package org.expeditee.gui.management;

import java.io.File;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.function.Consumer;
import java.util.stream.Collectors;

import org.expeditee.agents.ExistingFramesetException;
import org.expeditee.agents.InvalidFramesetNameException;
import org.expeditee.core.Colour;
import org.expeditee.core.Point;
import org.expeditee.gui.Frame;
import org.expeditee.gui.FrameIO;
import org.expeditee.gui.MessageBay;
import org.expeditee.items.Item;
import org.expeditee.items.ItemUtils;
import org.expeditee.items.Text;
import org.expeditee.setting.Setting;
import org.expeditee.settings.Settings;
import org.expeditee.settings.UserSettings;
import org.expeditee.settings.templates.TemplateSettings;

public class ProfileManager {

	private static final String USER_NAME_PATTERN_INTERNAL = "USER.NAME";
	private static final String DEFAULT = UserSettings.DEFAULT_PROFILE_NAME;
	private static final String[] startPages = { "exploratorysearch", "webbrowser" };
	public static final String USER_NAME_PATTERN = "${" + USER_NAME_PATTERN_INTERNAL + "}";

	public static Frame createProfile(String profileFor, Map<String, Setting> specifiedSettings,
			Map<String, Consumer<Frame>> notifyWhenGenerated) {
		ensureDefaultProfile();
		Frame profile = null;
		Frame profileOne = null;
		profileFor = FrameIO.ConvertToValidFramesetName(profileFor);
		
		try {
			profile = FrameIO.CreateFrameset(profileFor, FrameIO.PROFILE_PATH, true);
			profileOne = profile;
			profile.setTitle(profileFor + "'s Profile");
			Frame defaultFrame = FrameIO.LoadFrame(DEFAULT + "1");
			MessageBay.suppressMessages(true);
			UserSettings.UserName.set(profileFor);
			UserSettings.ProfileName.set(profileFor);
			
			int lastNumber = FrameIO.getLastNumber(defaultFrame.getFramesetName());
			for (int i  = 1; i <= lastNumber; i++) {
				// Load in next default, if it doesn't exist continue loop.
				defaultFrame = FrameIO.LoadFrame(DEFAULT + i);
				if (defaultFrame == null) { continue; }
				
				// Create the next next (currently blank) profile frame.
				// If there is frame gaps in the default (say if there is no 4.exp but there is
				// a 5.exp) then retain those gaps.
				// This way copied relative links work.
				while (profile.getNumber() < defaultFrame.getNumber()) {
					profile = FrameIO.CreateFrame(profile.getFramesetName(), null, null);
				}
				// Ensure we are working from a blank slate.
				profile.reset();
				profile.removeAllItems(profile.getAllItems());
				
				// For each item on defaultFrame:
				// 1. Set all items to be relatively linked so once copied their links correctly
				// point to the frame on the created profile rather than the default profile.
				// 2. Copy item from defaultFrame to the current profile frame being
				// constructed.
				// 3. Replace instance of ${USER.NAME} with 'profileFor'
				// 4. Replace settings values of copied items with those specified in
				// specifiedSettings (if present)
				Collection<Item> defaultAllItems = defaultFrame.getAllItems();
				Collection<Item> allItems = new ArrayList<Item>();
				for (Item item: defaultAllItems) {
					Item copyItem = item.copy();
					allItems.add(copyItem);
				}
				profile.addAllItems(allItems);
				
				for (Item item: profile.getAllItems()) {
					if (item instanceof Text) {
						String content = item.getText();
						item.setText(ResourceUtil.substitute(content, ProfileManager.USER_NAME_PATTERN_INTERNAL, profileFor));
					}
				}
				
				String category = profile.getTitle();
				List<String> settingsKeys = null;
				if (specifiedSettings != null) {
					settingsKeys = specifiedSettings.keySet().stream().filter(key -> 
						key.startsWith(category)).collect(Collectors.toList());
				}
				if (settingsKeys != null) {
					for (String key: settingsKeys) {
						Setting setting = specifiedSettings.get(key);
						String name = setting.getName();
						Text representation = setting.generateRepresentation(name, profile.getFramesetName());
						Collection<Text> canditates = profile.getTextItems();
						canditates.removeIf(text -> !text.getText().startsWith(representation.getText().split(" ")[0]));
						canditates.forEach(text -> {
							Point backupPos = text.getPosition();
							Item.DuplicateItem(representation, text);
							text.setText(representation.getText());
							text.setPosition(backupPos);
						});
					}
				}
				if (notifyWhenGenerated != null && notifyWhenGenerated.containsKey(category)) {
					notifyWhenGenerated.get(category).accept(profile);
				}
				
				FrameIO.SaveFrame(profile);
			}
			MessageBay.suppressMessages(false);
		} catch (InvalidFramesetNameException | ExistingFramesetException e) {
			String preamble = "Failed to create profile for '" + DEFAULT + "'. ";
			if (e instanceof InvalidFramesetNameException) {
				String message = preamble + "Profile names must start and end with a letter and must contain only letters and numbers";
				MessageBay.errorMessage(message);
			} else if (e instanceof ExistingFramesetException) {
				String message = preamble + "A frameset with this name already exists in: " + FrameIO.PROFILE_PATH;
				MessageBay.errorMessage(message);
			}
		}
		
		return profileOne;
	}

	/**
	 * Checks if the default profile exists, creates it if it does not.
	 */
	public static void ensureDefaultProfile() {
		// If we can load in the default profile, we have nothing to do.
		Frame defaultFrame = FrameIO.LoadProfile(DEFAULT);
		if (defaultFrame != null) {
			return;
		}
		
