#include "pico/stdlib.h"
#include "hardware/i2c.h"
#include "ssd1306.h"
#include "font.h" // A fonte precisa estar no mesmo diretório
#include <string.h>

#define I2C_PORT i2c0
#define SSD1306_I2C_ADDR 0x3C
#define SSD1306_WIDTH 128
#define SSD1306_HEIGHT 64
#define SSD1306_BUFFER_SIZE (SSD1306_WIDTH * SSD1306_HEIGHT / 8)

static uint8_t buffer[SSD1306_BUFFER_SIZE];

void ssd1306_send_cmd(uint8_t cmd) {
    uint8_t buf[] = {0x00, cmd};
    i2c_write_blocking(I2C_PORT, SSD1306_I2C_ADDR, buf, 2, false);
}

void ssd1306_send_data(uint8_t* data, size_t len) {
    uint8_t *temp_buf = malloc(len + 1);
    temp_buf[0] = 0x40;
    memcpy(temp_buf + 1, data, len);
    i2c_write_blocking(I2C_PORT, SSD1306_I2C_ADDR, temp_buf, len + 1, false);
    free(temp_buf);
}

void ssd1306_init() {
    ssd1306_send_cmd(0xAE); // display off
    ssd1306_send_cmd(0xD5); // set display clock div
    ssd1306_send_cmd(0x80); // suggested ratio
    ssd1306_send_cmd(0xA8); // set multiplex
    ssd1306_send_cmd(SSD1306_HEIGHT - 1);
    ssd1306_send_cmd(0xD3); // set display offset
    ssd1306_send_cmd(0x0); // no offset
    ssd1306_send_cmd(0x40 | 0x0); // line #0
    ssd1306_send_cmd(0x8D); // charge pump
    ssd1306_send_cmd(0x14); // enable
    ssd1306_send_cmd(0x20); // memory mode
    ssd1306_send_cmd(0x00); // 00 horizontal
    ssd1306_send_cmd(0xA1); // seg remap
    ssd1306_send_cmd(0xC8); // com out scan dir
    ssd1306_send_cmd(0xDA); // com pins
    ssd1306_send_cmd(0x12);
    ssd1306_send_cmd(0x81); // contrast
    ssd1306_send_cmd(0xCF);
    ssd1306_send_cmd(0xD9); // pre-charge
    ssd1306_send_cmd(0xF1);
    ssd1306_send_cmd(0xDB); // vcom detect
    ssd1306_send_cmd(0x40);
    ssd1306_send_cmd(0xA4); // resume
    ssd1306_send_cmd(0xA6); // normal display
    ssd1306_send_cmd(0x2E); // deactivate scroll
    ssd1306_send_cmd(0xAF); // display on
}

void ssd1306_clear() {
    memset(buffer, 0, SSD1306_BUFFER_SIZE);
}

void ssd1306_show() {
    ssd1306_send_data(buffer, SSD1306_BUFFER_SIZE);
}

void ssd1306_draw_pixel(int x, int y) {
    if (x < 0 || x >= SSD1306_WIDTH || y < 0 || y >= SSD1306_HEIGHT) return;
    buffer[x + (y / 8) * SSD1306_WIDTH] |= (1 << (y % 8));
}

void ssd1306_draw_char(int x, int y, int scale, char c) {
    if (c < 32 || c > 126) c = ' ';
    for (int i = 0; i < 8; i++) {
        for (int j = 0; j < 8; j++) {
            if ((font[c - 32][i] >> j) & 1) {
                for (int k = 0; k < scale; k++) {
                    for (int l = 0; l < scale; l++) {
                        ssd1306_draw_pixel(x + i * scale + k, y + j * scale + l);
                    }
                }
            }
        }
    }
}

void ssd1306_draw_string(int x, int y, int scale, char *s) {
    for (int i = 0; i < strlen(s); i++) {
        ssd1306_draw_char(x + i * 8 * scale, y, scale, s[i]);
    }
}