package gui;

import data.*;
import javafx.application.HostServices;
import javafx.beans.value.ChangeListener;
import javafx.beans.value.ObservableValue;
import javafx.collections.FXCollections;
import javafx.collections.ListChangeListener;
import javafx.collections.ObservableList;
import javafx.concurrent.Task;
import javafx.fxml.FXML;
import javafx.scene.control.*;
import javafx.scene.layout.Pane;
import org.apache.commons.lang3.StringUtils;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.controlsfx.control.CheckComboBox;

import java.io.File;
import java.io.UnsupportedEncodingException;
import java.util.*;
import java.util.regex.Pattern;

import static alg.XML_processing.readXML;
import static gui.GUIController.showAlert;
import static gui.Messages.*;

@SuppressWarnings("Duplicates")
public class CharacterAnalysisTab {
	public final static Logger logger = LogManager.getLogger(CharacterAnalysisTab.class);

	@FXML
	public Label selectedFiltersLabel;
	@FXML
	public Label solarFilters;

	@FXML
	private TextField msdTF;
	private ArrayList<Pattern> msd;
	private ArrayList<String> msdStrings;

	@FXML
	private CheckComboBox<String> taxonomyCCB;
	private ArrayList<String> taxonomy;

	@FXML
	private CheckBox calculatecvvCB;
	private boolean calculateCvv;

	@FXML
	private TextField stringLengthTF;
	private Integer stringLength;

	@FXML
	private ToggleGroup calculateForRB;
	private  CalculateFor calculateFor;

	@FXML
	private RadioButton lemmaRB;

	@FXML
	private RadioButton varietyRB;

	@FXML
	private Pane paneLetters;

	@FXML
	private Button computeNgramsB;

	@FXML
	private Button cancel;

	@FXML
	public ProgressBar ngramProgressBar;
	@FXML
	public Label progressLabel;

	@FXML
	private Hyperlink helpH;

	private enum MODE {
		LETTER
	}

	private MODE currentMode;

	private Corpus corpus;
	private HashMap<String, HashSet<String>> solarFiltersMap;
	private Filter filter;
	private boolean useDb;
	private HostServices hostService;

	private static final ObservableList<String> N_GRAM_COMPUTE_FOR_LETTERS = FXCollections.observableArrayList("različnica", "lema");
	private static final ObservableList<String> N_GRAM_COMPUTE_FOR_WORDS_ORTH = FXCollections.observableArrayList("različnica");


	// TODO: pass observables for taxonomy based on header scan
	// after header scan
	private ObservableList<String> taxonomyCCBValues;
	private CorpusType currentCorpusType;

	public void init() {
		currentMode = MODE.LETTER;
		toggleMode(currentMode);

		calculateForRB.selectedToggleProperty().addListener(new ChangeListener<Toggle>() {
			@Override
			public void changed(ObservableValue<? extends Toggle> observable, Toggle oldValue, Toggle newValue) {
				//logger.info("calculateForRB:", newValue.toString());
				RadioButton chk = (RadioButton)newValue.getToggleGroup().getSelectedToggle(); // Cast object to radio button
				calculateFor = CalculateFor.factory(chk.getText());
				logger.info("calculateForRB:", chk.getText());
				//System.out.println("Selected Radio Button - "+chk.getText());
			}
		});

		// msd
		msdTF.focusedProperty().addListener((observable, oldValue, newValue) -> {
			if (!newValue) {
				// focus lost
				String value = msdTF.getText();
				logger.info("msdTf: ", value);

				if (!ValidationUtil.isEmpty(value)) {
					ArrayList<String> msdTmp = new ArrayList<>(Arrays.asList(value.split(" ")));

					int nOfRequiredMsdTokens = 1;
					if (msdTmp.size() != nOfRequiredMsdTokens) {
						String msg = String.format(Messages.WARNING_MISMATCHED_NGRAM_AND_TOKENS_VALUES, nOfRequiredMsdTokens, msdTmp.size());
						logAlert(msg);
						showAlert(Alert.AlertType.ERROR, msg);
					}
					msd = new ArrayList<>();
					msdStrings = new ArrayList<>();
					for (String msdToken : msdTmp) {
						msd.add(Pattern.compile(msdToken));
						msdStrings.add(msdToken);
					}
					logger.info(String.format("msd accepted (%d)", msd.size()));

