->set_table(table);
}

static void _load(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();
	const String& first_param=params->as_string(0, "file name must be string");
	int filename_param_index=0;
	bool nameless=first_param=="nameless";
	if(nameless)
		filename_param_index++;
	int options_param_index=filename_param_index+1;
	
	// loading text
	char *data=file_read_text(pool, 
		r.absolute(params->as_string(filename_param_index, "file name must be string")),
		true,
		options_param_index<params->size()?params->as_no_junction(options_param_index, "additional params must be hash").get_hash(&method_name):0
	);

	// parse columns
	Array *columns;
#ifndef NO_STRING_ORIGIN
	const Origin& origin=method_name.origin();
	const char *file=origin.file;
	uint line=origin.line;
#endif
	if(nameless) {
		columns=0; // nameless
	} else {
		columns=new(pool) Array(pool);

		while(char *row_chars=getrow(&data)) {
			// remove empty&comment lines
			if(!*row_chars || *row_chars == '#')
				continue;
			do {
				String *name=new(pool) String(pool);
				name->APPEND_TAINTED(lsplit(&row_chars, '\t'), 0, file, line++);
				*columns+=name;
			} while(row_chars);

			break;
		}
	}

	// parse cells
	Table& table=*new(pool) Table(pool, &method_name, columns);
	char *row_chars;
	while(row_chars=getrow(&data)) {
		// remove empty&comment lines
		if(!*row_chars || *row_chars == '#')
			continue;
		Array *row=new(pool) Array(pool);
		while(char *cell_chars=lsplit(&row_chars, '\t')) {
			String *cell=new(pool) String(pool);
			cell->APPEND_TAINTED(cell_chars, 0, file, line);
			*row+=cell;
		}
#ifndef NO_STRING_ORIGIN
		line++;
#endif
		table+=row;
	};

	// replace any previous table value
	static_cast<VTable *>(r.get_self())->set_table(table);
}

/// @todo "x\nx" "xxx""xx"
static void _save(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();
	Value& vfile_name=params->as_no_junction(params->size()-1, 
		"file name must not be code");

	Table& table=static_cast<VTable *>(r.get_self())->table(&method_name);

	bool do_append=false;
	String sdata(pool);
	if(params->size()==1) { // named output
		// write out names line
		if(table.columns()) { // named table
			Array_iter i(*table.columns());
			while(i.has_next()) {
				sdata.append(*i.next_string(), //*static_cast<String *>(table.columns()->quick_get(column)), 
					String::UL_TABLE);
				if(i.has_next())
					sdata.APPEND_CONST("\t");
			}
		} else { // nameless table
			if(int lsize=table.size()?static_cast<Array *>(table.get(0))->size():0)
				for(int column=0; column<lsize; column++) {
					char *cindex_tab=(char *)pool.malloc(MAX_NUMBER);
					snprintf(cindex_tab, MAX_NUMBER, "%d\t", column);
					sdata.APPEND_CONST(cindex_tab);
				}
			else
				sdata.APPEND_CONST("empty nameless table");
		}
		sdata.APPEND_CONST("\n");
	} else { // mode specified
		const String& mode=params->as_string(0, "mode must be string");
		if(mode=="append")
			do_append=true;
		else if(mode=="nameless")
			/*ok, already skipped names output*/;
		else
			throw Exception("parser.runtime",
				&mode,
				"unknown mode, must be 'append'");

	}
	// data lines
	Array_iter i(table);
	while(i.has_next()) {
		Array_iter c(*static_cast<Array *>(i.next()));
		while(c.has_next()) {
			if(const String *s=c.next_string())
				sdata.append(*s,
					String::UL_TABLE);
			if(c.has_next())
				sdata.APPEND_CONST("\t");
		}
		sdata.APPEND_CONST("\n");
	}

	// write
	file_write(r.absolute(vfile_name.as_string()), 
		sdata.cstr(), sdata.size(), true, do_append);
}

static void _count(Request& r, const String& method_name, MethodParams *) {
	Pool& pool=r.pool();
	int result=static_cast<VTable *>(r.get_self())->table(&method_name).size();
	r.write_no_lang(*new(pool) VInt(pool, result));
}

static void _line(Request& r, const String& method_name, MethodParams *) {
	Pool& pool=r.pool();
	int result=1+static_cast<VTable *>(r.get_self())->table(&method_name).current();
	r.write_no_lang(*new(pool) VInt(pool, result));
}

static void _offset(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();
	Table& table=static_cast<VTable *>(r.get_self())->table(&method_name);
	if(params->size()) {
		bool absolute=false;
		if(params->size()>1) {
		    const String& whence=params->as_string(0, "whence must be string");
		    if(whence=="cur")
				absolute=false;
		    else if(whence=="set")
				absolute=true;
		    else
				throw Exception("parser.runtime",
					&whence,
					"is invalid whence, valid are 'cur' or 'set'");
		}
		
