/*
 * display2.cpp
 *
 *  Created on: Sep 26, 2017
 *  Updated:
 *      Author: Philipp Hinz/Sebastian Vendt
 */
#include <stdlib.h>
#include <pthread.h>
#include <time.h>
#include <unistd.h>
#include <string.h>

#include "display2.h"

#include "global.h"
#include "logger.h"
#include "database.h"
#include "timer.h"
#include "lcd.h"
#include "coffee.h"
#include "hal.h"
#include "events.h"
#include "DS18B20.h"

#define CURRENT	0
#define NEXT	1

//timeouts for the transitions in ms
#define TIMEOUT_PREBREW		1000
#define TIMEOUT_POSTBREW	9000

display_lang_t displayLang;
timer displayTimer(displayTimerHandler);
int lcd = 0;
// currently only the history of states is of interest
coffee_status_t coffeeState[] = {STATE_OFF, STATE_NULL}; // current - next state
coffee_mode_t coffeeMode[] = {MODE_STATE, MODE_NULL};
coffee_menuPage_t coffeePage[] = {PAGE_SOFTOFF, PAGE_NULL};
bool coffeeDescaling = false;
refreshRate_t currentRefreshRate = refresh_std;
uint16_t holdNext[3] = {0, 0, 0}; 	//holdtime of the new {state, Mode, Page} in ms
uint16_t nextWaitTime[3] = {0, 0, 0}; //actual waiting time of the new {state, Mode, Page}


typedef enum {
	state_idx = 0,
	mode_idx = 1,
	page_idx = 2
} idx_t;


void switchToNextPage(coffee_menuPage_t* history);
void switchToNextMode(coffee_mode_t* history);
void switchToNextState(coffee_status_t* history);
void setRefreshRate(refreshRate_t rate);
void setSwitchToNextTimeout(idx_t idx, uint16_t millis);

void displayPrintTemp(int line);
void displayPrintStats(int line);
void displayPrintStats2(int line);
void displayPrintNextDesc(int line);
void displayPrintPostBrew(int line);
void displayPrintBrewManual(int line);
void displayPrintFlow(int line);
void displayPrintCleanCycle(int line);
void displayStateUpdated(event_t *event);
void displayModeUpdated(event_t *event);
void displayPageUpdated(event_t *event);
void displayDescaling(event_t *event);
void displayPrintLogo(void);
void displayPrintNum(int line, uint16_t num, char* unitstr);
void displayClearLine(int line);
void displayTerminate(event_t *e);
void track(idx_t idx);

/**
 * Prints out the current time in a centered position
 * @param line Target line in display
 */
void displayPrintTime(int line) {
	time_t rawtime;
	struct tm * timeinfo;
	if (line > DISPLAY_ROWS)
		line = 0;

	time(&rawtime);
	timeinfo = localtime(&rawtime);
	lcdPosition(lcd, 0, line);
	lcdPrintf(lcd, "    %.2d:%.2d:%.2d    ", timeinfo->tm_hour,
			timeinfo->tm_min, timeinfo->tm_sec);
}

/**
 * Prints out the current temperature in a centered position
 * @param line Target line in display
 */
void displayPrintTemp(int line) {
	//TODO: the temperature is wrong(old value) the first time the page is opened
	//after the first refresh the right temperature is displayed
	//no idea where this comes from, datasheet says nothing about dummy readouts.
	//no old values are used, conversion is started before every readout...
	//Quick fix:
	DS18B20_readTemp();
	if (line > DISPLAY_ROWS)
		line = 0;

	lcdPosition(lcd, 0, line);
	lcdPrintf(lcd, "       %d C      ", DS18B20_readTemp());
}
/**
 * Prints the total epsressi brewed since reset
 */
void displayPrintStats(int line) {
	char buffer[17];
	if (line > DISPLAY_ROWS)
			line = 0;

	lcdPosition(lcd, 0, line);
	sprintf(buffer, "%7d espressi", getBrewCounter());
	lcdPrintf(lcd, buffer);
}
/**
 * Prints the total heating time in kWh
 */
void displayPrintStats2(int line) {
	char buffer[17];
	if (line > DISPLAY_ROWS)
		line = 0;

	uint64_t totalkWh = 2 * halGetTotalHeatingTime()/(60*60);
	sprintf(buffer, "%lld kWh", totalkWh);
	displayPrintLn(line, buffer, true);
}