				} else if (!ValidationUtil.isEmpty(newValue)) {
					msd = new ArrayList<>();
					msdStrings = new ArrayList<>();
				}
			}
		});

		msdTF.setText("");
		msd = new ArrayList<>();

		// taxonomy
		if (Tax.getCorpusTypesWithTaxonomy().contains(corpus.getCorpusType())) {
			taxonomyCCB.getItems().removeAll();
			taxonomyCCB.getItems().setAll(corpus.getTaxonomy());
			taxonomyCCB.getCheckModel().getCheckedItems().addListener((ListChangeListener<String>) c -> {
				taxonomy = new ArrayList<>();
				ObservableList<String> checkedItems = taxonomyCCB.getCheckModel().getCheckedItems();
				taxonomy.addAll(checkedItems);
				logger.info(String.format("Selected taxonomy: %s", StringUtils.join(checkedItems, ",")));
			});
			taxonomyCCB.getCheckModel().clearChecks();
		} else {
			taxonomyCCB.setDisable(true);
		}

		// cvv
		calculatecvvCB.selectedProperty().addListener((observable, oldValue, newValue) -> {
			calculateCvv = newValue;
			logger.info("calculate cvv: " + calculateCvv);
		});


		// string length
		stringLengthTF.focusedProperty().addListener((observable, oldValue, newValue) -> {
			if (!newValue) {
				// focus lost
				String value = stringLengthTF.getText();
				if (!ValidationUtil.isEmpty(value)) {
					if (!ValidationUtil.isNumber(value)) {
						logAlert("stringlengthTf: " + WARNING_ONLY_NUMBERS_ALLOWED);
						GUIController.showAlert(Alert.AlertType.ERROR, WARNING_ONLY_NUMBERS_ALLOWED);
					}
					stringLength = Integer.parseInt(value);
				} else {
					GUIController.showAlert(Alert.AlertType.ERROR, WARNING_MISSING_STRING_LENGTH);
					stringLengthTF.setText("1");
					logAlert(WARNING_MISSING_STRING_LENGTH);
				}
			}
		});

		computeNgramsB.setOnAction(e -> {
			compute();
			logger.info("compute button");
		});

        helpH.setOnAction(e -> openHelpWebsite());

		cancel.setVisible(false);
	}

	/**
	 * case a: values for combo boxes can change after a corpus change
	 * <ul>
	 * <li>different corpus type - reset all fields so no old values remain</li>
	 * <li>same corpus type, different subset - keep</li>
	 * </ul>
	 * <p>
	 * case b: values for combo boxes can change after a header scan
	 * <ul>
	 * <li>at first, fields are populated by corpus type defaults</li>
	 * <li>after, with gathered data</li>
	 * </ul>
	 * <p></p>
	 * ngrams: 1
	 * calculateFor: word
	 * msd:
	 * taxonomy:
	 * skip: 0
	 * iscvv: false
	 * string length: 1
	 */
	public void populateFields() {
		// corpus changed if: current one is null (this is first run of the app)
		// or if currentCorpus != gui's corpus
		boolean corpusChanged = currentCorpusType == null
				|| currentCorpusType != corpus.getCorpusType();

		// TODO: check for GOS, GIGAFIDA, SOLAR...
		// refresh and:
		// TODO if current value != null && is in new calculateFor ? keep : otherwise reset
		if (calculateFor == null) {
			calculateForRB.selectToggle(lemmaRB);
			calculateFor = CalculateFor.factory(calculateForRB.getSelectedToggle().toString());
		}

		if (!filter.hasMsd()) {
			// if current corpus doesn't have msd data, disable this field
			msd = new ArrayList<>();
			msdTF.setText("");
			msdTF.setDisable(true);
			logger.info("no msd data");
		} else {
			if (ValidationUtil.isEmpty(msd)
					|| (!ValidationUtil.isEmpty(msd) && corpusChanged)) {
				// msd has not been set previously
				// or msd has been set but the corpus changed -> reset
				msd = new ArrayList<>();
				msdTF.setText("");
				msdTF.setDisable(false);
				logger.info("msd reset");
			} else if (!ValidationUtil.isEmpty(msd) && !corpusChanged) {
				// if msd has been set, but corpus type remained the same, we can keep any set msd value
				msdTF.setText(StringUtils.join(msdStrings, " "));
				msdTF.setDisable(false);
				logger.info("msd kept");
			}
		}

