#include <tcl.h>
#include <tk.h>
#include <stdio.h>
#include <X11/Xlib.h>
#include <X11/Xutil.h>
#include <X11/X.h>
#include <time.h>
#include <sys/time.h>
#include <string.h>
#include <stdlib.h>

/* Variables globales */
static int width = 800;
static int height = 400;

static inline double get_time_ms(void) {
    struct timeval tv;
    gettimeofday(&tv, NULL);
    return tv.tv_sec * 1000.0 + tv.tv_usec / 1000.0;
}

static int TestImageUpdateCmd(ClientData clientData, Tcl_Interp *interp, 
                             int objc, Tcl_Obj *const objv[]) {
    double start, end;
    int iterations = 100;
    int i, x, y;
    double total_time = 0.0;
    unsigned char *data;
    
    if (objc > 2) {
        Tcl_WrongNumArgs(interp, 1, objv, "?iterations?");
        return TCL_ERROR;
    }
    
    if (Tcl_GetIntFromObj(interp, objv[1], &iterations) != TCL_OK) {
        return TCL_ERROR;
    }

    Tk_Window tkwin = Tk_MainWindow(interp);
    if (tkwin == NULL) {
        Tcl_SetResult(interp, "No main window", TCL_STATIC);
        return TCL_ERROR;
    }

    Tk_Window targetWindow = Tk_NameToWindow(interp, ".f", tkwin);

    if (targetWindow == NULL) {
        Tcl_SetResult(interp, "No '.f' frame", TCL_STATIC);
        return TCL_ERROR;
    }

    Tk_MakeWindowExist(targetWindow);

    Window window    = Tk_WindowId(targetWindow);
    Display *display = Tk_Display(targetWindow);

    if (window == None) {
        Tcl_SetResult(interp, "Window not yet created", TCL_STATIC);
        return TCL_ERROR;
    }

    XGCValues gcValues;
    gcValues.graphics_exposures = False;
    GC gc = Tk_GetGC(targetWindow, GCGraphicsExposures, &gcValues);

    data = (unsigned char *)malloc(width * height * 4);
    if (data == NULL) {
        Tcl_SetResult(interp, "Memory allocation failed", TCL_STATIC);
        return TCL_ERROR;
    }
    
    for (y = 0; y < height; y++) {
        for (x = 0; x < width; x++) {
            int offset = (y * width + x) * 4;
            data[offset+0] = (x & 0xFF);
            data[offset+1] = (y & 0xFF);
            data[offset+2] = ((x + y) & 0xFF);
            data[offset+3] = 255;
        }
    }

    XImage *ximage = XCreateImage(
      display, 
      Tk_Visual(targetWindow),
      Tk_Depth(targetWindow),
      ZPixmap,    
      0,          
      (char*)data,
      width,
      height,
      32,
      width * 4
    );
    

    for (i = 0; i < iterations; i++) {
      int status = 0;
        start = get_time_ms();
	status = XPutImage(display, window, gc, ximage, 0, 0, 0, 0,
			   width, height); 
	end = get_time_ms();
        if (status) {
	  fprintf(stderr, "status: %d\n", status);
	}
        //XFlush(display);
        
        double elapsed = end - start;
        total_time += elapsed;

        if (i < 10 || i % 10 == 0) {
            printf("Iteration %d: %.3f ms\n", i, elapsed);
        }
    }
    
    double avg_time = total_time / iterations;
    printf("\nAverage time: %.3f ms\n", avg_time);
    
    char result[256];
    sprintf(result, "%.3f", avg_time);
    Tcl_SetResult(interp, result, TCL_VOLATILE);
    
    return TCL_OK;
}

#ifdef __cplusplus
extern "C" {
#endif

DLLEXPORT int Imagetest_Init(Tcl_Interp *interp) {
    if (Tcl_InitStubs(interp, "8.6-", 0) == NULL) {
        return TCL_ERROR;
    }
    
    if (Tk_InitStubs(interp, "8.6-", 0) == NULL) {
        return TCL_ERROR;
    }

    Tcl_CreateObjCommand(interp, "test_image_update", TestImageUpdateCmd, NULL, NULL);
    
    if (Tcl_PkgProvide(interp, "imagetest", "1.0") != TCL_OK) {
        return TCL_ERROR;
    }
    
    return TCL_OK;
}

#ifdef __cplusplus
}
#endif