/*
 *  R : A Computer Language for Statistical Data Analysis
 *  Copyright (C) 1995, 1996  Robert Gentleman and Ross Ihaka
 *  Copyright (C) 1998-2006   The R Development Core Team.
 *
 *  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., 51 Franklin Street Fifth Floor, Boston, MA 02110-1301  USA
 */

/* <UTF8> char here is either ASCII or handled as a whole */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "Defn.h"
#include "Print.h"

/* The global var. R_Expressions is in Defn.h */
#define R_MIN_EXPRESSIONS_OPT	25
#define R_MAX_EXPRESSIONS_OPT	500000

/* Interface to the (polymorphous!)  options(...)  command.
 *
 * We have two kind of options:
 *   1) those used exclusively from R code,
 *	typically initialized in Rprofile.

 *	Their names need not appear here, but may, when we want
 *	to make sure that they are assigned `valid' values only.
 *
 *   2) Those used (and sometimes set) from C code;
 *	Either accessing and/or setting a global C variable,
 *	or just accessed by e.g.  GetOption(install("pager"), ..)
 *
 * A (complete?!) list of these (2):
 *
 *	"prompt"
 *	"continue"
 *	"expressions"
 *	"width"
 *	"digits"
 *	"echo"
 *	"verbose"
 *	"keep.source"
 *	"keep.source.pkgs"

 *	"de.cellwidth"		../unix/X11/ & ../gnuwin32/dataentry.c
 *	"device"
 *	"pager"
 *	"paper.size"		./devPS.c

 *	"timeout"		./connections.c

 *	"check.bounds"
 *	"error"
 *	"error.messages"
 *	"show.error.messages"
 *	"warn"
 *	"warning.length"
 *	"warning.expression"

 *
 * S additionally/instead has (and one might think about some)
 * "free",	"keep"
 * "length",	"memory"
 * "object.size"
 * "reference", "show"
 * "scrap"
 */

static SEXP Options(void)
{
    return install(".Options");
}

static SEXP FindTaggedItem(SEXP lst, SEXP tag)
{
    for ( ; lst!=R_NilValue ; lst=CDR(lst)) {
	if (TAG(lst) == tag)
	    return lst;
    }
    return R_NilValue;
}

static SEXP makeErrorCall(SEXP fun)
{
  SEXP call;
  PROTECT(call = allocList(1));
  SET_TYPEOF(call, LANGSXP);
  SETCAR(call, fun);
  UNPROTECT(1);
  return call;
}

SEXP GetOption(SEXP tag, SEXP rho)
{
    SEXP opt = findVar(Options(), R_BaseEnv);
    if (!isList(opt))
	error(_("corrupted options list"));
    opt = FindTaggedItem(opt, tag);
    return CAR(opt);
}

int GetOptionWidth(SEXP rho)
{
    int w;
    w = asInteger(GetOption(install("width"), rho));
    if (w < R_MIN_WIDTH_OPT || w > R_MAX_WIDTH_OPT) {
	warning(_("invalid printing width, used 80"));
	return 80;
    }
    return w;
}

int GetOptionDigits(SEXP rho)
{
    int d;
    d = asInteger(GetOption(install("digits"), rho));
    if (d < R_MIN_DIGITS_OPT || d > R_MAX_DIGITS_OPT) {
	warning(_("invalid printing digits, used 7"));
	return 7;
    }
    return d;
}


int attribute_hidden Rf_GetOptionParAsk()
{
    int ask;
    ask = asLogical(GetOption(install("par.ask.default"), R_BaseEnv));
    if(ask == NA_LOGICAL) {
	warning(_("invalid par(\"par.ask.default\"), using FALSE"));
	return FALSE;
    }
   return ask != 0;
}


/* Change the value of an option or add a new option or, */
/* if called with value R_NilValue, remove that option. */

static SEXP SetOption(SEXP tag, SEXP value)
{
    SEXP opt, old, t;
    t = opt = SYMVALUE(Options());
    if (!isList(opt))
	error(_("corrupted options list"));
    opt = FindTaggedItem(opt, tag);

    /* The option is being removed. */
    if (value == R_NilValue) {
	for ( ; t != R_NilValue ; t = CDR(t))
	    if (TAG(CDR(t)) == tag) {
		old = CAR(t);
		SETCDR(t, CDDR(t));
		return old;
	    }
	return R_NilValue;
    }
    /* If the option is new, a new slot */
    /* is added to the end of .Options */
    if (opt == R_NilValue) {
	while (CDR(t) != R_NilValue)
	    t = CDR(t);
	PROTECT(value);
	SETCDR(t, allocList(1));
	UNPROTECT(1);
	opt = CDR(t);
	SET_TAG(opt, tag);
    }
    old = CAR(opt);
    SETCAR(opt, value);
    return old;
}

