/**
 * @file lv_test_assert.c
 *
 * Copyright 2002-2010 Guillaume Cottenceau.
 *
 * This software may be freely redistributed under the terms
 * of the X11 license.
 *
 */

/*********************
 *      INCLUDES
 *********************/
#if LV_BUILD_TEST
#include "../lvgl.h"

#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdarg.h>
#include "unity.h"
#define PNG_DEBUG 3
#include <png.h>

/*********************
 *      DEFINES
 *********************/
//#define REF_IMGS_PATH "lvgl/tests/lv_test_ref_imgs/"
#define REF_IMGS_PATH "ref_imgs/"
#define ERR_FILE_NOT_FOUND  -1
#define ERR_PNG             -2

/**********************
 *      TYPEDEFS
 **********************/
typedef struct {
    int width, height;
    png_byte color_type;
    png_byte bit_depth;

    png_structp png_ptr;
    png_infop info_ptr;
    int number_of_passes;
    png_bytep * row_pointers;
} png_img_t;

/**********************
 *  STATIC PROTOTYPES
 **********************/
static int read_png_file(png_img_t * p, const char * file_name);
static int write_png_file(void * raw_img, uint32_t width, uint32_t height, char * file_name);
static void png_release(png_img_t * p);

/**********************
 *  STATIC VARIABLES
 **********************/

/**********************
 *      MACROS
 **********************/

/**********************
 *   GLOBAL FUNCTIONS
 **********************/

bool lv_test_assert_img_eq(const char * fn_ref)
{
    char fn_ref_full[512];
    sprintf(fn_ref_full, "%s%s", REF_IMGS_PATH, fn_ref);

    uint8_t * screen_buf;

    lv_obj_invalidate(lv_scr_act());
    lv_refr_now(NULL);

    extern lv_color32_t test_fb[];

    screen_buf = (uint8_t *)test_fb;

    png_img_t p;
    int res = read_png_file(&p, fn_ref_full);
    if(res == ERR_FILE_NOT_FOUND) {
        TEST_PRINTF("%s%s", fn_ref_full, " was not found, creating is now from the rendered screen");
        fflush(stderr);
        write_png_file(screen_buf, 800, 480, fn_ref_full);

        return true;
    }
    else if(res == ERR_PNG) {
        return false;
    }

    uint8_t * ptr_act = NULL;
    const png_byte * ptr_ref = NULL;

    bool err = false;
    int x, y, i_buf = 0;
    for(y = 0; y < p.height; y++) {
        png_byte * row = p.row_pointers[y];

        for(x = 0; x < p.width; x++) {
            ptr_ref = &(row[x * 3]);
            ptr_act = &(screen_buf[i_buf * 4]);

            uint32_t ref_px = 0;
            uint32_t act_px = 0;
            memcpy(&ref_px, ptr_ref, 3);
            memcpy(&act_px, ptr_act, 3);
            //printf("0xFF%06x, ", act_px);

            uint8_t act_swap[3] = {ptr_act[2], ptr_act[1], ptr_act[0]};

            if(memcmp(act_swap, ptr_ref, 3) != 0) {
                err = true;
                break;
            }
            i_buf++;
        }
        if(err) break;
    }

    if(err) {
        char fn_ref_no_ext[64];
        strcpy(fn_ref_no_ext, fn_ref);
        fn_ref_no_ext[strlen(fn_ref_no_ext) - 4] = '\0';

        char fn_err_full[512];
        sprintf(fn_err_full, "%s%s_err.png", REF_IMGS_PATH, fn_ref_no_ext);

        write_png_file(screen_buf, 800, 480, fn_err_full);
    }

    png_release(&p);

    return !err;

}

/**********************
 *   STATIC FUNCTIONS
 **********************/

static int read_png_file(png_img_t * p, const char * file_name)
{
    char header[8];    // 8 is the maximum size that can be checked

    /*open file and test for it being a png*/
    FILE * fp = fopen(file_name, "rb");
    if(!fp) {
        TEST_PRINTF("[read_png_file %s] could not be opened for reading", file_name);
        return ERR_FILE_NOT_FOUND;
    }

    size_t rcnt = fread(header, 1, 8, fp);
    if(rcnt != 8 || png_sig_cmp((png_const_bytep)header, 0, 8)) {
        TEST_PRINTF("[read_png_file %s]  not recognized as a PNG file", file_name);
        return ERR_PNG;
    }

