#include	<string.h>
#include	<stdio.h>
#include        "gr.hh"
#include        "extern.hh"
#include        "private.hh"
#include        "Variable.hh"


static vector<GriVariable> variableStack;


// Make new variable
bool
create_variable(const char *name, double value)
{
    GriVariable newVariable(name, value);
    variableStack.push_back(newVariable);
    return true;
}

bool
show_variablesCmd()
{
    const int variables_per_line = 2; // how many columns?
    int             line_break = 0;
    bool            have_some = false;
    ShowStr("Variables...\n");
    vector<GriVariable>::iterator i;
    for (i = variableStack.begin(); i < variableStack.end(); i++) {
	extern char     _grTempString[];
	sprintf(_grTempString, "%25s=%-5g", i->getName(), i->getValue());
	ShowStr(_grTempString);
	if (!(++line_break % variables_per_line)) {
	    ShowStr("\n");
	} else {
	    ShowStr("  ");
	}
	have_some = true;
    }
    ShowStr("\n");
    if (!have_some) {
	ShowStr(" ... none exist\n");
    }
    return true;
}

// display unused user variables
void
display_unused_var()
{
    int i;
    unsigned stackLen = variableStack.size();
    extern char     _grTempString[];
    if (stackLen > 0) {
	char *name;
	for (i = stackLen - 1; i >= 0; i--) {
	    if (0 == variableStack[i].getCount()) {
		name = variableStack[i].getName();
		if (*(name + 1) != '.') { // avoid builtins
		    sprintf(_grTempString, "\
Warning: variable `%s' defined but not used\n", name);
		    ShowStr(_grTempString);
		}
	    }
	}
    }
}

// is_var - return 0 if not a variable, or 1 if is
bool
is_var(const char *w)
{
    int             len = strlen(w);
    return (len > 2 && w[0] == '.' && w[-1 + len] == '.' ? true : false);
}

// for internal debugging
void
show_var_stack()
{
    int i;
    unsigned stackLen = variableStack.size();
    if (stackLen > 0) {
	printf("Variable stack [\n");
	for (i = stackLen - 1; i >= 0; i--) {
	    printf("  %s = %f\n", 
		   variableStack[i].getName(),
		   variableStack[i].getValue());
	}
	printf("]\n");
    }
}

// Delete variable, searching from end of stack
bool
delete_var(const char *name)
{
    unsigned stackLen = variableStack.size();
    for (int i = stackLen - 1; i >= 0; i--) {
	if (!strcmp(name, variableStack[i].getName())) {
	    for (unsigned int j = i; j < stackLen - 1; j++)
		variableStack[j] = variableStack[j + 1];
	    variableStack.pop_back();
	    return true;
	}
    }
    return false;
}

// get_var() - get value of variable (incrementing the 'uses' flag)
// 
// RETURN true if variable is defined and has a value
// RETURN false otherwise
bool
get_var(const char *name, double *value)
{
    *value = 0.0;		// store something in case not found
    if (!is_var(name))
	return false;
    // Following are special cases.  They are not stored in the stack because
    // it would take far too much time.
    //
    // If more variables are added to this list, be sure to make changes to
    // gri.cc and extern.h, under comments which appear as follows:
    // 
    // The following globals have symbolic names associated with them, and
    // MUST be updated whenever these names are assigned to.  See the note in
    // put_var() in variable.c.  The reason for the parallel C storage is
    // that the following are accessed for every data point plotted. Certain
    // other symbolic variables (like ..publication.. for example) are not
    // accessed frequently, and hence have no parallel C storage as the
    // following do.  Thus they are safe against breakage.
    if (!strcmp(name, "..trace..")) {
	*value = (int) _griState.trace();
	return true;
    } else if (!strcmp(name, "..use_default_for_query..")) {
	*value = (int) _use_default_for_query;
	return true;
    } else if (!strcmp(name, "..linewidth..")) {
	*value = _griState.linewidth_line();
	return true;
    } else if (!strcmp(name, "..linewidthaxis..")) {
	*value = _griState.linewidth_axis();
	return true;
    } else if (!strcmp(name, "..linewidthsymbol..")) {
	*value = _griState.linewidth_symbol();
	return true;
    } else if (!strcmp(name, "..superuser..")) {
	*value = _griState.superuser();
	return true;
    } else {
	// Look it up in stack
	int             i;
	unsigned        stackLen = variableStack.size();
	if (stackLen > 0) {
	    for (i = stackLen - 1; i >= 0; i--) {
#ifdef DEBUG_VARIABLE
		printf("debug: check [%s] vs %d-th [%s]\n", name, i, variableStack[i].getName());
#endif
		if (!strcmp(name, variableStack[i].getName())) {
		    *value = variableStack[i].getValue();
		    variableStack[i].incrementCount(); // record the usage
		    return true;
		}
	    }
	}
    }
    return false;
}

// put_var() -- assign value to name, creating new variable if necessary.
// If replace_existing=0 replace existing value.
// If replace_existing=1 create a new variable with the old name.
// RETURN NULL if can't do it.
bool
put_var(const char *name, double value, bool replace_existing)
{
    void            reset_top_of_plot(void);
    int             i;
    unsigned        stackLen = variableStack.size();
    // put_var (): Certain special cases are stored in C variables too,
    // for speed. (An example is ..xleft.., which is stored as _xleft and
    // used all over the code.)  Capture these and store the values. Also,
    // some operations should be intercepted for general use later: e.g.
    // changing ..ymargin.. requires calling reset_top_of_plot(). Note
    // that this code fragment is easy to break, because addition of new
    // internals means addition of code here.  See also the note in gri.cc,
    // where the internals are segmented.
    if (!strcmp(name, "..trace..")) {
	_griState.set_trace((floor(0.5 + value)) ? true : false);
    } else if (!strcmp(name, "..use_default_for_query..")) {
	_use_default_for_query = int(floor(0.5 + value)) ? true : false;
    } else if (!strcmp(name, "..linewidth..")) {
	_griState.set_linewidth_line(value);
    } else if (!strcmp(name, "..linewidthaxis..")) {
	_griState.set_linewidth_axis(value);
    } else if (!strcmp(name, "..linewidthsymbol..")) {
	_griState.set_linewidth_symbol(value);
    } else if (!strcmp(name, "..superuser.."))
	_griState.set_superuser(int(floor(0.5 + value)));
    else if (!strcmp(name, "..xleft.."))
	_xleft = value;
    else if (!strcmp(name, "..xright.."))
	_xright = value;
    else if (!strcmp(name, "..ybottom.."))
	_ybottom = value;
    else if (!strcmp(name, "..ytop.."))
	_ytop = value;
    // Replace if on stack already.
    if (replace_existing) {
	if (stackLen) {
	    for (i = stackLen - 1; i >= 0; i--) {
		if (!strcmp(name, variableStack[i].getName())) {
		    variableStack[i].setValue(value);
		    return true;
		}
	    }
	}
    }
    // Store on end of stack.
    GriVariable     newVariable(name, value);
    variableStack.push_back(newVariable);
    if (!strcmp(name, "..ymargin..") || !strcmp(name, "..ysize.."))
	reset_top_of_plot();
    return true;
}