		// TODO: taxonomy: refresh and keep if in new taxonomy, otherwise empty (no selection)

		// keep calculateCvv
		calculatecvvCB.setSelected(calculateCvv);

		// keep string length if set
		if (stringLength != null) {
			stringLengthTF.setText(String.valueOf(stringLength));
		} else {
			stringLengthTF.setText("1");
			stringLength = 1;
		}

		// TODO: trigger on rescan
		if ((currentCorpusType != null && currentCorpusType != corpus.getCorpusType())) {
			// user changed corpus (by type) or by selection & triggered a rescan of headers
			// see if we read taxonomy from headers, otherwise use default values for given corpus
			ObservableList<String> tax = corpus.getTaxonomy();
			taxonomyCCBValues = tax != null ? tax : Taxonomy.getDefaultForComboBox(corpus.getCorpusType());

			currentCorpusType = corpus.getCorpusType();
			// setTaxonomyIsDirty(false);
		} else {

		}

		// see if we read taxonomy from headers, otherwise use default values for given corpus
		ObservableList<String> tax = corpus.getTaxonomy();
		taxonomyCCBValues = tax != null ? tax : Taxonomy.getDefaultForComboBox(corpus.getCorpusType());
		taxonomyCCB.getItems().addAll(taxonomyCCBValues);

	}

	/**
	 * Toggles visibility for panes which hold fields for skipgram value (not applicable when calculating for letters) etc.,
	 * sets combobox values to what is applicable ...
	 *
	 * @param mode
	 */
	public void toggleMode(MODE mode) {
		if (mode == null) {
			mode = currentMode;
		}

		logger.info("mode: ", mode.toString());

		if (mode == MODE.LETTER) {
			paneLetters.setVisible(true);

			// populate with default cvv length value
			if (stringLength == null) {
				stringLengthTF.setText("1");
				stringLength = 1;
			} else {
				stringLengthTF.setText(String.valueOf(stringLength));
			}

			// if calculateFor was selected for something other than a word or a lemma -> reset
			if (!(calculateFor == CalculateFor.WORD || calculateFor == CalculateFor.LEMMA)) {
				// if the user selected something else before selecting ngram for letters, reset that choice
				calculateFor = CalculateFor.LEMMA;
				calculateForRB.selectToggle(lemmaRB);
			}
		}

		// override if orth mode, allow only word
		if (corpus.isGosOrthMode()) {
			// TODO change to
			varietyRB.setDisable(true);
			msdTF.setDisable(true);
		} else {
			msdTF.setDisable(false);
			varietyRB.setDisable(false);
		}
	}

	private void compute() {
		Filter filter = new Filter();
		filter.setNgramValue(0);
		filter.setCalculateFor(calculateFor);
		filter.setMsd(msd);
		filter.setTaxonomy(Tax.getTaxonomyCodes(taxonomy, corpus.getCorpusType()));
		filter.setAl(AnalysisLevel.STRING_LEVEL);
		filter.setSkipValue(0);
		filter.setIsCvv(calculateCvv);
		filter.setSolarFilters(solarFiltersMap);
		filter.setStringLength(stringLength);