/**
 * Prints the remaining time or the remaining cups until the next descaling is necessary
 */
void displayPrintNextDesc(int line) {
	char buffer[17];
	if (line > DISPLAY_ROWS) line = 0;

	sprintf(buffer, "%d d or %d C", checkDirtyTime(), checkDirtyEspresso());
	displayPrintLn(line, buffer, true);
}

/**
 *
 */
void displayPrintPostBrew(int line) {
	char buffer[17];
	if (line > DISPLAY_ROWS) line = 0;

	float brewTime = (float)halGetLastFlowTime();

	sprintf(buffer, "%.1f ml / %.1f s", halGetLastFlow(), brewTime / 1000);
	displayPrintLn(line, buffer, true);
}

void displayPrintBrewManual(int line) {
	char buffer[17];
	if (line > DISPLAY_ROWS) line = 0;

	float brewTime = (float)halGetFlowTime();

	sprintf(buffer, "%.1f ml / %.1f s", halGetFlow(), brewTime / 1000);
	displayPrintLn(line, buffer, true);
}

/**
 * Prints out the total volume flow
 * @param line Target line in display
 */
void displayPrintFlow(int line) {
	float flow = halGetFlow();
	lcdPosition(lcd, 0, line);
	lcdPrintf(lcd, "%s: %.0f ml    ", displayGetString(str_flow), flow);
}

/**
 * Prints the current cycle of the cleaning process
 */
void displayPrintCleanCycle(int line) {
	char buffer[17];
	if (line > DISPLAY_ROWS) line = 0;
	sprintf(buffer, "%2d of %2d", getCurrentCleanCycle(), CLEANING_CYCLES);
	displayPrintLn(line, buffer, true);
}

/**
 * Prints a string to a specific line, optionally centered.
 * This function also fills out the remaining row of the display with spaces,
 * to ensure there is no old data left.
 * @param line Target line in display
 * @param *str String to print
 * @param centered Print centered or not
 */
void displayPrintLn(int line, const char* str, bool centered) {
	char buf[DISPLAY_COLS + 1];
	int len = strlen(str);
	int i = 0;
	int spaces = 0;
	if (len > DISPLAY_COLS)
		len = DISPLAY_COLS;
	if (line > DISPLAY_ROWS)
		line = 0;
	if (centered) {
		spaces = (DISPLAY_COLS - len) / 2;
		if (spaces) {
			for (i = 0; i < spaces; i++) {
				buf[i] = ' ';
			}
		}
	}
	for (i = 0; i < len; i++) {
		buf[spaces + i] = str[i];
	}
	if ((len + spaces) < DISPLAY_COLS) { // fill remaining space
		for (i = i + spaces; i < DISPLAY_COLS; i++) {
			buf[i] = ' ';
		}
	}
	//draw the descaling star
	if(coffeeDescaling && line == 0){
		buf[15] = '*';
	}
	lcdPosition(lcd, 0, line);
	buf[DISPLAY_COLS] = '\0';
	lcdPrintf(lcd, buf);
}

/**
 * Updates the display state to the matching coffee state
 * @param event Event data
 */
void displayStateUpdated(event_t *event) {
	if (event->len != sizeof(coffee_status_t)) {
		logger_error("display2.cpp: Invalid use of event %s\n", event->event);
		return;
	}
	coffee_status_t state = *(coffee_status_t*) event->data;
	coffeeState[NEXT] = state;
	displayTimer.call();
}