		Value& offset_expr=params->as_junction(params->size()-1, "offset must be expression");
		table.offset(absolute, r.process_to_value(offset_expr).as_int());
	} else
		r.write_no_lang(*new(pool) VInt(pool, table.current()));
}

static void _menu(Request& r, const String& method_name, MethodParams *params) {
	Value& body_code=params->as_junction(0, "body must be code");
	
	Value *delim_maybe_code=params->size()>1?&params->get(1):0;

	Table& table=static_cast<VTable *>(r.get_self())->table(&method_name);
	bool need_delim=false;
	int saved_current=table.current();
	int size=table.size();
	for(int row=0; row<size; row++) {
		table.set_current(row);

		StringOrValue sv_processed=r.process(body_code);
		const String *s_processed=sv_processed.get_string();
		if(delim_maybe_code && s_processed && s_processed->size()) { // delimiter set and we have body
			if(need_delim) // need delim & iteration produced string?
				r.write_pass_lang(r.process(*delim_maybe_code));
			need_delim=true;
		}
		r.write_pass_lang(sv_processed);
	}
	table.set_current(saved_current);
}

#ifndef DOXYGEN
enum Table2hash_distint { D_ILLEGAL, D_FIRST, D_TABLES };
struct Row_info {
	Request *r;
	Table *table;
	Value *key_code;
	int key_field;
	Array *value_fields;
	Hash *hash;
	Table2hash_distint distinct;
	int row;
};
#endif
static void table_row_to_hash(Array::Item *value, void *info) {
	Array& row=*static_cast<Array *>(value);
	Row_info& ri=*static_cast<Row_info *>(info);
	Pool& pool=ri.table->pool();

	const String *key;
	if(ri.key_code) {
		ri.table->set_current(ri.row++); // change context row
		StringOrValue sv_processed=ri.r->process(*ri.key_code);
		key=&sv_processed.as_string();
	} else
		key=ri.key_field<row.size()?row.get_string(ri.key_field):0;

	if(!key)
		return; // ignore rows without key [too-short-record_array if-indexed]
		
	switch(ri.distinct) {
	case D_ILLEGAL: case D_FIRST:
		{
			VHash& result=*new(pool) VHash(pool);
			Hash& hash=*result.get_hash(0);
			for(int i=0; i<ri.value_fields->size(); i++) {
				int value_field=ri.value_fields->get_int(i);
				if(value_field<row.size())
					hash.put(
						*ri.table->columns()->get_string(value_field), 
						new(pool) VString(*row.get_string(value_field)));
			}

			if(ri.hash->put_dont_replace(*key, &result)) // put. existed?
				if(ri.distinct==D_ILLEGAL)
					throw Exception("parser.runtime",
						key,
						"duplicate key");
		}
		break;
	case D_TABLES:
		{
			VTable* vtable=(VTable*)ri.hash->get(*key); // put. table existed?
			Table* table;
			if(vtable) 
				table=vtable->get_table();
			else {
				// no? creating table of same structure as source
				Table::Action_options table_options(0, 0);
				table=new(pool) Table(pool, *ri.table, table_options/*no rows, just structure*/);
				ri.hash->put(*key, new(pool) VTable(pool, table));
			}
			*table+=&row;
		}
		break;
	default:
		throw Exception(0,
			0,
			"invalid distinct code (#%d)", ri.distinct);
	}

