/*
 *	aegis - project change supervisor
 *	Copyright (C) 1994-1996, 1999, 2002, 2003 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 mul expressions
 */

#include <ac/math.h>

#include <aer/expr/mul.h>
#include <aer/value/error.h>
#include <aer/value/integer.h>
#include <aer/value/real.h>
#include <error.h>
#include <sub.h>
#include <trace.h>

#define PAIR(a, b)	((a) * rpt_value_type_MAX + (b))


static rpt_value_ty *
mul_evaluate(rpt_expr_ty *this_thing)
{
    sub_context_ty  *scp;
    rpt_value_ty    *v1;
    rpt_value_ty    *v1a;
    rpt_value_ty    *v2;
    rpt_value_ty    *v2a;
    rpt_value_ty    *vp;
    string_ty       *s;

    /*
     * evaluate the left hand side
     */
    trace(("mul::evaluate()\n{\n"));
    assert(this_thing->nchild == 2);
    v1 = rpt_expr_evaluate(this_thing->child[0], 1);
    if (v1->method->type == rpt_value_type_error)
    {
	trace(("}\n"));
	return v1;
    }

    /*
     * coerce the left hand side to an arithmetic type
     * (will not give error if can't, will copy instead)
     */
    v1a = rpt_value_arithmetic(v1);
    rpt_value_free(v1);

    /*
     * evaluate the right hand side
     */
    v2 = rpt_expr_evaluate(this_thing->child[1], 1);
    if (v2->method->type == rpt_value_type_error)
    {
	rpt_value_free(v1a);
	trace(("}\n"));
	return v2;
    }

    /*
     * coerce the right hand side to an arithmetic type
     * (will not give error if can't, will copy instead)
     */
    v2a = rpt_value_arithmetic(v2);
    rpt_value_free(v2);

    /*
     * the type of the result depends on
     * the types of the operands
     */
    switch (PAIR(v1a->method->type, v2a->method->type))
    {
    case PAIR(rpt_value_type_real, rpt_value_type_real):
	vp =
	    rpt_value_real
	    (
	       	rpt_value_real_query(v1a) * rpt_value_real_query(v2a)
	    );
	trace(("vp = %g real\n", rpt_value_real_query(vp)));
	break;

    case PAIR(rpt_value_type_real, rpt_value_type_integer):
	vp =
	    rpt_value_real
	    (
	       	rpt_value_real_query(v1a) * rpt_value_integer_query(v2a)
	    );
	trace(("vp = %g real\n", rpt_value_real_query(vp)));
	break;

    case PAIR(rpt_value_type_integer, rpt_value_type_real):
	vp =
	    rpt_value_real
	    (
	       	rpt_value_integer_query(v1a) * rpt_value_real_query(v2a)
	    );
	trace(("vp = %g real\n", rpt_value_real_query(vp)));
	break;

    case PAIR(rpt_value_type_integer, rpt_value_type_integer):
	vp =
	    rpt_value_integer
	    (
	       	rpt_value_integer_query(v1a) * rpt_value_integer_query(v2a)
	    );
	trace(("vp = %ld integer\n", rpt_value_integer_query(vp)));
	break;

    default:
	scp = sub_context_new();
	sub_var_set_charstar(scp, "Name1", v1a->method->name);
	sub_var_set_charstar(scp, "Name2", v2a->method->name);
	s = subst_intl(scp, i18n("illegal multiplication ($name1 * $name2)"));
	sub_context_delete(scp);
	vp = rpt_value_error(this_thing->pos, s);
	str_free(s);
	break;
    }
    rpt_value_free(v1a);
    rpt_value_free(v2a);
    trace(("return %08lX;\n", (long)vp));
    trace(("}\n"));
    return vp;
}


static rpt_expr_method_ty mul_method =
{
    sizeof(rpt_expr_ty),
    "mul",
    0, /* construct */
    0, /* destruct */
    mul_evaluate,
    0, /* lvalue */
};


rpt_expr_ty *
rpt_expr_mul(rpt_expr_ty *a, rpt_expr_ty *b)
{
    rpt_expr_ty     *this_thing;

    this_thing = rpt_expr_alloc(&mul_method);
    rpt_expr_append(this_thing, a);
    rpt_expr_append(this_thing, b);
    return this_thing;
}


static rpt_value_ty *
div_evaluate(rpt_expr_ty *this_thing)
{
    sub_context_ty  *scp;
    rpt_value_ty    *v1;
    rpt_value_ty    *v1a;
    rpt_value_ty    *v2;
    rpt_value_ty    *v2a;
    double	    den;
    long	    lden;
    rpt_value_ty    *result;
    string_ty	    *s;

