package info.peper.vz.rest;

import java.text.DecimalFormat;
import java.text.DecimalFormatSymbols;
import java.text.NumberFormat;
import java.time.Duration;
import java.time.Instant;
import java.time.ZoneId;
import java.time.ZonedDateTime;
import java.time.temporal.ChronoField;
import java.util.List;
import java.util.Locale;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.web.bind.annotation.CrossOrigin;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import info.peper.vz.rest.bo.Statistics;
import info.peper.vz.rest.bo.db.Aggregate;
import info.peper.vz.rest.bo.db.EnergyPrice;

@RestController
class VzRestController {

	private static final Logger log = LoggerFactory.getLogger(VzRestController.class);

	@Autowired
	private JdbcTemplate jdbcTemplate;
	
	public VzRestController() {
	}
	
	@GetMapping("/rest-vz/latest-data")
	List<Aggregate> getLatestData(
			@RequestParam("houseId")final int houseId,
			@RequestParam("timeWindow")final int timeWindow) {
		return jdbcTemplate.query("SELECT * FROM tobias_aggregate2 WHERE house_id=? ORDER BY timestamp_start DESC LIMIT ?;",
				(rs, rowNum) -> new Aggregate(houseId, rs.getLong("timestamp_start"), rs.getLong("timestamp_end"), rs.getLong("produced_energy"), rs.getLong("obtained_energy"), rs.getLong("injected_energy")),
				houseId, timeWindow);
	}
	
	@GetMapping("/rest-vz/sums")
	Aggregate getData(@RequestParam("timestampStart")final long timestampStart,
			@RequestParam("timestampEnd")final long timestampEnd,
			@RequestParam("houseId")final int houseId,
			@RequestParam("solarFactor")final float solarFactor) {
		final List<Aggregate> aggregates;
		if (solarFactor == 1.0f) {
			aggregates = jdbcTemplate.query(
					"SELECT MIN(timestamp_start) AS min_ts_start, MAX(timestamp_end) AS max_ts_end, SUM(produced_energy)/3600 AS sum_produced, SUM(obtained_energy)/3600 AS sum_obtained, SUM(injected_energy)/3600 AS sum_injected FROM volkszaehler.tobias_aggregate2 WHERE house_id=? AND timestamp_start>=? AND timestamp_end<=?;", 
					(rs, rowNum) -> new Aggregate(houseId, rs.getLong("min_ts_start"), rs.getLong("max_ts_end"),
							rs.getLong("sum_produced"), rs.getLong("sum_obtained"), rs.getLong("sum_injected")),
					houseId ,timestampStart, timestampEnd);
		} else {
			aggregates = jdbcTemplate.query(
					"SELECT MIN(timestamp_start) AS min_ts_start, MAX(timestamp_end) AS max_ts_end, SUM(produced_energy * ?)/3600 AS sum_produced, SUM(GREATEST(obtained_energy + produced_energy - injected_energy - ? * produced_energy, 0))/3600 AS sum_obtained, SUM(ABS(LEAST(obtained_energy + produced_energy - injected_energy - ? * produced_energy, 0)))/3600 AS sum_injected FROM volkszaehler.tobias_aggregate2 WHERE house_id=? AND timestamp_start>=? AND timestamp_end<=?;", 
					(rs, rowNum) -> new Aggregate(houseId, rs.getLong("min_ts_start"), rs.getLong("max_ts_end"),
							rs.getLong("sum_produced"), rs.getLong("sum_obtained"), rs.getLong("sum_injected")),
					solarFactor, solarFactor, solarFactor, houseId ,timestampStart, timestampEnd);
		}
		if (aggregates.size() != 1) {
			throw new RuntimeException("Interal error in SQL query.");
		}
		final Aggregate aggregate = aggregates.iterator().next();
		
		log.debug("energyProduced: " + aggregate.getProducedEnergy() + " / energyObtained: " + aggregate.getObtainedEnergy() + " / injectedEnergy: " + aggregate.getInjectedEnergy());
		log.debug("timestampStart: " + timestampStart);
		log.debug("timestampEnd:   " + timestampEnd);
		log.debug("firstTimestamp: " + aggregate.getTimestampStart());
		log.debug("lastTimestamp:  " + aggregate.getTimestampEnd());
		
		return aggregate;
	}

	@GetMapping("/rest-vz/prices")
	List<EnergyPrice> getPrices(@RequestParam("timestampStart")final long timestampStart,
			@RequestParam("timestampEnd")final long timestampEnd,
			@RequestParam("houseId")final int houseId) {
		final List<EnergyPrice> prices = jdbcTemplate.query(
				"SELECT * FROM tobias_energy_price WHERE house_id=? AND timestamp_start < ? AND timestamp_end >= ? ORDER BY timestamp_start;", 
				(rs, rowNum) -> new EnergyPrice(rs.getInt("house_id"), rs.getLong("timestamp_start"), rs.getLong("timestamp_end"),
						rs.getFloat("price")),
				houseId ,timestampEnd, timestampStart);
		return prices;
	}
	