}
static void _hash(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();
	Table& self_table=static_cast<VTable *>(r.get_self())->table(&method_name);
	Value& result=*new(pool) VHash(pool);
	if(const Array *columns=self_table.columns())
		if(columns->size()>0) {
			Table2hash_distint distinct=D_ILLEGAL;
			int param_index=params->size()-1;
			if(param_index>0) {
				if(Hash *options=
					params->as_no_junction(param_index, "param must not be code").get_hash(0)) {
					--param_index;
					int valid_options=0;
					if(Value *vdistinct_code=(Value *)options->get(*sql_distinct_name)) {
						valid_options++;
						Value& vdistinct_value=r.process_to_value(*vdistinct_code);
						if(vdistinct_value.is_string()) {
							const String& sdistinct=*vdistinct_value.get_string();
							if(sdistinct=="tables")
								distinct=D_TABLES;
							else
								throw Exception("parser.runtime",
									&sdistinct,
									"must be 'tables' or true/false");
						} else
							distinct=vdistinct_value.as_bool()?D_FIRST:D_ILLEGAL;
					}
					if(valid_options!=options->size())
						throw Exception("parser.runtime",
							&method_name,
							"called with invalid option");
				}
			}
			if(param_index==2) // bad options param type
				throw Exception("parser.runtime",
					&method_name,
					"options must be hash");

			Array value_fields(pool);
			if(param_index>0) {
				if(distinct!=D_ILLEGAL && distinct!=D_FIRST)
					throw Exception("parser.runtime",
						0,
						"in distinct[tables] mode you may not specify value field(s)");
				Value& value_fields_param=params->as_no_junction(param_index, "value field(s) must not be code");
				if(value_fields_param.is_string()) {
					value_fields+=self_table.column_name2index(value_fields_param.as_string(), true);
				} else if(Table *value_fields_table=value_fields_param.get_table()) {
					for(int i=0; i<value_fields_table->size(); i++) {
						const String& value_field_name=
							*static_cast<Array *>(value_fields_table->get(i))->get_string(0);
						value_fields+=self_table.column_name2index(value_field_name, true);
					}
				} else
					throw Exception("parser.runtime",
						&method_name,
						"value field(s) must be string or self_table"
					);
			} else { // by all columns, including key
				if(!(distinct!=D_ILLEGAL && distinct!=D_FIRST))
					for(int i=0; i<columns->size(); i++)
						value_fields+=i;
			}

			Value& key_param=params->get(0);
			Value *key_code=key_param.get_junction()?&key_param:0;
			int key_field=key_code?-1
				:self_table.column_name2index(key_param.as_string(), true);

			Row_info row_info={&r, &self_table, 
				key_code, key_field, &value_fields, 
				result.get_hash(0), distinct};

			int saved_current=self_table.current();
			self_table.for_each(table_row_to_hash, &row_info);
			self_table.set_current(saved_current);
		}
	r.write_no_lang(result);
}

#ifndef DOXYGEN
struct Table_seq_item {
	Array *row;
	union {
		char *c_str;
		double d;
	} value;
};
#endif
static int sort_cmp_string(const void *a, const void *b) {
	return strcmp(
		static_cast<const Table_seq_item *>(a)->value.c_str, 
		static_cast<const Table_seq_item *>(b)->value.c_str
	);
}
static int sort_cmp_double(const void *a, const void *b) {
	double va=static_cast<const Table_seq_item *>(a)->value.d;
	double vb=static_cast<const Table_seq_item *>(b)->value.d;
	if(va<vb)
		return -1;
	else if(va>vb)
		return +1;
	else 
		return 0;
}
static void _sort(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();
	Value& key_maker=params->as_junction(0, "key-maker must be code");

	bool reverse=params->size()>1/*..[desc|asc|]*/?
		reverse=params->as_no_junction(1, "order must not be code").as_string()=="desc":
		false; // default=asc

	Table& old_table=static_cast<VTable *>(r.get_self())->table(&method_name);
	if(old_table.size()==0)
		return;

	Table& new_table=*new(pool) Table(pool, &method_name, old_table.columns());

	Table_seq_item *seq=(Table_seq_item *)pool.malloc(sizeof(Table_seq_item)*old_table.size());
	int i;

	// calculate key values
	bool key_values_are_strings=true;
	for(i=0; i<old_table.size(); i++) {
		old_table.set_current(i);
		// calculate key value
		seq[i].row=(MethodParams *)old_table.get(i);
		Value& value=*r.process_to_value(key_maker).as_expr_result(true/*return string as-is*/);
		if(i==0) // determining key values type by first one
			key_values_are_strings=value.is_string();

		if(key_values_are_strings)
			seq[i].value.c_str=value.as_string().cstr();
		else
			seq[i].value.d=value.as_double();
	}
	// sort keys
	_qsort(seq, old_table.size(), sizeof(Table_seq_item), 
		key_values_are_strings?sort_cmp_string:sort_cmp_double);

