#include "lcd_hd44780.h"
#include <stddef.h>

static int isStructOk(cm_lcd_hd44780_t *inst){

	if(inst == NULL)return 0;
	if(inst->setGetGpio_event == NULL) return 0;
	if(inst->wait_event == NULL) return 0;

	return 1;

}

void lcd_hd44780_writeToDisp(cm_lcd_hd44780_t *inst){
	
	inst->setGetGpio_event(&(inst->gpio_data),LCD_HD44780_SET);
}
/*
void lcd_hd44780_clearDisp(lcd_hd44780_t *inst){

	return;
	
}

void lcd_hd44780_printf(lcd_hd44780_t *inst, char *string){
	
	return;
	
}*/

static int lcd_write_8bit(cm_lcd_hd44780_t *inst, uint8_t dataOrCmd, hd44780_InstData_t mode){

	// Set cmd on databus
	inst->gpio_data.data_bus = dataOrCmd;

	// We want to set display
	inst->gpio_data.rw_pin = LCD_HD44780_SET;

	// We want to write an instruction.
	inst->gpio_data.rs_pin = mode;

	// E pin must be high when data is not ready yet.
	inst->gpio_data.e_pin = 1;

	inst->setGetGpio_event(&(inst->gpio_data),LCD_HD44780_SET);

	// Then Clock data in with  E pin. Data is clocked on Falling edge:
	inst->gpio_data.e_pin = 0;
	inst->setGetGpio_event(&(inst->gpio_data),LCD_HD44780_SET);

	// Then set E pin high so its ready for next time:
	inst->gpio_data.e_pin = 1;
	inst->setGetGpio_event(&(inst->gpio_data),LCD_HD44780_SET);

	return 0;

}

static void lcd_writeCmd_disp(cm_lcd_hd44780_t *inst, hd44780_cmd_t cmd, hd44780_setGet_t getSet){


	if(inst->bit_mode == LCD_HD44780_BITMODE_8BIT){

		lcd_write_8bit(inst, cmd, LCD_HD44780_INSTRUCTION);

	}else{

		// Write MSB first.
		lcd_write_8bit(inst, (cmd >> 4) & 0xf, LCD_HD44780_INSTRUCTION);
		// Write LSB last.
		lcd_write_8bit(inst, cmd & 0xf, LCD_HD44780_INSTRUCTION);
	}

}

void lcd_hd44780_initDisp(cm_lcd_hd44780_t *inst){

	// Make sure E pin is high when data isnt ready on BUS!
	inst->gpio_data.e_pin = 1;
	inst->setGetGpio_event(&(inst->gpio_data),LCD_HD44780_SET);

	// Wait for more than 15ms after VCC rise..
	inst->wait_event(15);
	lcd_writeCmd_disp(inst, LCD_HD44780_FUNCTION_SET,LCD_HD44780_SET);

	// Wait for 4.1ms..
	// Delay(4)
	inst->wait_event(4);

	lcd_writeCmd_disp(inst, LCD_HD44780_DISP_ONOFF_CTL,LCD_HD44780_SET);

	// delay 100us
	inst->wait_event(1);

	lcd_writeCmd_disp(inst, LCD_HD44780_ENTRY_MODE,LCD_HD44780_SET);



}

void lcd_hd44780_regGpioEvt(cm_lcd_hd44780_t *inst, setGet_Gpio_Event_fpt getGpioEvt_fpt){
	
	if(inst == NULL)return;
	if(getGpioEvt_fpt == NULL) return;

	inst->setGetGpio_event = getGpioEvt_fpt;
}

void lcd_hd44780_regWaitEvt(cm_lcd_hd44780_t *inst, wait_ms_Event_fpt waitEvt_fpt){

	if(inst == NULL)return;
	if(waitEvt_fpt == NULL) return;

	inst->wait_event = waitEvt_fpt;
}


void lcd_hd44780_init(cm_lcd_hd44780_t *inst, lcd_hd44780_bitmode bit_mode){
	
	if(!isStructOk(inst)) return;

	inst->bit_mode = bit_mode;
	lcd_hd44780_initDisp(inst);

	return;
}