/*
 * secde -- experimental lightweight Wayland/X11 server
 * Copyright (C) 2019  Samuel Lidén Borell
 *
 * 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 3 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, see <https://www.gnu.org/licenses/>.
 */

#include <linux/fb.h>
#include <sys/ioctl.h>
#include <sys/mman.h>

#include <stdio.h>
#include <string.h>

#include "fbdev.h"
#include "fbops.h"


static unsigned char *mapfb(int fd)
{
    struct fb_fix_screeninfo fixinfo;
    if (ioctl(fd, FBIOGET_FSCREENINFO, &fixinfo) == -1) {
        perror("Failed to get framebuffer fscreeninfo (ioctl failed)");
        return NULL;
    }
    printf("fbmem Start: %lx, length: %x\n", fixinfo.smem_start, fixinfo.smem_len);
    printf("MMIO Start: %lx, length: %x\n", fixinfo.mmio_start, fixinfo.mmio_len);
    return mmap(NULL, fixinfo.smem_len, PROT_WRITE|PROT_READ, MAP_SHARED, fd, 0/*fixinfo.smem_start*/);
    /* return mmap(NULL, fixinfo.smem_len, PROT_WRITE|PROT_READ, MAP_SHARED, fd, 0) + fixinfo.smem_start; */
    /*return mmap(NULL, fixinfo.mmio_len, PROT_WRITE|PROT_READ, MAP_SHARED, fd, fixinfo.mmio_start);*/
    /*return mmap(NULL, 1920*1080*3, PROT_WRITE|PROT_READ, MAP_SHARED, fd, 0);*/
}


int display_fbdev_init(struct FdInfo *info)
{
    (void) info;
    /* TODO */
    return 1;
}


void display_fbdev_test(struct FdInfo *info)
{
    int fd;
    unsigned char *screenptr;
    int x, y, w, h, i, bypp;
    struct fb_fix_screeninfo fixinfo;
    struct fb_var_screeninfo varinfo;

    struct FbPixelFormat format;
    struct FbSurf screen;
    struct FbDestSurf screendest = { &screen, &format };
    struct FbSurf offscreen;
    struct FbDestSurf offscreendest = { &offscreen, &format };

    fd = protohnd_getfd(info);
    screenptr = mapfb(fd);
    if (!screenptr) {
        perror("Failed to map framebuffer");
        return;
    }

    if (ioctl(fd, FBIOGET_FSCREENINFO, &fixinfo) == -1) {
        perror("Failed to get framebuffer fscreeninfo (ioctl failed)");
        return;
    }
    if (ioctl(fd, FBIOGET_VSCREENINFO, &varinfo) == -1) {
        perror("Failed to get framebuffer vscreeninfo (ioctl failed)");
        return;
    }
    screen.w = varinfo.xres;
    screen.h = varinfo.yres;
    screen.line_length = fixinfo.line_length;
    screen.pixels = screenptr;
    format.bytes_per_pixel = varinfo.bits_per_pixel/8;
    offscreen.w = varinfo.xres;
    offscreen.h = 1;
    offscreen.line_length = offscreen.w*format.bytes_per_pixel;
    printf("offscreen width: %d, bypp: %d, len %d\n", offscreen.w, format.bytes_per_pixel, offscreen.line_length);
    offscreen.pixels = malloc(offscreen.line_length);

#if 0
    printf("Test time\n");
    /*x = 100;
    w = 800;
    h = 900;
    for (y = 30; y < 30+h; y++) {
        memset(&screen[(x+varinfo.xoffset)*(varinfo.bits_per_pixel/8) + ((y+varinfo.yoffset)*fixinfo.line_length)], 0xFF, w*(varinfo.bits_per_pixel/8));
    }*/

    bypp = (varinfo.bits_per_pixel/8);
    /*
     * RPI3 perf:   255*20 frames = 5100 frames
     *
     * single memset:             28.213s = 180.8 fps
     * multiple memsets w/ mult:  28.134s (faster, so probably no diff)
     * multiple memcpys w/ mult:  28.063s (faster, so probably no diff)
     * scrolling w/ 17 px margin: 108.305s = 47 fps
     * scrolling w/ 32 px margin: 100.932s = 50.5 fps (so not an alignment problem)
     * copying row 0:             113.445s = 45.0 fps (so not a cache problem?)
     * "scrolling" w/o read:      29.560s = 172.5 fps ( = reading from the framebuffer is slow!)
     */
    for (i = 0; i <= 255*20; i++){
        /*x = 0;
        w = 1920;
        for (y = 0; y < 1080; y++) {
            memset(&screen[(x+varinfo.xoffset)*bypp + ((y+varinfo.yoffset)*fixinfo.line_length)], i, w*(varinfo.bits_per_pixel/8));
        }*/
        /*memset(screen, i, fixinfo.line_length*1080);*/
        /*x = 0;
        w = 1920;
        for (y = 0; y < 1080; y++) {
            memcpy(&screen[(x+varinfo.xoffset)*bypp + ((y+varinfo.yoffset)*fixinfo.line_length)], (char*)info-1024 + i, w*(varinfo.bits_per_pixel/8));
        }*/
        int m = 0;
        struct FbRect rect1, rect2, rect3;
        rect1.x = 0;
        rect1.y = 0;
        rect1.w = screen.w - 2*m;
        rect1.h = 1;
        rect2.x = m;
        rect2.y = m;
        rect2.w = rect1.w;
        rect2.h = 1;
        fbops_copysurf1(&offscreendest, 0, 0, &screen, &rect2);
        rect3.x = m;
        rect3.y = m+1;
        rect3.w = screen.w - 2*m;
        rect3.h = screen.h - 2*m - 1;
        fbops_moverect(&screendest, m, m, &rect3);
        fbops_copysurf1(&screendest, m, screen.h - m - 1, &offscreen, &rect1);
    }
    exit(0);

    /*screen[0] = 0xFF;*/
    /*printf("pixel 0 = %d\n", screen[(varinfo.xoffset)*(varinfo.bits_per_pixel/8) + (y+varinfo.yoffset) * fixinfo.line_length]);*/
    /*screen[(varinfo.xoffset)*(varinfo.bits_per_pixel/8) + (y+varinfo.yoffset) * fixinfo.line_length] = 0xFF;*/
#endif
}