#include <stdio.h>
#include <pico/binary_info/code.h>
#include <pico/stdlib.h>
#include <hardware/i2c.h>
#include <hardware/adc.h>
#include <hardware/irq.h>
#include "pinout.h"
#include "lcd.h"

/*

 PINOUT

 Keypad - UART RX - receives symbols from STM8

 LCD - HD44780
    14 - RS (H-data, L-command)
    15 - EN (CLK)
    21,20,19,18 - D7,D6,D5,D4
    RW tied low (always write)
    TODO backlight switching

 I2C
    16 - SDA0
    17 - SCL0

    EEPROM 24C32 - addr 1010_000

    RTC DS3231 - addr 1101_000

 Relay
    5, 4, 22, 26 - active high

 Moisture
    28 - ADC2 0-3V




*/

void setup_output(uint num)
{
    gpio_set_dir(num, GPIO_OUT);
    gpio_put(num, 0);
    gpio_set_function(num, GPIO_FUNC_SIO);
}

// RX interrupt handler
void irq_uart() {
    while (uart_is_readable(uart0)) {
        uint8_t ch = uart_getc(uart0);

        // TODO do something useful
        if (uart_is_writable(uart0)) {
            uart_putc(uart0, ch);
        }
    }
}

void set_relays(bool one, bool two, bool three, bool four) {
    gpio_put(PIN_RE1, one);
    gpio_put(PIN_RE2, two);
    gpio_put(PIN_RE3, three);
    gpio_put(PIN_RE1, four);
}

void open_valve(uint num) {
    gpio_put(PIN_RE1, num == 1);
    gpio_put(PIN_RE2, num == 2);
    gpio_put(PIN_RE3, num == 3);
    gpio_put(PIN_RE4, num == 4);
}

uint16_t moisture_read() {
    adc_select_input(ADC_NUM_MOISTURE);
    return adc_read();
}

int main()
{
    // picotool binary info
    bi_decl(bi_1pin_with_name(PIN_LED, "LED"));
    bi_decl(bi_1pin_with_name(PIN_RE1, "RE1"));
    bi_decl(bi_1pin_with_name(PIN_RE2, "RE2"));
    bi_decl(bi_1pin_with_name(PIN_RE3, "RE3"));
    bi_decl(bi_1pin_with_name(PIN_RE4, "RE4"));
    bi_decl(bi_1pin_with_name(PIN_LCD_RS, "LCD RS"));
    bi_decl(bi_1pin_with_name(PIN_LCD_E, "LCD CLK"));
    bi_decl(bi_1pin_with_name(PIN_LCD_D7, "LCD D7"));
    bi_decl(bi_1pin_with_name(PIN_LCD_D6, "LCD D6"));
    bi_decl(bi_1pin_with_name(PIN_LCD_D5, "LCD D5"));
    bi_decl(bi_1pin_with_name(PIN_LCD_D4, "LCD D4"));
    bi_decl(bi_2pins_with_func(PIN_I2C_SDA, PIN_I2C_SCL, GPIO_FUNC_I2C));
    bi_decl(bi_1pin_with_name(PIN_MOISTURE, "ADC (moisture)"));
    bi_decl(bi_program_description("Zavlaha Kuchynka"));

    setup_default_uart();
    irq_set_exclusive_handler(UART0_IRQ, irq_uart);
    irq_set_enabled(UART0_IRQ, true);
    uart_set_irq_enables(uart0, 1, 0);

    /* On-board LED */
    setup_output(PIN_LED);

    /* Valve relays */
    setup_output(PIN_RE1);
    setup_output(PIN_RE2);
    setup_output(PIN_RE3);
    setup_output(PIN_RE4);

    /* LCD */
    setup_output(PIN_LCD_RS);
    setup_output(PIN_LCD_RW);
    setup_output(PIN_LCD_E);
    setup_output(PIN_LCD_D7);
    setup_output(PIN_LCD_D6);
    setup_output(PIN_LCD_D5);
    setup_output(PIN_LCD_D4);

    /* I2C */
    i2c_init(i2c0, 100 * 1000); // 100 kbps - play it safe
    gpio_set_function(PIN_I2C_SDA, GPIO_FUNC_I2C);
    gpio_set_function(PIN_I2C_SCL, GPIO_FUNC_I2C);
    gpio_pull_up(PIN_I2C_SDA);
    gpio_pull_up(PIN_I2C_SCL);

    /* ADC for moisture */
    adc_init();
    adc_gpio_init(PIN_MOISTURE);

    lcd_init();
    lcd_puts("HELLO WORLD!");

    uint cnt = 0;
    char buf[16];
    while (1) {
        lcd_clear();
        lcd_puts("HELLO WORLD!");

        gpio_put(PIN_LED, 1); // LED on

        uint16_t moisture = moisture_read();
        sprintf(buf, "ADC = %lu", moisture);
        lcd_xy(0, 1);
        lcd_puts(buf);
        lcd_xy(15, 3);
        lcd_putc('0' + cnt);

        sleep_ms(100);
        gpio_put(PIN_LED, 0); // LED off
        sleep_ms(100);

        // demo that valve control works
        cnt += 1;
        if (cnt == 5) {
            cnt = 0;
        }
        open_valve(cnt);
    }
}