/* Set the width of lines for printing i.e. like options(width=...) */
/* Returns the previous value for the options. */

int R_SetOptionWidth(int w)
{
    SEXP t, v;
    if (w < R_MIN_WIDTH_OPT) w = R_MIN_WIDTH_OPT;
    if (w > R_MAX_WIDTH_OPT) w = R_MAX_WIDTH_OPT;
    PROTECT(t = install("width"));
    PROTECT(v = ScalarInteger(w));
    v = SetOption(t, v);
    UNPROTECT(2);
    return INTEGER(v)[0];
}

int R_SetOptionWarn(int w)
{
    SEXP t, v;

    t = install("warn");
    PROTECT(v = ScalarInteger(w));
    v = SetOption(t, v);
    UNPROTECT(1);
    return INTEGER(v)[0];
}

/* Note that options are stored as a dotted pair list */
/* This is barely historical, but is also useful. */

void attribute_hidden InitOptions(void)
{
    SEXP val, v;
    char *p;

    PROTECT(v = val = allocList(12));

    SET_TAG(v, install("prompt"));
    SETCAR(v, mkString("> "));
    v = CDR(v);

    SET_TAG(v, install("continue"));
    SETCAR(v, mkString("+ "));
    v = CDR(v);

    SET_TAG(v, install("expressions"));
    SETCAR(v, ScalarInteger(R_Expressions));
    v = CDR(v);

    SET_TAG(v, install("width"));
    SETCAR(v, ScalarInteger(80));
    v = CDR(v);

    SET_TAG(v, install("digits"));
    SETCAR(v, ScalarInteger(7));
    v = CDR(v);

    SET_TAG(v, install("echo"));
    SETCAR(v, allocVector(LGLSXP, 1));
    LOGICAL(CAR(v))[0] = !R_Slave;
    v = CDR(v);

    SET_TAG(v, install("verbose"));
    SETCAR(v, allocVector(LGLSXP, 1));
    LOGICAL(CAR(v))[0] = R_Verbose;
    v = CDR(v);

    SET_TAG(v, install("check.bounds"));
    SETCAR(v, allocVector(LGLSXP, 1));
    LOGICAL(CAR(v))[0] = 0;	/* no checking */
    v = CDR(v);

    p = getenv("R_KEEP_PKG_SOURCE");
    R_KeepSource = (p && (strcmp(p, "yes") == 0)) ? 1 : 0;

    SET_TAG(v, install("keep.source")); /* overridden in common.R */
    SETCAR(v, allocVector(LGLSXP, 1));
    LOGICAL(CAR(v))[0] = R_KeepSource;
    v = CDR(v);

    SET_TAG(v, install("keep.source.pkgs"));
    SETCAR(v, allocVector(LGLSXP, 1));
    LOGICAL(CAR(v))[0] = R_KeepSource;
    v = CDR(v);

    SET_TAG(v, install("warnings.length"));
    SETCAR(v, allocVector(INTSXP, 1));
    INTEGER(CAR(v))[0] = 1000;
    v = CDR(v);

    SET_TAG(v, install("OutDec"));
    SETCAR(v, allocVector(STRSXP, 1));
    SET_STRING_ELT(CAR(v), 0, mkChar("."));

    SET_SYMVALUE(install(".Options"), val);
    UNPROTECT(1);
}


SEXP attribute_hidden do_options(SEXP call, SEXP op, SEXP args, SEXP rho)
{
    SEXP argi= R_NilValue, argnames= R_NilValue, namei= R_NilValue,
	names, options, s, tag, value; /* = R_Nil..: -Wall */
    SEXP sind, names2, value2;
    int i, k, n, *indx;