    /*
     * evaluate the left hand side
     */
    trace(("div::evaluate()\n{\n"));
    assert(this_thing->nchild == 2);
    v1 = rpt_expr_evaluate(this_thing->child[0], 1);
    if (v1->method->type == rpt_value_type_error)
    {
	trace(("}\n"));
	return v1;
    }

    /*
     * coerce the left hand side to an arithmetic type
     * (will not give error if can't, will copy instead)
     */
    v1a = rpt_value_arithmetic(v1);
    rpt_value_free(v1);

    /*
     * evaluate the right hand side
     */
    v2 = rpt_expr_evaluate(this_thing->child[1], 1);
    if (v2->method->type == rpt_value_type_error)
    {
	rpt_value_free(v1a);
	trace(("}\n"));
	return v2;
    }

    /*
     * coerce the right hand side to an arithmetic type
     * (will not give error if can't, will copy instead)
     */
    v2a = rpt_value_arithmetic(v2);
    rpt_value_free(v2);

    /*
     * the type of the result depends on
     * the types of the operands
     */
    switch (PAIR(v1a->method->type, v2a->method->type))
    {
    case PAIR(rpt_value_type_real, rpt_value_type_real):
	den = rpt_value_real_query(v2a);
	if (den == 0)
	{
	    div_by_zero:
	    scp = sub_context_new();
	    s = subst_intl(scp, i18n("division by zero"));
	    sub_context_delete(scp);
	    result = rpt_value_error(this_thing->child[1]->pos, s);
	    str_free(s);
	    break;
	}
	result = rpt_value_real(rpt_value_real_query(v1a) / den);
	trace(("result = %g real\n", rpt_value_real_query(result)));
	break;

    case PAIR(rpt_value_type_real, rpt_value_type_integer):
	lden = rpt_value_integer_query(v2a);
	if (lden == 0)
	    goto div_by_zero;
	result = rpt_value_real(rpt_value_real_query(v1a) / lden);
	trace(("result = %g real\n", rpt_value_real_query(result)));
	break;

    case PAIR(rpt_value_type_integer, rpt_value_type_real):
	den = rpt_value_real_query(v2a);
	if (den == 0)
	    goto div_by_zero;
	result = rpt_value_real(rpt_value_integer_query(v1a) / den);
	trace(("result = %g real\n", rpt_value_real_query(result)));
	break;

    case PAIR(rpt_value_type_integer, rpt_value_type_integer):
	lden = rpt_value_integer_query(v2a);
	if (lden == 0)
	    goto div_by_zero;
	result = rpt_value_integer(rpt_value_integer_query(v1a) / lden);
	trace(("result = %ld integer\n",
	    rpt_value_integer_query(result)));
	break;

    default:
	scp = sub_context_new();
	sub_var_set_charstar(scp, "Name1", v1a->method->name);
	sub_var_set_charstar(scp, "Name2", v2a->method->name);
	s = subst_intl(scp, i18n("illegal division ($name1 / $name2)"));
	sub_context_delete(scp);
	result = rpt_value_error(this_thing->pos, s);
	str_free(s);
	break;
    }
    rpt_value_free(v1a);
    rpt_value_free(v2a);
    trace(("return %08lX;\n", (long)result));
    trace(("}\n"));
    return result;
}


static rpt_expr_method_ty div_method =
{
    sizeof(rpt_expr_ty),
    "div",
    0, /* construct */
    0, /* destruct */
    div_evaluate,
    0, /* lvalue */
};


rpt_expr_ty *
rpt_expr_div(rpt_expr_ty *a, rpt_expr_ty *b)
{
    rpt_expr_ty     *this_thing;

    this_thing = rpt_expr_alloc(&div_method);
    rpt_expr_append(this_thing, a);
    rpt_expr_append(this_thing, b);
    return this_thing;
}


static rpt_value_ty *
mod_evaluate(rpt_expr_ty *this_thing)
{
    sub_context_ty  *scp;
    rpt_value_ty    *v1;
    rpt_value_ty    *v1a;
    rpt_value_ty    *v2;
    rpt_value_ty    *v2a;
    double	    den;
    long	    lden;
    rpt_value_ty    *result;
    string_ty       *s;