	// reorder table as they require in 'seq'
	for(i=0; i<old_table.size(); i++)
		new_table+=seq[reverse?old_table.size()-1-i:i].row;

	// replace any previous table value
	static_cast<VTable *>(r.get_self())->set_table(new_table);
}

#ifndef DOXYGEN
struct Locate_expression_func_info {
	Request* r;
	Value* expression_code;
};
#endif
bool locate_expression_func(Table& self, void* ainfo) {
	Locate_expression_func_info& info=*static_cast<Locate_expression_func_info*>(ainfo);
	return info.r->process_to_value(*info.expression_code).as_bool();
}
static bool _locate_expression(Table& table, Table::Action_options o,
			       Request& r, const String& method_name, MethodParams *params) {
	check_option_param(o.defined, method_name, params, 1,
		"locate by expression only has parameters: expression and, maybe, options");
	Value& expression_code=params->as_junction(0, "must be expression");

	Locate_expression_func_info info={&r, &expression_code};
	return table.locate(locate_expression_func, &info, o);
}
static bool _locate_name_value(Table& table, Table::Action_options o,
			       Request& r, const String& method_name, MethodParams *params) {
	check_option_param(o.defined, method_name, params, 2,
		"locate by locate by name has parameters: name, value and, maybe, options");
	const String& name=params->as_string(0, "column name must be string");
	const String& value=params->as_string(1, "value must be string");

	return table.locate(name, value, o);
}
static void _locate(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();
	Table& table=static_cast<VTable *>(r.get_self())->table(&method_name);

	Table::Action_options o=get_action_options(r, method_name, params, table);

	bool result=params->get(0).get_junction()?
		_locate_expression(table, o, r, method_name, params) :
		_locate_name_value(table, o, r, method_name, params);
	r.write_no_lang(*new(pool) VBool(pool, result));
}

static void _flip(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();
	Table& old_table=static_cast<VTable *>(r.get_self())->table(&method_name);
	Table& new_table=*new(pool) Table(pool, &method_name, 0/*nameless*/);
	if(old_table.size())
		if(int old_cols=old_table.at(0).size()) 
			for(int column=0; column<old_cols; column++) {
				Array& new_row=*new(pool) Array(pool, old_table.size());
				for(int i=0; i<old_table.size(); i++) {
					const Array& old_row=old_table.at(i);
					new_row+=column<old_row.size()?old_row.get(column):new(pool) String(pool);
				}
				new_table+=&new_row;
			}

	r.write_no_lang(*new(pool) VTable(pool, &new_table));
}

static void _append(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();
	// data
	Temp_lang temp_lang(r, String::UL_PASS_APPENDED);
	const String& string=
		r.process_to_string(params->as_junction(0, "body must be code"));

	// parse cells
	Array& row=*new(pool) Array(pool);
	string.split(row, 0, "\t", 1, String::UL_AS_IS);

	static_cast<VTable *>(r.get_self())->table(&method_name)+=&row;
}

static void _join(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();

	Table* maybe_src=params->as_no_junction(0, "table ref must not be code").get_table();
	if(!maybe_src)
		throw Exception("parser.runtime", 
			&method_name, 
			"source is not a table");
	Table& src=*maybe_src;

	Table::Action_options o=get_action_options(r, method_name, params, src);
	check_option_param(o.defined, method_name, params, 1,
		"invalid extra parameter");

	Table& dest=static_cast<VTable *>(r.get_self())->table(&method_name);
	if(&src == &dest)
		throw Exception("parser.runtime", 
			&method_name, 
			"source and destination are same table");

	if(o.reverse)
		throw Exception(0,
			&method_name,
			"not implemented in this version, please upgrade");
	if(const Array *dest_columns=dest.columns()) { // dest is named
		int saved_src_current=src.current();
		int m=src.size()-o.offset;
		if(o.limit<0 || o.limit>m)
			o.limit=m;
		int end=o.offset+o.limit;
		for(int src_row=o.offset; src_row<end; src_row++) {
			src.set_current(src_row);
			Array& dest_row=*new(pool) Array(pool);
			for(int dest_column=0; dest_column<dest_columns->size(); dest_column++) {
				const String *src_item=src.item(*dest_columns->get_string(dest_column));
				dest_row+=src_item?src_item:new(pool) String(pool);
			}
			dest+=&dest_row;
		}
		src.set_current(saved_src_current);
	} else { // dest is nameless
		for(int src_row=0; src_row<src.size(); src_row++)
			dest+=&src.at(src_row);
	}
}