/**
 * Updates the display state to the matching coffee display mode
 * @param event Event data
 */

void displayModeUpdated(event_t *event) {
	if (event->len != sizeof(coffee_mode_t)) {
		logger_error("display2.cpp: Invalid use of event %s\n", event->event);
		return;
	}
	coffee_mode_t mode = *(coffee_mode_t*) event->data;
	coffeeMode[NEXT] = mode;
	displayTimer.call();
}

/**
 * Updates the display state to the matching coffee display page
 * The new state is put on hold (next) and the display can decided if it immediately makes the
 * new state to the current one or if a timeout is specified in which the new state is put on hold and the
 * state transition is processed.
 * One initial asynchronous call
 * @param event Event data
 */

void displayPageUpdated(event_t *event) {
	if (event->len != sizeof(coffee_menuPage_t)) {
		logger_error("display2.cpp: Invalid use of event %s\n", event->event);
		return;
	}
	coffee_menuPage_t page = *(coffee_menuPage_t*) event->data;
	coffeePage[NEXT] = page;
	displayTimer.call();
}

/**
 * Updates the current descaling status of the machine
 */
void displayDescaling(event_t *event) {
	if (event->len != sizeof(bool)) {
		logger_error("display2.cpp: Invalid use of event %s\n", event->event);
		return;
	}
	coffeeDescaling = *(bool*) event->data;
}

/**
 * Prints the logo (CoffeePi) and also the temperature with the logo (CoffeePi@72C) if the machine is on
 */
void displayPrintLogo(void) {
	char buffer[17];
	switch (coffeeState[CURRENT]) {
		case STATE_HEATING:
		case STATE_INITALHEATING:
		case STATE_IDLE:
			sprintf(buffer, "CoffeePi @ %dC", DS18B20_readTemp());
			break;
		default:
			sprintf(buffer, "CoffeePi");
			break;
	}
	displayPrintLn(0, buffer, true);
}

/**
 * Prints a integer number on the display
 * @param line: The line number where the number shall be printed
 * @param num: The number to be printed
 * @param unitstr: The unit string, e.g. ms
 */
void displayPrintNum(int line, uint16_t num, const char* unitstr) {
	displayClearLine(line);
	lcdPosition(lcd, 0, line);
	lcdPrintf(lcd, " %d %s", num, unitstr);
}

/**
 * Write spaces to the display line to clear previous content
 * @param num: The line number
 */
void displayClearLine(int line) {
	lcdPosition(lcd, 0, line);
	lcdPrintf(lcd, "                ");
}

/**
 * Handles cleanup before program termination
 */
void displayTerminate(event_t *e) {
	logger(V_BASIC, "display.cpp: Terminating\n");
	displayPrintLn(0, "CoffeePi", true);
	displayPrintLn(1, displayGetString(str_bye), true);
	displayTimer.stop();
}

/**
 * Main thread to handle display data
 * @param *threadid Thread ID
 */
void* displayThread(void* threadid) {
	//sleep(1); // Wait for other components to initialize
	displayTimer.start();
	logger(V_BASIC, "display.cpp: Initialized display Thread. Timer state: %d \n", displayTimer.isActive());
	while (1) {
		pause();
		if (1) {
			displayTimer.call();
		}
	}
	pthread_exit(EXIT_SUCCESS);
}

/**
 * Timer handler for display update
 * @param *threadid Thread ID
 */
void* displayTimerHandler(void* threadid) {
	//track time of the new state in hold and switch if necessary
	track(state_idx);
	track(page_idx);
	track(mode_idx);

	displayRefresh();
	pthread_exit(EXIT_SUCCESS);
}

/**
 * Tracks the elapsed time in ms of the new state waiting to become the current one if a hold time is specified
 */

void track(idx_t idx){
	if (holdNext[idx] != 0) {
		nextWaitTime[idx] += 1000 / currentRefreshRate;
		if (holdNext[idx] <= nextWaitTime[idx]) {
			switch(idx){
			case state_idx:
				switchToNextState(coffeeState);
				break;
			case page_idx:
				switchToNextPage(coffeePage);
				break;
			case mode_idx:
				switchToNextMode(coffeeMode);
				break;
			}
		}
	}
}