    /*initialize stuff*/
    p->png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);

    if(!p->png_ptr) {
        TEST_PRINTF("[read_png_file %s] png_create_read_struct failed", file_name);
        return ERR_PNG;
    }

    p->info_ptr = png_create_info_struct(p->png_ptr);
    if(!p->info_ptr) {
        TEST_PRINTF("[read_png_file %s] png_create_info_struct failed", file_name);
        return ERR_PNG;
    }
    if(setjmp(png_jmpbuf(p->png_ptr))) {
        TEST_PRINTF("[read_png_file %s] Error during init_io", file_name);
        return ERR_PNG;
    }
    png_init_io(p->png_ptr, fp);
    png_set_sig_bytes(p->png_ptr, 8);

    png_read_info(p->png_ptr, p->info_ptr);

    p->width = png_get_image_width(p->png_ptr, p->info_ptr);
    p->height = png_get_image_height(p->png_ptr, p->info_ptr);
    p->color_type = png_get_color_type(p->png_ptr, p->info_ptr);
    p->bit_depth = png_get_bit_depth(p->png_ptr, p->info_ptr);

    p->number_of_passes = png_set_interlace_handling(p->png_ptr);
    png_read_update_info(p->png_ptr, p->info_ptr);

    /*read file*/
    if(setjmp(png_jmpbuf(p->png_ptr))) {
        TEST_PRINTF("[read_png_file %s] Error during read_image", file_name);
        return ERR_PNG;
    }
    p->row_pointers = (png_bytep *) malloc(sizeof(png_bytep) * p->height);

    int y;
    for(y = 0; y < p->height; y++)
        p->row_pointers[y] = (png_byte *) malloc(png_get_rowbytes(p->png_ptr, p->info_ptr));

    png_read_image(p->png_ptr, p->row_pointers);

    fclose(fp);
    return 0;
}


static int write_png_file(void * raw_img, uint32_t width, uint32_t height, char * file_name)
{
    png_structp png_ptr;
    png_infop info_ptr;

    /* create file */
    FILE * fp = fopen(file_name, "wb");
    if(!fp) {
        printf("###### %s\n", file_name);
        fflush(stdout);
        TEST_PRINTF("[write_png_file %s] could not be opened for writing", file_name);
        TEST_PRINTF("%s", file_name);
        return -1;
    }

    /* initialize stuff */
    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);

    if(!png_ptr) {
        TEST_PRINTF("[write_png_file %s] png_create_write_struct failed", file_name);
        return -1;
    }

    info_ptr = png_create_info_struct(png_ptr);
    if(!info_ptr) {
        TEST_PRINTF("[write_png_file %s] png_create_info_struct failed", file_name);
        return -1;
    }

    if(setjmp(png_jmpbuf(png_ptr))) {
        TEST_PRINTF("[write_png_file %s] Error during init_io", file_name);
        return -1;
    }

    png_init_io(png_ptr, fp);

    /* write header */
    if(setjmp(png_jmpbuf(png_ptr))) {
        TEST_PRINTF("[write_png_file %s] Error during writing header", file_name);
        return -1;
    }

    png_set_IHDR(png_ptr, info_ptr, width, height,
                 8, PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE,
                 PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);

    png_write_info(png_ptr, info_ptr);


    /* write bytes */
    if(setjmp(png_jmpbuf(png_ptr))) {
        TEST_PRINTF("[write_png_file %s] Error during writing bytes", file_name);
        return -1;
    }

    uint8_t * raw_img8 = (uint8_t *)raw_img;
    png_bytep * row_pointers = (png_bytep *) malloc(sizeof(png_bytep) * height);
    for(uint32_t y = 0; y < height; y++) {
        row_pointers[y] = malloc(3 * width);
        uint8_t * line = raw_img8 + y * width * 4;
        for(uint32_t x = 0; x < width; x++) {
            row_pointers[y][x * 3 + 0] = line[x * 4 + 2];
            row_pointers[y][x * 3 + 1] = line[x * 4 + 1];
            row_pointers[y][x * 3 + 2] = line[x * 4 + 0];
        }
    }
    png_write_image(png_ptr, row_pointers);


    /* end write */
    if(setjmp(png_jmpbuf(png_ptr))) {
        TEST_PRINTF("[write_png_file %s] Error during end of write", file_name);
        return -1;
    }
    png_write_end(png_ptr, NULL);

    /* cleanup heap allocation */
    for(uint32_t y = 0; y < height; y++) free(row_pointers[y]);
    free(row_pointers);

    png_destroy_write_struct(&png_ptr, &info_ptr);

    fclose(fp);
    return 0;
}


static void png_release(png_img_t * p)
{
    int y;
    for(y = 0; y < p->height; y++) free(p->row_pointers[y]);

    free(p->row_pointers);

    png_destroy_read_struct(&p->png_ptr, &p->info_ptr, NULL);
}


#endif