#ifndef DOXYGEN
class Table_sql_event_handlers: public SQL_Driver_query_event_handlers {
public:
	Table_sql_event_handlers(Pool& apool, const String& amethod_name,
		const String& astatement_string, const char *astatement_cstr) :
		pool(apool), 
		method_name(amethod_name),
		statement_string(astatement_string),
		statement_cstr(astatement_cstr),
		columns(*new(pool) Array(pool)),
		row(0), 
		table(0)
	{
	}

	bool add_column(SQL_Error& error, void *ptr, size_t size) {
		try {
			String *column=new(pool) String(pool);
			column->APPEND_TAINTED(
				(const char *)ptr, size, 
				statement_cstr, 0);
			columns+=column;
			return false;
		} catch(...) {
			error=SQL_Error("exception occured in Table_sql_event_handlers::add_column");
			return true;
		}
	}
	bool before_rows(SQL_Error& error) { 
		try {
			table=new(pool) Table(pool, &method_name, &columns);
			return false;
		} catch(...) {
			error=SQL_Error("exception occured in Table_sql_event_handlers::before_rows");
			return true;
		}
	}
	bool add_row(SQL_Error& error) {
		try {
			(*table)+=(row=new(pool) Array(pool));
			return false;
		} catch(...) {
			error=SQL_Error("exception occured in Table_sql_event_handlers::add_row");
			return true;
		}
	}
	bool add_row_cell(SQL_Error& error, void *ptr, size_t size) {
		try {
			String *cell=new(pool) String(pool);
			if(size)
				cell->APPEND_TAINTED(
					(const char *)ptr, size, 
					statement_cstr, table->size()-1);
			(*row)+=cell;
			return false;
		} catch(...) {
			error=SQL_Error("exception occured in Table_sql_event_handlers::add_row_cell");
			return true;
		}
	}

private:
	Pool& pool;
	const String& method_name;
	const String& statement_string; const char *statement_cstr;
	Array& columns;
	Array *row;
public:
	Table *table;
};
#endif
static void _sql(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();

	Value& statement=params->as_junction(0, "statement must be code");

	ulong limit=0;
	ulong offset=0;
	if(params->size()>1) {
		Value& voptions=params->as_no_junction(1, "options must be hash, not code");
		if(!voptions.is_string())
			if(Hash *options=voptions.get_hash(&method_name)) {
				int valid_options=0;
				if(Value *vlimit=(Value *)options->get(*sql_limit_name)) {
					valid_options++;
					limit=(ulong)r.process_to_value(*vlimit).as_double();
				}
				if(Value *voffset=(Value *)options->get(*sql_offset_name)) {
					valid_options++;
					offset=(ulong)r.process_to_value(*voffset).as_double();
				}
				if(valid_options!=options->size())
					throw Exception("parser.runtime",
						&method_name,
						"called with invalid option");
			} else
				throw Exception("parser.runtime",
					&method_name,
					"options must be hash");
	}

	Temp_lang temp_lang(r, String::UL_SQL);
	const String& statement_string=r.process_to_string(statement);
	const char *statement_cstr=
		statement_string.cstr(String::UL_UNSPECIFIED, r.connection(&method_name));
	Table_sql_event_handlers handlers(pool, method_name,
		statement_string, statement_cstr);
#ifdef RESOURCES_DEBUG
	struct timeval mt[2];
	//measure:before
	gettimeofday(&mt[0],NULL);
#endif	
	r.connection(&method_name)->query(
		statement_cstr, offset, limit, 
		handlers,
		statement_string);
	
#ifdef RESOURCES_DEBUG
		//measure:after connect
	gettimeofday(&mt[1],NULL);
	
	double t[2];
	for(int i=0;i<2;i++)
	    t[i]=mt[i].tv_sec+mt[i].tv_usec/1000000.0;
	    
	r.sql_request_time+=t[1]-t[0];
#endif	    			

	Table *result=
		handlers.table?handlers.table: // query resulted in table? return it
		new(pool) Table(pool, &method_name, 0); // query returned no table, fake it

	// replace any previous table value
	static_cast<VTable *>(r.get_self())->set_table(*result);
}

static void _columns(Request& r, const String& method_name, MethodParams *) {
	Pool& pool=r.pool();