    /* Locate the options values in the symbol table.
       This will need to change if options are to live in the session
       frame.
       */

    options = SYMVALUE(Options());

    if (args == R_NilValue) {
	/* This is the zero argument case.
	   We alloc up a real list and write the system values into it.
	*/
	n = length(options);
	PROTECT(value = allocVector(VECSXP, n));
	PROTECT(names = allocVector(STRSXP, n));
	i = 0;
	while (options != R_NilValue) {
	    SET_STRING_ELT(names, i, PRINTNAME(TAG(options)));
	    SET_VECTOR_ELT(value, i, duplicate(CAR(options)));
	    options = CDR(options); i++;
	}
	PROTECT(sind = allocVector(INTSXP, n));  indx = INTEGER(sind);
	for (i = 0; i < n; i++) indx[i] = i;
	orderVector1(indx, n, names, TRUE, FALSE);
	PROTECT(value2 = allocVector(VECSXP, n));
	PROTECT(names2 = allocVector(STRSXP, n));
	for(i = 0; i < n; i++) {
	    SET_STRING_ELT(names2, i, STRING_ELT(names, indx[i]));
	    SET_VECTOR_ELT(value2, i, VECTOR_ELT(value, indx[i]));
	}
	setAttrib(value2, R_NamesSymbol, names2);
	UNPROTECT(5);
	return value2;
    }

    /* The arguments to "options" can either be a sequence of
       name = value form, or can be a single list.
       This means that we must code so that both forms will work.
       [ Vomits quietly onto shoes ... ]
       */

    n = length(args);
    if (n == 1 && (isPairList(CAR(args)) || isVectorList(CAR(args)))
        && TAG(args) == R_NilValue ) {
	args = CAR(args);
	n = length(args);
    }
    PROTECT(value = allocVector(VECSXP, n));
    PROTECT(names = allocVector(STRSXP, n));

    switch (TYPEOF(args)) {
    case NILSXP:
    case LISTSXP:
	argnames = R_NilValue;
	break;
    case VECSXP:
	argnames = getAttrib(args, R_NamesSymbol);
	if(LENGTH(argnames) != n)
	    errorcall(call, _("list argument has no valid names"));
	break;
    default:
	UNIMPLEMENTED_TYPE("options", args);
    }

    R_Visible = 0;
    for (i = 0 ; i < n ; i++) { /* i-th argument */

	switch (TYPEOF(args)) {
	case LISTSXP:
	    argi = CAR(args);
	    namei = EnsureString(TAG(args));
	    args = CDR(args);
	    break;
	case VECSXP:
	    argi = VECTOR_ELT(args, i);
	    namei = EnsureString(STRING_ELT(argnames, i));
	    break;
	default: /* already checked, but be safe here */
	    UNIMPLEMENTED_TYPE("options", args);
	}