/**
 * Initializes display
 */
void displayInit(void) {
	lcd = lcdInit();
	if (lcd < 0)
		logger_error("display2.cpp: Error: unable to init LCD (%d)\n", lcd);
	lcdClear(lcd);
	lcdHome(lcd);
	displayPrintLn(0, (char*) "CoffeePi", true);
	displayPrintLn(1, (char*) "booting...", true);
	//lcdPrintf(lcd, "    CoffeePi       booting...");


	//setRefreshRate(refresh_std);
	currentRefreshRate = refresh_std;
	displayTimer.setDivider(20 / refresh_std);

	/**The following block comes from void* displayThread(void* threadid)
	 * The idea is that the initialization functions get the component ready to react on external events
	 * once the threads start, events might be triggered and every component can process them
	 * This should fix the TO_DO where a descaling event was triggered during startup of the coffeethread and
	 * the displaythread did not react to it since it hadn't subscribed to the event yet
	 */
	int tmp = sqlGetConf(CFGdisplaylang);
	if (!tmp || tmp >= lang_last)
		tmp = DEFAULT_LANG;
	displaySetLang((display_lang_t) tmp);
	event_subscribe("statechange", &displayStateUpdated, "display.cpp");
	event_subscribe("modechange", &displayModeUpdated, "display.cpp");
	event_subscribe("pagechange", &displayPageUpdated, "display.cpp");
	event_subscribe("terminate", &displayTerminate, "display.cpp");
	event_subscribe("descaling", &displayDescaling, "display.cpp");

	logger(V_BASIC, "display2.cpp Initialized display with a refresh rate of %d Hz\n",
				refresh_std);
}

/**
 * Sets the language of the display text
 * @param lang New language
 */

void displaySetLang(display_lang_t lang) {
	displayLang = lang;
}

/*
 *
 */
void switchToNextPage(coffee_menuPage_t* history){
	if(history[NEXT] != PAGE_NULL) {
		history[CURRENT] = history[NEXT];
		history[NEXT] = PAGE_NULL;

		holdNext[page_idx] = 0;
		nextWaitTime[page_idx] = 0;
	}
}

/*
 *
 */
void switchToNextMode(coffee_mode_t* history){
	if(history[NEXT] != MODE_NULL) {
		history[CURRENT] = history[NEXT];
		history[NEXT] = MODE_NULL;

		holdNext[mode_idx] = 0;
		nextWaitTime[mode_idx] = 0;
	}
}

/*
 *
 */
void switchToNextState(coffee_status_t* history){
	if(history[NEXT] != STATE_NULL) {
		history[CURRENT] = history[NEXT];
		history[NEXT] = STATE_NULL;

		holdNext[state_idx] = 0;
		nextWaitTime[state_idx] = 0;
	}
}

/**
 * sets the refresh rate of the the display
 * to one of the predefined refresh rates.
 */
void setRefreshRate(refreshRate_t rate) {
	if (currentRefreshRate != rate) {
		currentRefreshRate = rate;
		displayTimer.setDivider(20 / rate);
	}
}

/**
 * specifies a timeout at which the new state/mode/page will be made to the current one
 * This function is enables for special state/mode/page transitions which hold the new state while
 * the current transition is displayed. These cases set a timeout specifying how long the state transition should be paused.
 * After the time specified in the timeout the timerhandler of the display will switch the states and makes the new one to the current one.
 */
void setSwitchToNextTimeout(idx_t idx, uint16_t millis) {
	holdNext[idx] = millis;
}