	Array& result_columns=*new(pool) Array(pool);
	result_columns+=new(pool) String(pool, "column");
	Table& result_table=*new(pool) Table(pool, &method_name, &result_columns);

	Table& source_table=static_cast<VTable *>(r.get_self())->table(&method_name);
	if(const Array *source_columns=source_table.columns()) {
		Array_iter i(*source_columns);
		while(i.has_next()) {
			Array& result_row=*new(pool) Array(pool);
			result_row+=i.next();
			result_table+=&result_row;
		}
	}

	r.write_no_lang(*new(pool) VTable(pool, &result_table));
}

static void _select(Request& r, const String& method_name, MethodParams *params) {
	Pool& pool=r.pool();

	Value& vcondition=params->as_junction(0, "condition must be expression");

	Table& source_table=static_cast<VTable *>(r.get_self())->table(&method_name);
	Table& result_table=*new(pool) Table(pool, 
		source_table.origin_string(), 
		source_table.columns()
	);

	int saved_current=source_table.current();
	int size=source_table.size();
	for(int row=0; row<size; row++) {
		source_table.set_current(row);

		bool condition=r.process_to_value(vcondition, 
				/*0/*no name* /,*/
				false/*don't intercept string*/).as_bool();

		if(condition) // ...condition is true=
			result_table+=&source_table.at(row); // =green light to go to result
	}
	source_table.set_current(saved_current);

	r.write_no_lang(*new(pool) VTable(pool, &result_table));
}

// constructor

MTable::MTable(Pool& apool) : Methoded(apool, "table") {
	// ^table::create{data}
	// ^table::create[nameless]{data}
	// ^table::create[table]
	add_native_method("create", Method::CT_DYNAMIC, _create, 1, 2);
	// old name for compatibility with <= v 1.141 2002/01/25 11:33:45 paf
	add_native_method("set", Method::CT_DYNAMIC, _create, 1, 2); 

	// ^table::load[file]  
	// ^table::load[nameless;file]
	add_native_method("load", Method::CT_DYNAMIC, _load, 1, 3);

	// ^table.save[file]  
	// ^table.save[nameless;file]
	add_native_method("save", Method::CT_DYNAMIC, _save, 1, 2);

	// ^table.count[]
	add_native_method("count", Method::CT_DYNAMIC, _count, 0, 0);

	// ^table.line[]
	add_native_method("line", Method::CT_DYNAMIC, _line, 0, 0);

	// ^table.offset[]  
	// ^table.offset(offset)
	// ^table.offset[cur|set](offset)
	add_native_method("offset", Method::CT_DYNAMIC, _offset, 0, 2);

	// ^table.menu{code}  
	// ^table.menu{code}[delim]
	add_native_method("menu", Method::CT_DYNAMIC, _menu, 1, 2);

	// ^table:hash[key field name]
	// ^table:hash[key field name][value field name(s) string/table]
	add_native_method("hash", Method::CT_DYNAMIC, _hash, 1, 3);

	// ^table.sort{string-key-maker} ^table.sort{string-key-maker}[desc|asc]
	// ^table.sort(numeric-key-maker) ^table.sort(numeric-key-maker)[desc|asc]
	add_native_method("sort", Method::CT_DYNAMIC, _sort, 1, 2);

	// ^table.locate[field;value]
	add_native_method("locate", Method::CT_DYNAMIC, _locate, 1, 3);

	// ^table.flip[]
	add_native_method("flip", Method::CT_DYNAMIC, _flip, 0, 0);

	// ^table.append{r{tab}e{tab}c{tab}o{tab}r{tab}d}
	add_native_method("append", Method::CT_DYNAMIC, _append, 1, 1);

	// ^table.join[table][$.limit(10) $.offset(1) $.offset[cur] ]
	add_native_method("join", Method::CT_DYNAMIC, _join, 1, 2);


	// ^table:sql[query]
	// ^table:sql[query][$.limit(1) $.offset(2)]
	add_native_method("sql", Method::CT_DYNAMIC, _sql, 1, 2);

	// ^table:columns[]
	add_native_method("columns", Method::CT_DYNAMIC, _columns, 0, 0);

	// ^table.select(expression) = table
	add_native_method("select", Method::CT_DYNAMIC, _select, 1, 1);
}

// global variable

Methoded *table_class;

// creator

Methoded *MTable_create(Pool& pool) {
	return table_class=new(pool) MTable(pool);
}