	@CrossOrigin(origins = "http://localhost:4200")
	@GetMapping(value="/rest-vz/stats", produces = {"application/json"})
	Statistics getStats(@RequestParam(name = "timestampStart", defaultValue = "-1")long timestampStart,
			@RequestParam(name = "timestampEnd", defaultValue = "-1")long timestampEnd,
			@RequestParam(name = "duration", defaultValue = "")final String duration,
			@RequestParam("houseId")final int houseId,
			@RequestParam(name = "solarFactor", defaultValue = "1.0")final float solarFactor) {
		
		if (!"".equals(duration)) {
			final Duration dur = Duration.parse(duration);
			timestampEnd = (Instant.now().toEpochMilli()/Calculator.INTERVAL)*Calculator.INTERVAL;
			timestampStart = ((dur.subtractFrom(Instant.now()).getLong(ChronoField.INSTANT_SECONDS)*1000)/Calculator.INTERVAL)*Calculator.INTERVAL;
		} else {
			if (timestampStart == -1) {
				timestampStart = jdbcTemplate.queryForObject("SELECT MIN(timestamp_start) AS ts FROM tobias_aggregate2 WHERE house_id=?;", Long.class, houseId);
			}
			if (timestampEnd == -1) {
				timestampEnd = jdbcTemplate.queryForObject("SELECT MAX(timestamp_end) AS ts FROM tobias_aggregate2 WHERE house_id=?;", Long.class, houseId);
			}
		}
		
		final List<EnergyPrice> prices = this.getPrices(timestampStart, timestampEnd, houseId);
		
		float savedMoney = 0;
		float payedMoney = 0;
		long totalProduced = 0;
		long totalObtained = 0;
		long totalInjected = 0;
		long timestampMin = Long.MAX_VALUE;
		long timestampMax = Long.MIN_VALUE;
		for (EnergyPrice price : prices) {
			final long tsStart = Math.max(price.getTimestampStart(), timestampStart);
			final long tsEnd = Math.min(price.getTimestampEnd(), timestampEnd);
			final Aggregate aggregate = getData(tsStart, tsEnd, houseId, solarFactor);
			payedMoney += (float)(aggregate.getObtainedEnergy()/1000000 * price.getPrice());
			savedMoney += (float)(aggregate.getProducedEnergy() - aggregate.getInjectedEnergy())/1000000 * price.getPrice();
			totalProduced += aggregate.getProducedEnergy();
			totalObtained += aggregate.getObtainedEnergy();
			totalInjected += aggregate.getInjectedEnergy();
			if (timestampMin > aggregate.getTimestampStart()) {
				timestampMin = aggregate.getTimestampStart();
			}
			if (timestampMax < aggregate.getTimestampEnd()) {
				timestampMax = aggregate.getTimestampEnd();
			}
		}
		return new Statistics(timestampMin, timestampMax, totalProduced, totalInjected, totalObtained,
				(long)(savedMoney*100), (long)(payedMoney*100));
	}

	@GetMapping(value="/rest-vz/summary", produces = {"text/plain"})
	String getSummary(@RequestParam(name = "timestampStart", defaultValue = "-1")long timestampStart,
			@RequestParam(name = "timestampEnd", defaultValue = "-1")long timestampEnd,
			@RequestParam(name = "duration", defaultValue = "")final String duration,
			@RequestParam("houseId")final int houseId,
			@RequestParam(name = "solarFactor", defaultValue = "1.0")final float solarFactor) {
		
		final Statistics stats = this.getStats(timestampStart, timestampEnd, duration, houseId, solarFactor);
		
		final NumberFormat formatCurrency = new DecimalFormat("#,##0.00", new DecimalFormatSymbols(Locale.GERMAN));
		final NumberFormat formatPercent = new DecimalFormat("#,##0.00", new DecimalFormatSymbols(Locale.GERMAN));
		final NumberFormat formatEnergy = new DecimalFormat("#,##0.00", new DecimalFormatSymbols(Locale.GERMAN));
		final StringBuilder sb = new StringBuilder();
		sb.append("Start: .................................. " + ZonedDateTime.ofInstant(Instant.ofEpochMilli(stats.getTimestampStart()), ZoneId.systemDefault()).toString() + "\n");
		sb.append("Ende: ................................... " + ZonedDateTime.ofInstant(Instant.ofEpochMilli(stats.getTimestampEnd()), ZoneId.systemDefault()).toString() + "\n");
		sb.append("Erzeugter Strom von der Photovoltaik: ... " + formatEnergy.format((float)stats.getProducedEnergy()/1000000) + " kWh\n");
		sb.append("Eingespeister Strom von der Photovoltaik: " + formatEnergy.format((float)stats.getInjectedEnergy()/1000000) + " kWh\n");
		sb.append("Genutzter Strom von der Photovoltaik: ... " + formatEnergy.format((float)(stats.getProducedEnergy()-stats.getInjectedEnergy())/1000000) + " kWh (=");
		sb.append(formatPercent.format((float)(stats.getProducedEnergy()-stats.getInjectedEnergy())/(float)stats.getProducedEnergy()*100) + " %)\n");
		sb.append("Bezogener Strom: ........................ " + formatEnergy.format((float)stats.getObtainedEnergy()/1000000) + " kWh\n");
		sb.append("Autakie: ................................ " + formatPercent.format((float)(stats.getProducedEnergy()-stats.getInjectedEnergy())/(float)(stats.getObtainedEnergy()+stats.getProducedEnergy()-stats.getInjectedEnergy())*100) + " %\n");
		sb.append("Eingespartes Geld: ...................... " + formatCurrency.format(((float)stats.getSavedMoney())/100) + "€\n");
		sb.append("Stromkosten: ............................ " + formatCurrency.format(((float)stats.getPayedMoney())/100) + "€\n");
		return sb.toString();
	}
	
}