/**
 * The core description of what will be displayed in what displaystate
 */

void displayRefresh(void) {
	//handle mode trainsitions
	switchToNextMode(coffeeMode);
	//FSM of the display
	if (coffeeMode[CURRENT] == MODE_STATE) {
		//handle state transitions
		if (coffeeState[NEXT] == STATE_BREW) { //Pre brew
			//check how long the new state is already in hold ... and either switch or process transition
			setSwitchToNextTimeout(state_idx, TIMEOUT_PREBREW);
			setRefreshRate(refresh_fast);
			displayPrintLogo();
			displayPrintLn(1, displayGetString(str_brewing), true);
			return;
		} else if ((coffeeState[CURRENT] == STATE_BREW || coffeeState[CURRENT] == STATE_BREWMANUAL) && coffeeState[NEXT] != STATE_NULL) { //Post brew
			setSwitchToNextTimeout(state_idx, TIMEOUT_POSTBREW);
			setRefreshRate(refresh_std);
			displayPrintLn(0, displayGetString(str_postBrew), true);
			displayPrintPostBrew(1);
			return;
		} else { //no special state transition -> make new state to the current one
			switchToNextState(coffeeState);
		}

		switch (coffeeState[CURRENT]) { //coffeeGetState()
		case STATE_IDLE:
			displayPrintLogo();
			displayPrintLn(1, displayGetString(str_ready), true);
			break;
		case STATE_INITALHEATING:
			displayPrintLogo();
			displayPrintLn(1, displayGetString(str_heating), true);
			break;
		case STATE_HEATING:
			displayPrintLogo();
			displayPrintLn(1, displayGetString(str_heatingready), true);
			break;
		case STATE_BREW:
			displayPrintLn(0, displayGetString(str_brewing), true);
			displayPrintFlow(1);
			break;
		case STATE_BREWMANUAL:
			setRefreshRate(refresh_fast);
			displayPrintLn(0, displayGetString(str_brewing), true);
			//displayPrintFlow(1);
			displayPrintBrewManual(1);
			break;
		case STATE_CLEANING:
			displayPrintLn(0, displayGetString(str_cleaning), true);
			displayPrintCleanCycle(1);
			break;
		case STATE_ERROR:
			displayPrintLogo();
			displayPrintLn(1, displayGetString(str_error), true);
			break;
		case STATE_WAIT_OFF:
			displayPrintLogo();
			displayPrintLn(1, displayGetString(str_waitoff), true);
			break;
		case STATE_OFF:
			displayPrintLogo();
			displayPrintTime(1);
			break;
		case STATE_FULLTANK:
			displayPrintLn(0, displayGetString(str_fullTank), true);
			displayClearLine(1);
			break;
		default:
			displayPrintLn(0, displayGetString(str_error), true);
			displayPrintLn(0, "???", true);
			break;
		}
	} else if (coffeeMode[CURRENT] == MODE_MENU) {
		//handle page transitions
		switchToNextPage(coffeePage);

