/*
 *	cook - file construction tool
 *	Copyright (C) 1997, 1998 Peter Miller;
 *	All rights reserved.
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License as published by
 *	the Free Software Foundation; either version 2 of the License, or
 *	(at your option) any later version.
 *
 *	This program is distributed in the hope that it will be useful,
 *	but WITHOUT ANY WARRANTY; without even the implied warranty of
 *	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *	GNU General Public License for more details.
 *
 *	You should have received a copy of the GNU General Public License
 *	along with this program; if not, write to the Free Software
 *	Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
 *
 * MANIFEST: functions to manipulate unsetenv opcodes
 */

#include <ac/stdio.h>

#include <env.h>
#include <error_intl.h>
#include <expr/position.h>
#include <opcode/context.h>
#include <opcode/private.h>
#include <opcode/unsetenv.h>
#include <quote.h>
#include <str_list.h>
#include <trace.h>


typedef struct opcode_unsetenv_ty opcode_unsetenv_ty;
struct opcode_unsetenv_ty
{
	opcode_ty	inherited;
	expr_position_ty pos;
};


/*
 * NAME
 *	destructor
 *
 * SYNOPSIS
 *	void destructor(opcode_ty *);
 *
 * DESCRIPTION
 *	The destructor function is used to release resources held by
 *	this opcode.  Do not free the opcode itself, this is done by the
 *	base class.
 */

static void destructor _((opcode_ty *));

static void
destructor(op)
	opcode_ty	*op;
{
	opcode_unsetenv_ty *this;

	trace(("opcode_unsetenv::destructor()\n{\n"/*}*/));
	this = (opcode_unsetenv_ty *)op;
	expr_position_destructor(&this->pos);
	trace((/*{*/"}\n"));
}


/*
 * NAME
 *	execute
 *
 * SYNOPSIS
 *	opcode_status_ty execute(opcode_ty *, opcode_context_ty *);
 *
 * DESCRIPTION
 *	The execute function is used to execute the given opcode within
 *	the given interpretation context.
 *
 * RETURNS
 *	opcode_status_ty to indicate the result of the execution
 */

static opcode_status_ty execute _((const opcode_ty *, opcode_context_ty *));

static opcode_status_ty
execute(op, icp)
	const opcode_ty	*op;
	opcode_context_ty *icp;
{
	const opcode_unsetenv_ty *this;
	opcode_status_ty status;
	string_list_ty	*slp;
	size_t		j;

	trace(("opcode_unsetenv::execute()\n{\n"/*}*/));
	this = (const opcode_unsetenv_ty *)op;
	status = opcode_status_success;
	slp = opcode_context_string_list_pop(icp);
	if (!slp->nstrings)
	{
		error_with_position
		(
			&this->pos,
			0,
			i18n("unsetenv was given no words")
		);
		status = opcode_status_error;
	}
	for (j = 0; j < slp->nstrings; ++j)
		env_unset(slp->string[j]->str_text);
	string_list_delete(slp);
	trace(("return %s;\n", opcode_status_name(status)));
	trace((/*{*/"}\n"));
	return status;
}


/*
 * NAME
 *	script
 *
 * SYNOPSIS
 *	opcode_status_ty script(opcode_ty *, opcode_context_ty *);
 *
 * DESCRIPTION
 *	The script function is used to script the given opcode within
 *	the given interpretation context.
 *
 * RETURNS
 *	opcode_status_ty to indicate the result
 */

static opcode_status_ty script _((const opcode_ty *, opcode_context_ty *));

static opcode_status_ty
script(op, icp)
	const opcode_ty	*op;
	opcode_context_ty *icp;
{
	const opcode_unsetenv_ty *this;
	opcode_status_ty status;
	string_list_ty	*slp;
	size_t		j;

	trace(("opcode_unsetenv::script()\n{\n"/*}*/));
	this = (const opcode_unsetenv_ty *)op;
	status = opcode_status_success;
	slp = opcode_context_string_list_pop(icp);
	if (!slp->nstrings)
	{
		error_with_position
		(
			&this->pos,
			0,
			i18n("unsetenv was given no words")
		);
		status = opcode_status_error;
	}
	for (j = 0; j < slp->nstrings; ++j)
	{
		string_ty	*s;

		s = quote(slp->string[j]);
		printf("unset %s\n", s->str_text);
		str_free(s);
	}
	string_list_delete(slp);
	trace(("return %s;\n", opcode_status_name(status)));
	trace((/*{*/"}\n"));
	return status;
}


/*
 * NAME
 *	disassemble
 *
 * SYNOPSIS
 *	void disassemble(opcode_ty *);
 *
 * DESCRIPTION
 *	The disassemble function is used to disassemble the copdode and
 *	its arguments onto the standard output.  Don't worry about the
 *	location or a trailing newline.
 */

static void disassemble _((const opcode_ty *));

static void
disassemble(op)
	const opcode_ty	*op;
{
	const opcode_unsetenv_ty *this;

	trace(("opcode_unsetenv::disassemle()\n{\n"/*}*/));
	this = (const opcode_unsetenv_ty *)op;
	if (this->pos.pos_name)
	{
		printf
		(
			"# %s:%d",
			this->pos.pos_name->str_text,
			this->pos.pos_line
		);
	}
	trace((/*{*/"}\n"));
}


/*
 * NAME
 *	method
 *
 * DESCRIPTION
 *	The method variable describes this class.
 *
 * CAVEAT
 *	This symbol is not exported from this file.
 */

static opcode_method_ty method =
{
	"unsetenv",
	sizeof(opcode_unsetenv_ty),
	destructor,
	execute,
	script,
	disassemble,
};


/*
 * NAME
 *	opcode_unsetenv_new
 *
 * SYNOPSIS
 *	opcode_ty *opcode_unsetenv_new(void);
 *
 * DESCRIPTION
 *	The opcode_unsetenv_new function is used to allocate a new
 *	instance of an unsetenv opcode.
 *
 * RETURNS
 *	opcode_ty *; use opcode_delete when you are finished with it.
 */

opcode_ty *
opcode_unsetenv_new(pp)
	expr_position_ty *pp;
{
	opcode_ty	*op;
	opcode_unsetenv_ty *this;

	trace(("opcode_unsetenv_new()\n{\n"/*}*/));
	op = opcode_new(&method);
	this = (opcode_unsetenv_ty *)op;
	expr_position_copy_constructor(&this->pos, pp);
	trace(("return %08lX;\n", (long)op));
	trace((/*{*/"}\n"));
	return op;
}