//
//  REngine.m
//  Rgui
//
//  Created by Simon Urbanek on Wed Dec 10 2003.
//  Copyright (c) 2003 __MyCompanyName__. All rights reserved.
//

#import "REngine.h"
#include <CoreFoundation/CoreFoundation.h>
#include <CoreFoundation/CFBundle.h>
#include <R.h>
#include <Rinternals.h>
#include <R_ext/Parse.h>

extern void (*ptr_R_Suicide)(char *);
extern void (*ptr_R_ShowMessage)();
extern int  (*ptr_R_ReadConsole)(char *, unsigned char *, int, int);
extern void (*ptr_R_WriteConsole)(char *, int);
extern void (*ptr_R_ResetConsole)();
extern void (*ptr_R_FlushConsole)();
extern void (*ptr_R_ClearerrConsole)();
extern Rboolean R_Interactive;
extern FILE* R_Outputfile;
extern FILE* R_Consolefile;

id RE_consoleReceiver=nil;

void RE_WriteConsole(char *buf, int len) {
    NSString *str=[NSString stringWithCString:buf length:len];
    if (RE_consoleReceiver!=nil)
        [RE_consoleReceiver consoleWrite: str];
}

static REngine* mainRengine=nil;

@implementation REngine
int state=0;

+ (REngine*) mainEngine
{
    if (mainRengine==nil)
        mainRengine=[[REngine alloc] init];
    return mainRengine;
}

- (REngine*) init
{
    char *Rargv[4], *c;
    CFBundleRef requestedBundle;
    CFURLRef rdir;
    CFStringRef rhome;
    char buf[512];
    
    // Look for a bundle using its identifier
    requestedBundle = CFBundleGetBundleWithIdentifier(CFSTR("org.r-project.R-framework") );
    if (!requestedBundle) return nil;
    rdir=CFBundleCopyBundleURL(requestedBundle); CFRelease(requestedBundle);
    rhome=CFURLCopyFileSystemPath(rdir,kCFURLPOSIXPathStyle); CFRelease(rdir);
    CFStringGetCString(rhome,buf,512,kCFStringEncodingUTF8); CFRelease(rhome);
    strcat(buf,"/Resources");
    printf("R_HOME: %s\n",buf);
    
    setenv("R_HOME",buf,1);
    strcat(buf,"/bin:"); /* add $_RHOME/bin to LD..PATH just in case something is linked w/o path */
    c=getenv("DYLD_LIBRARY_PATH");
    if (c) strcat(buf,c);
    setenv("DYLD_LIBRARY_PATH",buf,1);
    
    Rargv[0]="Rgui"; Rargv[1]="--vanilla"; Rargv[2]=0;
    printf("starting R ...\n");
    Rf_initialize_R(2, Rargv);
    printf("done.\n");
    state=1;
           
           ptr_R_WriteConsole = RE_WriteConsole;
           R_Interactive=-1;
           R_Outputfile=0;
           R_Consolefile=0;
    /*
    printf("wc.orig=%x\n",ptr_R_WriteConsole);
    ptr_R_WriteConsole = Rgui_WriteConsole;
    printf("wc.new=%x\n",ptr_R_WriteConsole);
    ptr_R_ShowMessage = Rgui_ShowMessage;
    (*ptr_R_ShowMessage)("Testing ShowMessage\n");
    setup_Rmainloop();
    */

    return self;
}

- (void) setupLoop
{
    if (state==0) [self init];
    if (state==1) {
        setup_Rmainloop();
        state=2;
    }
}

- (RSEXP*) parse: (NSString*) str
{
    return [self parse: str withParts: 1];
}

- (RSEXP*) parse: (NSString*) str withParts: (int) count
{
    ParseStatus ps;
    SEXP pstr, cv;

    if (state<2) [self setupLoop];
    PROTECT(cv=allocVector(STRSXP, 1));
    SET_VECTOR_ELT(cv, 0, mkChar([str cString]));    
    pstr=R_ParseVector(cv, count, &ps);
    UNPROTECT(1);
    printf("parse status: %d, SEXP: %x, type: %d\n",ps, pstr, TYPEOF(pstr));
    return [[RSEXP alloc] initWithSEXP: pstr];
}

- (RSEXP*) evaluateExpressions: (RSEXP*) expr
{
    SEXP es;
    int er=0;
    int i=0,l;

    /*
    printf("to eval: SEXP %x,length=%d, type=%d\n",[expr directSEXP], [expr length], [expr type]);
    es=R_tryEval([expr directSEXP], R_GlobalEnv, &er);

    printf("er=%d\n",er);
    return [[RSEXP alloc] initWithSEXP: es];
    */
    if ([expr type]==EXPRSXP) {
        printf("to eval: SEXP length=%d, type=%d\n",[expr length], [expr type]);
        l=[expr length];
        while (i<l) {
            es=R_tryEval([[expr elementAt:i] directSEXP], R_GlobalEnv, &er);
            printf("Eval result: %d [rt=%d]\n",er,TYPEOF(es));
            i++;
        }
    } else
        es=R_tryEval([expr directSEXP], R_GlobalEnv, &er);
    
    return [[RSEXP alloc] initWithSEXP: es];
}

- (RSEXP*) evaluateString: (NSString*) str
{
    RSEXP *ps;
    ps=[self parse: str];
    if (ps==nil || [ps type]==NILSXP) return nil;
    return [self evaluateExpressions: ps];
}

- (RSEXP*) evaluateString: (NSString*) str withParts: (int) count
{
    RSEXP *ps;
    ps=[self parse: str withParts: count];
    if (ps==nil || [ps type]==NILSXP) return nil;
    return [self evaluateExpressions: ps];
}

- (void) setConsoleRespondent: (id) cr
{
    RE_consoleReceiver=cr;
}

@end