		switch (coffeePage[CURRENT]) {
		case PAGE_SOFTOFF:
			displayPrintLn(0, displayGetString(str_menu), true);
			displayPrintLn(1, displayGetString(str_menu_softoff), true);
			break;
		case PAGE_KILL:
			displayPrintLn(0, displayGetString(str_menu), true);
			displayPrintLn(1, displayGetString(str_menu_kill), true);
			break;
		case PAGE_SINGLEESPRESSO:
			displayPrintLn(0, displayGetString(str_menu), true);
			displayPrintLn(1, displayGetString(str_menu_singleEspresso), true);
			break;
		case PAGE_STATS:
			displayPrintLn(0, displayGetString(str_menu_stats), true);
			displayPrintStats(1);
			break;
		case PAGE_STATS2:
			displayPrintLn(0, displayGetString(str_menu_stats2), true);
			displayPrintStats2(1);
			break;
		case PAGE_DESCALING:
			displayPrintLn(0, displayGetString(str_menu_nextdesc), true);
			displayPrintNextDesc(1);
			break;
		case PAGE_TEMP:
			displayPrintLn(0, displayGetString(str_menu_temp), true);
			displayPrintTemp(1);
			break;
		case PAGE_CLEAN:
			displayPrintLn(0, displayGetString(str_menu), true);
			displayPrintLn(1, displayGetString(str_menu_clean), true);
			break;
		case PAGE_REBOOT:
			displayPrintLn(0, displayGetString(str_menu), true);
			displayPrintLn(1, displayGetString(str_menu_reboot), true);
			break;
		case PAGE_EXIT:
			displayPrintLn(0, displayGetString(str_menu), true);
			displayPrintLn(1, displayGetString(str_menu_exit), true);
			break;
		case PAGE_SETTINGS:
			displayPrintLn(0, displayGetString(str_menu), true);
			displayPrintLn(1, displayGetString(str_menu_settings), true);
			break;
		case PAGE_RESETKWH:
			displayPrintLn(0, displayGetString(str_menu_settings), true);
			displayPrintLn(1, displayGetString(str_menu_resetkwh), true);
			break;
		case PAGE_RESETKWH_VAL: //confirmation dialog
			displayPrintLn(0, displayGetString(str_menu_resetkwh_val), true);
			displayClearLine(1);
			break;
		case PAGE_CHANGEPREINF:
			displayPrintLn(0, displayGetString(str_menu_settings), true);
			displayPrintLn(1, displayGetString(str_menu_changepreinf), true);
			break;
		case PAGE_CHANGEPREINF_VAL:
			displayPrintLn(0, displayGetString(str_menu_changepreinf), true);
			displayPrintNum(1, getCoffeeCfg()->amount_preinfusion, "ml");
			break;
		case PAGE_CHANGEBREWTIME:
			displayPrintLn(0, displayGetString(str_menu_settings), true);
			displayPrintLn(1, displayGetString(str_menu_changebrewtime), true);
			break;
		case PAGE_CHANGEBREWTIME_VAL:
			displayPrintLn(0, displayGetString(str_menu_changebrewtime), true);
			displayPrintNum(1, getCoffeeCfg()->time_infusion, "ms");
			break;
		case PAGE_CHANGEBREWML:
			displayPrintLn(0, displayGetString(str_menu_settings), true);
			displayPrintLn(1, displayGetString(str_menu_changebrewml), true);
			break;
		case PAGE_CHANGEBREWML_VAL:
			displayPrintLn(0, displayGetString(str_menu_changebrewml), true);
			displayPrintNum(1, getCoffeeCfg()->amount_espresso, "ml");
			break;
		case PAGE_CHANGESOAKTIME:
			displayPrintLn(0, displayGetString(str_menu_settings), true);
			displayPrintLn(1, displayGetString(str_menu_changesoaktime), true);
			break;
		case PAGE_CHANGESOAKTIME_VAL:
			displayPrintLn(0, displayGetString(str_menu_changesoaktime), true);
			displayPrintNum(1, getCoffeeCfg()->time_soak, "ms");
			break;
		case PAGE_CHANGEAUTORESET:
			displayPrintLn(0, displayGetString(str_menu_settings), true);
			displayPrintLn(1, displayGetString(str_menu_changeAutoReset), true);
			break;
		case PAGE_CHANGEAUTORESET_VAL:
			displayPrintLn(0, displayGetString(str_menu_changeAutoReset), true);
			displayPrintNum(1, halGetFlowResetTime(), "ms");
			break;
		case PAGE_LEAVESETTINGS:
			displayPrintLn(0, displayGetString(str_menu_settings), true);
			displayPrintLn(1, displayGetString(str_menu_leavesettings), true);
			break;
		default:
			displayPrintLn(0, displayGetString(str_menu), true);
			displayPrintLn(1, "???", true);
			break;
		}
	}
}

/**
 * Returns the matching translation of a string
 * @param string Requested string
 * @return Translated string
 */

const char* displayGetString(display_strings_t string) {
	if (displayLang >= lang_last)
		displayLang = DEFAULT_LANG;
	return display_strings[string].text[displayLang];
}