    /*
     * evaluate the left hand side
     */
    trace(("mod::evaluate()\n{\n"));
    assert(this_thing->nchild == 2);
    v1 = rpt_expr_evaluate(this_thing->child[0], 1);
    if (v1->method->type == rpt_value_type_error)
    {
	trace(("}\n"));
	return v1;
    }

    /*
     * coerce the left hand side to an arithmetic type
     * (will not give error if can't, will copy instead)
     */
    v1a = rpt_value_arithmetic(v1);
    rpt_value_free(v1);

    /*
     * evaluate the right hand side
     */
    v2 = rpt_expr_evaluate(this_thing->child[1], 1);
    if (v2->method->type == rpt_value_type_error)
    {
	rpt_value_free(v1a);
	trace(("}\n"));
	return v2;
    }

    /*
     * coerce the right hand side to an arithmetic type
     * (will not give error if can't, will copy instead)
     */
    v2a = rpt_value_arithmetic(v2);
    rpt_value_free(v2);

    /*
     * the type of the result depends on
     * the types of the operands
     */
    switch (PAIR(v1a->method->type, v2a->method->type))
    {
    case PAIR(rpt_value_type_real, rpt_value_type_real):
	den = rpt_value_real_query(v2a);
	if (den == 0)
	{
	    mod_by_zero:
	    scp = sub_context_new();
	    s = subst_intl(scp, i18n("modulo by zero"));
	    sub_context_delete(scp);
	    result = rpt_value_error(this_thing->child[1]->pos, s);
	    str_free(s);
	    break;
	}
	result = rpt_value_real(fmod(rpt_value_real_query(v1a), den));
	trace(("result = %g real\n", rpt_value_real_query(result)));
	break;

    case PAIR(rpt_value_type_real, rpt_value_type_integer):
	den = rpt_value_integer_query(v2a);
	if (den == 0)
	    goto mod_by_zero;
	result = rpt_value_real(fmod(rpt_value_real_query(v1a), den));
	trace(("result = %g real\n", rpt_value_real_query(result)));
	break;

    case PAIR(rpt_value_type_integer, rpt_value_type_real):
	den = rpt_value_real_query(v2a);
	if (den == 0)
	    goto mod_by_zero;
	result =
	    rpt_value_real
	    (
	       	fmod((double)rpt_value_integer_query(v1a), den)
	    );
	trace(("result = %g real\n", rpt_value_real_query(result)));
	break;

    case PAIR(rpt_value_type_integer, rpt_value_type_integer):
	lden = rpt_value_integer_query(v2a);
	if (lden == 0)
	    goto mod_by_zero;
	result = rpt_value_integer(rpt_value_integer_query(v1a) % lden);
	trace(("result = %ld integer\n", rpt_value_integer_query(result)));
	break;

    default:
	scp = sub_context_new();
	sub_var_set_charstar(scp, "Name1", v1a->method->name);
	sub_var_set_charstar(scp, "Name2", v2a->method->name);
	/* xgettext:no-c-format */
	s = subst_intl(scp, i18n("illegal modulo ($name1 %% $name2)"));
	sub_context_delete(scp);
	result = rpt_value_error(this_thing->pos, s);
	str_free(s);
	break;
    }
    rpt_value_free(v1a);
    rpt_value_free(v2a);
    trace(("return %08lX;\n", (long)result));
    trace(("}\n"));
    return result;
}


static rpt_expr_method_ty mod_method =
{
    sizeof(rpt_expr_ty),
    "mod",
    0, /* construct */
    0, /* destruct */
    mod_evaluate,
    0, /* lvalue */
};


rpt_expr_ty *
rpt_expr_mod(rpt_expr_ty *a, rpt_expr_ty *b)
{
    rpt_expr_ty     *this_thing;

    this_thing = rpt_expr_alloc(&mod_method);
    rpt_expr_append(this_thing, a);
    rpt_expr_append(this_thing, b);
    return this_thing;
}