		// We do not have a default profile, generate one.
		createDefaultProfile();
	}

	/**
	 * Creates the default profile.
	 */
	private static void createDefaultProfile() {
		try {
			Frame profile = FrameIO.CreateFrameset(DEFAULT, FrameIO.PROFILE_PATH, true);
			
			// Give the first frame in the new profile an appropriate title.
			Text titleItem = profile.getTitleItem();
			if (titleItem != null) {
				titleItem.setText("Default Profile Frame");
			}
			
			// initial position for placing items.
			int xPos = 300;
			int yPos = 100;
			
			// Add documentation links
			Path helpDirectory = Paths.get(FrameIO.HELP_PATH);
			File[] helpFramesets = helpDirectory.toFile().listFiles();
			if (helpFramesets != null) {
				// Add the title for the help index
				Text helpPagesTitle = profile.addText(xPos, yPos, "@Expeditee Help", null);
				helpPagesTitle.setSize(25);
				helpPagesTitle.setFontStyle("Bold");
				helpPagesTitle.setFamily("SansSerif");
				helpPagesTitle.setColor(TemplateSettings.ColorWheel.get()[3]);
				
				xPos += 25;
				System.out.println("Installing frameset: ");
				
				boolean first_item = true;
				for (File helpFrameset : helpFramesets) {
					String framesetName = helpFrameset.getName();
					if (!FrameIO.isValidFramesetName(framesetName)) {
						continue;
					}

					if (first_item) {
						System.out.print("  " + framesetName);
						first_item = false;
					} else {
						System.out.print(", " + framesetName);
					}
					System.out.flush();

					Frame indexFrame = FrameIO.LoadFrame(framesetName + '1');
					// Look through the folder for help index pages
					if (indexFrame != null && ItemUtils.FindTag(indexFrame.getSortedItems(), "@HelpIndex") != null) {
						// yPos += spacing;
						yPos += 30;
						Text helpLink = profile.addText(xPos, yPos, '@' + indexFrame.getFramesetName(), null);
						helpLink.setLink(indexFrame.getName());
						helpLink.setColor(Colour.GREY);
					}
				}
				System.out.println();
			}
			
			// Reset position
			xPos = 50;
			yPos = 100;
			
			// Add start pages
			Path framesetDirectory = Paths.get(FrameIO.FRAME_PATH);
			File[] startPageFramesets = framesetDirectory.toFile().listFiles();
			if (startPageFramesets != null) {
				// Add Start Page title
				Text startPagesTitle = profile.addText(xPos, yPos, "@Start Pages", null);
				startPagesTitle.setSize(25);
				startPagesTitle.setFontStyle("Bold");
				startPagesTitle.setFamily("SansSerif");
				startPagesTitle.setColor(TemplateSettings.ColorWheel.get()[3]);

				xPos += 25;

				// Start Pages should be the first frame in its own frameset +
				// frameset name should be present in FrameUtils.startPages[].
				for (File startpagesFrameset : startPageFramesets) {
					String framesetName = startpagesFrameset.getName();

					// Only add link if frameset is a startpage
					for (int i = 0; i < startPages.length; i++) {
						if (framesetName.equals(startPages[i])) {
							Frame indexFrame = FrameIO.LoadFrame(framesetName + '1');

							// Add start page link
							if (indexFrame != null) {
								yPos += 30;
								Text startPageLink = profile.addText(xPos, yPos, '@' + indexFrame.getFramesetName(), null);
								startPageLink.setLink(indexFrame.getName());
								startPageLink.setColor(Colour.GREY);
							}
						}
					}
				}
			}

			// Add 'default' settings frameset
			Settings.Init();
			Text settingsLink = profile.addText(550, 100, "@Settings", null);
			settingsLink.setSize((float) 25.0);
			settingsLink.setFamily("SansSerif");
			settingsLink.setFontStyle("Bold");
			settingsLink.setColor(Colour.GREY);
			Settings.generateSettingsTree(settingsLink);
			System.out.println("@Settings: Default settings generation complete.");

			FrameIO.SaveFrame(profile);
			
			int lastNumber = FrameIO.getLastNumber(profile.getFramesetName());
			for (int i  = 1; i <= lastNumber; i++) {
				Frame frame = FrameIO.LoadFrame(DEFAULT + i);
				frame.setOwner(DEFAULT);
				for(Item item: frame.getAllItems()) {
					item.setOwner(DEFAULT);
					item.setRelativeLink();
				}
				frame.setChanged(true);
				FrameIO.SaveFrame(frame);
			}
			
		} catch (InvalidFramesetNameException | ExistingFramesetException e) {
			String preamble = "Failed to create profile for '" + DEFAULT + "'. ";
			if (e instanceof InvalidFramesetNameException) {
				String message = preamble + "Profile names must start and end with a letter and must contain only letters and numbers";
				MessageBay.errorMessage(message);
			} else if (e instanceof ExistingFramesetException) {
				String message = preamble + "A frameset with this name already exists in: " + FrameIO.PROFILE_PATH;
				MessageBay.errorMessage(message);
			}
			return;
		}
	}
}