/* 
 * (c) danielinux 2019
 * GPLv.2
 *
 * See LICENSE for details
 */
#include <stdlib.h>
#include <string.h>
#include "display.h"
#include "systick.h"
#include "system.h"


static uint8_t contrast = 0xcf;


void display_scroll(void *priv, uint8_t line)
{
    display_send_cmd1(priv, SSD1306_SETSTARTLINE, (line % 0x40) + 0x40);
}

void display_setcontrast(void *priv, uint8_t c)
{
    contrast = c; 
    display_send_cmd1(priv, SSD1306_SETCONTRAST, contrast);
}

uint8_t display_getcontrast(void *priv)
{
    return contrast;
}

void display_clear(void *priv)
{

    int i,j;
    uint8_t zeros[8] = {0, 0, 0, 0, 0, 0, 0, 0 };
    display_send_cmd(NULL, 0x00);
    display_send_cmd(NULL, 0x10);

    for (i = 0; i < 8; i++)
    {
        display_send_cmd2(NULL, SSD1306_PAGEADDR, i, 0x00);
        display_send_cmd2(NULL, SSD1306_COLUMNADDR, 0, WIDTH - 1);
        for (j = 0; j < 16; j++)
            display_send_data(NULL, zeros, 8);
    }
    WFI();
}

void display_text(int row, const char *text)
{
    int k;
    uint8_t zeros[8] = {0, 0, 0, 0, 0, 0, 0, 0 };
    int len = strlen(text);
    if (len > 15)
        len = 15;

    display_send_cmd(NULL, 0x00);
    display_send_cmd(NULL, 0x10);
    WFI();
    display_send_cmd2(NULL, SSD1306_PAGEADDR, 7 - row, 0x00);
    display_send_cmd2(NULL, SSD1306_COLUMNADDR, 0, WIDTH - 1);
    for(k = 0; k < len; k++)
        display_send_data(NULL, fb_font[text[k]], 8);
    for(; k < 16; k++)
        display_send_data(NULL, zeros, 8);
}

void display_text_inverse(int row, const char *text)
{
    int k, j;
    uint8_t inv_buf[8];
    uint8_t ones[8] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF };
    int len = strlen(text);
    if (len > 15)
        len = 15;
    display_send_cmd(NULL, 0x00);
    display_send_cmd(NULL, 0x10);
    WFI();
    display_send_cmd2(NULL, SSD1306_PAGEADDR, 7 - row, 0x00);
    display_send_cmd2(NULL, SSD1306_COLUMNADDR, 0, WIDTH - 1);
    for(k = 0; k < len; k++) {
        for (j = 0; j < 8; j++)
            inv_buf[j] = ~fb_font[text[k]][j];
        display_send_data(NULL, inv_buf, 8);
    }
    for(; k < 16; k++)
        display_send_data(NULL, ones, 8);
}

int display_init(void *priv)
{
    int i;
    int k = 0;
    int row = 0;
    volatile int j;
    uint8_t dbuf2[64] = {};
    int page = 0;
    int seg = 0;
    volatile uint32_t now;


    for (i = 1; i < 65; i++) {
        dbuf2[i] = 0;
    }
    display_send_cmd(priv, SSD1306_DISPLAYOFF);
    display_send_cmd1(priv, 0xD6, 0x01);
    display_send_cmd(priv, 0xA1);
    display_setcontrast(priv, contrast);
    display_send_cmd1(priv, SSD1306_CHARGEPUMP,  0x14);
    display_send_cmd1(priv, SSD1306_MEMORYMODE,  0x00);
    display_send_cmd1(priv, SSD1306_SETCOMPINS, 0x12);
    display_send_cmd1(priv, SSD1306_SETDISPLAYOFFSET, 0x00);
    display_send_cmd1(priv, SSD1306_SETVCOMDETECT, 0x00);
    display_send_cmd1(priv, SSD1306_SETMULTIPLEX, 63);
    display_send_cmd(priv, SSD1306_COMSCANINC);
    display_send_cmd(priv, SSD1306_DISPLAYALLON_RESUME);
    display_send_cmd(priv, SSD1306_DISPLAYON);
    display_send_cmd(priv, 0x2E);
    
    display_send_cmd2(priv, SSD1306_PAGEADDR, 0, 0xFF);
    display_send_cmd2(priv, SSD1306_COLUMNADDR, 0, WIDTH - 1);
    display_send_cmd1(priv, SSD1306_SETSTARTLINE, 0);
    display_send_cmd(priv, 0x00);
    display_send_cmd(priv, 0x10);
    for (page = 0; page < 8; page++) {
        display_send_cmd2(priv, SSD1306_PAGEADDR, page, 0xFF);
        for (seg= 0; seg < 32; seg++) {
            display_send_data(priv, dbuf2, 8);
        }
        display_send_cmd1(priv, SSD1306_SETSTARTLINE, row);
    }
    return 0;
}