	if (*CHAR(namei)) { /* name = value  ---> assignment */
	    tag = install(CHAR(namei));
	    if (streql(CHAR(namei), "width")) {
		k = asInteger(argi);
		if (k < R_MIN_WIDTH_OPT || k > R_MAX_WIDTH_OPT)
		    errorcall(call,
			      _("invalid width parameter, allowed %d...%d"),
			      R_MIN_WIDTH_OPT, R_MAX_WIDTH_OPT);
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarInteger(k)));
	    }
	    else if (streql(CHAR(namei), "digits")) {
		k = asInteger(argi);
		if (k < R_MIN_DIGITS_OPT || k > R_MAX_DIGITS_OPT)
		    errorcall(call,
			      _("invalid digits parameter, allowed %d...%d"),
			      R_MIN_DIGITS_OPT, R_MAX_DIGITS_OPT);
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarInteger(k)));
	    }
	    else if (streql(CHAR(namei), "expressions")) {
		k = asInteger(argi);
		if (k < R_MIN_EXPRESSIONS_OPT || k > R_MAX_EXPRESSIONS_OPT)
		    errorcall(call,
			      _("expressions parameter invalid, allowed %d...%d"),
			      R_MIN_EXPRESSIONS_OPT, R_MAX_EXPRESSIONS_OPT);
		R_Expressions = R_Expressions_keep = k;
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarInteger(k)));
	    }
	    else if (streql(CHAR(namei), "keep.source")) {
		if (TYPEOF(argi) != LGLSXP || LENGTH(argi) != 1)
		    errorcall(call, _("keep.source parameter invalid"));
		k = asLogical(argi);
		R_KeepSource = k;
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarLogical(k)));
	    }
	    else if (streql(CHAR(namei), "editor")) {
		s = asChar(argi);
		if (s == NA_STRING || length(s) == 0)
		    errorcall(call, _("invalid editor parameter"));
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarString(s)));
	    }
	    else if (streql(CHAR(namei), "continue")) {
		s = asChar(argi);
		if (s == NA_STRING || length(s) == 0)
		    errorcall(call, _("invalid continue parameter"));
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarString(s)));
	    }
	    else if (streql(CHAR(namei), "prompt")) {
		s = asChar(argi);
		if (s == NA_STRING || length(s) == 0)
		    errorcall(call, _("prompt parameter invalid"));
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarString(s)));
	    }
	    else if (streql(CHAR(namei), "contrasts")) {
		if (TYPEOF(argi) != STRSXP || LENGTH(argi) != 2)
		    errorcall(call, _("contrasts parameter invalid"));
		SET_VECTOR_ELT(value, i, SetOption(tag, argi));
	    }
	    else if (streql(CHAR(namei), "check.bounds")) {
		if (TYPEOF(argi) != LGLSXP || LENGTH(argi) != 1)
		    errorcall(call, _("check.bounds parameter invalid"));
		k = asLogical(argi);
		/* R_CheckBounds = k; */
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarLogical(k)));
	    }
	    else if (streql(CHAR(namei), "warn")) {
		if (!isNumeric(argi) || length(argi) != 1)
		    errorcall(call, _("warn parameter invalid"));
                SET_VECTOR_ELT(value, i, SetOption(tag, argi));
	    }
	    else if (streql(CHAR(namei), "warning.length")) {
		k = asInteger(argi);
		if (k < 100 || k > 8192)
		    errorcall(call, _("warning.length parameter invalid"));
		R_WarnLength = k;
                SET_VECTOR_ELT(value, i, SetOption(tag, argi));
	    }
	    else if ( streql(CHAR(namei), "warning.expression") )  {
		if( !isLanguage(argi) &&  ! isExpression(argi) )
		    errorcall(call, _("warning.expression parameter invalid"));
		SET_VECTOR_ELT(value, i, SetOption(tag, argi));
	    }
	    else if ( streql(CHAR(namei), "error") ) {
	        if(isFunction(argi))
		  argi = makeErrorCall(argi);
	        else if( !isLanguage(argi) &&  !isExpression(argi) )
		    errorcall(call, _("error parameter invalid"));
		SET_VECTOR_ELT(value, i, SetOption(tag, argi));
	    }
/* handle this here to avoid GetOption during error handling */
	    else if ( streql(CHAR(namei), "show.error.messages") ) {
		if( !isLogical(argi) && length(argi) != 1 )
		    errorcall(call, _("show.error.messages parameter invalid"));
		SET_VECTOR_ELT(value, i, SetOption(tag, argi));
		R_ShowErrorMessages = LOGICAL(argi)[0];
	    }
	    else if (streql(CHAR(namei), "echo")) {
		if (TYPEOF(argi) != LGLSXP || LENGTH(argi) != 1)
		    errorcall(call, _("echo parameter invalid"));
		k = asLogical(argi);
		/* Should be quicker than checking options(echo)
		   every time R prompts for input:
		   */
		R_Slave = !k;
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarLogical(k)));
	    }
	    else if (streql(CHAR(namei), "OutDec")) {
		if (TYPEOF(argi) != STRSXP || LENGTH(argi) != 1 ||
		    strlen(CHAR(STRING_ELT(argi, 0))) !=1)
		    errorcall(call, _("OutDec parameter invalid"));
		OutDec = CHAR(STRING_ELT(argi, 0))[0];
		SET_VECTOR_ELT(value, i, SetOption(tag, duplicate(argi)));
	    }
	    else if (streql(CHAR(namei), "max.contour.segments")) {
		k = asInteger(argi);
		if (k < 0 || k  == NA_INTEGER)
		    errorcall(call,
			      _("max.contour.segment parameter invalid"));
		max_contour_segments = k;
		SET_VECTOR_ELT(value, i, SetOption(tag, ScalarInteger(k)));
	    }
	    else {
		SET_VECTOR_ELT(value, i, SetOption(tag, duplicate(argi)));
	    }
	    SET_STRING_ELT(names, i, namei);
	}
	else { /* querying arg */
	    if (!isString(argi) || LENGTH(argi) <= 0)
		errorcall(call, R_MSG_IA);
	    SET_VECTOR_ELT(value, i, duplicate(CAR(FindTaggedItem(options,
				     install(CHAR(STRING_ELT(argi, 0)))))));
	    SET_STRING_ELT(names, i, STRING_ELT(argi, 0));
	    R_Visible = 1;
	}
    } /* for() */
    setAttrib(value, R_NamesSymbol, names);
    UNPROTECT(2);
    return value;
}