		String message = Validation.validateForStringLevel(filter);
		if (message == null) {
			// no errors
			logger.info("Executing: ", filter.toString());
			StatisticsNew statistic = new StatisticsNew(corpus, filter, useDb);
			execute(statistic);
		} else {
			logAlert(message);
			showAlert(Alert.AlertType.ERROR, "Prosim izpolnite polja:", message);
		}
	}

	private void openHelpWebsite(){
		hostService.showDocument(Messages.HELP_URL);
	}

	private void logAlert(String alert) {
		logger.info("alert: " + alert);
	}

	public Corpus getCorpus() {
		return corpus;
	}

	public void setCorpus(Corpus corpus) {
		this.corpus = corpus;

		if (corpus.getCorpusType() != CorpusType.SOLAR) {
			setSelectedFiltersLabel(null);
		} else {
			setSelectedFiltersLabel("/");
		}
	}

	public void setSelectedFiltersLabel(String content) {
		if (content != null) {
			solarFilters.setVisible(true);
			selectedFiltersLabel.setVisible(true);
			selectedFiltersLabel.setText(content);
		} else {
			solarFilters.setVisible(false);
			selectedFiltersLabel.setVisible(false);
		}
	}

	private void execute(StatisticsNew statistic) {
		logger.info("Started execution: ", statistic.getFilter());

		Collection<File> corpusFiles = statistic.getCorpus().getDetectedCorpusFiles();
		boolean corpusIsSplit = corpusFiles.size() > 1;

		final Task<Void> task = new Task<Void>() {
			@SuppressWarnings("Duplicates")
			@Override
			protected Void call() throws Exception {
				long i = 0;
				for (File f : corpusFiles) {
					readXML(f.toString(), statistic);
					i++;
					if (isCancelled()) {
						updateMessage(CANCELING_NOTIFICATION);
						break;
					}
					this.updateProgress(i, corpusFiles.size());
					this.updateMessage(String.format(ONGOING_NOTIFICATION_ANALYZING_FILE_X_OF_Y, i, corpusFiles.size(), f.getName()));
				}

				return null;
			}
		};

		ngramProgressBar.progressProperty().bind(task.progressProperty());
		progressLabel.textProperty().bind(task.messageProperty());

		task.setOnSucceeded(e -> {
			try {
				boolean successullySaved = statistic.saveResultToDisk();
				if (successullySaved) {
					showAlert(Alert.AlertType.INFORMATION, Messages.NOTIFICATION_ANALYSIS_COMPLETED);
				} else {
					showAlert(Alert.AlertType.INFORMATION, Messages.NOTIFICATION_ANALYSIS_COMPLETED_NO_RESULTS);
				}
			} catch (UnsupportedEncodingException e1) {
				showAlert(Alert.AlertType.ERROR, ERROR_WHILE_SAVING_RESULTS_TO_CSV);
				logger.error("Error while saving", e1);
			}

			ngramProgressBar.progressProperty().unbind();
			ngramProgressBar.setStyle(Settings.FX_ACCENT_OK);
			progressLabel.textProperty().unbind();
			progressLabel.setText("");
			cancel.setVisible(false);
		});

		task.setOnFailed(e -> {
			showAlert(Alert.AlertType.ERROR, ERROR_WHILE_EXECUTING);
			logger.error("Error while executing", e);
			ngramProgressBar.progressProperty().unbind();
			ngramProgressBar.setProgress(0.0);
			ngramProgressBar.setStyle(Settings.FX_ACCENT_NOK);
			progressLabel.textProperty().unbind();
			progressLabel.setText("");
			cancel.setVisible(false);
		});

		task.setOnCancelled(e -> {
			showAlert(Alert.AlertType.INFORMATION, Messages.NOTIFICATION_ANALYSIS_CANCLED);
			ngramProgressBar.progressProperty().unbind();
			ngramProgressBar.setProgress(0.0);
			ngramProgressBar.setStyle(Settings.FX_ACCENT_OK);
			progressLabel.textProperty().unbind();
			progressLabel.setText("");
			cancel.setVisible(false);
		});

		// When cancel button is pressed cancel analysis
		cancel.setOnAction(e -> {
			task.cancel();
			logger.info("cancel button");
		});

		cancel.setVisible(true);

		final Thread thread = new Thread(task, "task");
		thread.setDaemon(true);
		thread.start();
	}

	public void setSolarFiltersMap(HashMap<String, HashSet<String>> solarFiltersMap) {
		this.solarFiltersMap = solarFiltersMap;
	}

	public void setHostServices(HostServices hostServices){
		this.hostService = hostServices;
	}
}