package org.expeditee.auth.account;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileWriter;
import java.io.IOException;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.KeyStoreException;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import java.security.cert.CertificateException;
import java.sql.SQLException;
import java.util.Base64;
import java.util.Collection;
import java.util.HashMap;
import java.util.Map;
import java.util.Random;
import java.util.function.Consumer;

import javax.crypto.SecretKey;
import javax.crypto.spec.SecretKeySpec;

import org.apollo.io.AudioPathManager;
import org.expeditee.agents.ExistingFramesetException;
import org.expeditee.agents.InvalidFramesetNameException;
import org.expeditee.auth.Actions;
import org.expeditee.auth.AuthenticatorBrowser;
import org.expeditee.auth.tags.AuthenticationTag;
import org.expeditee.core.Colour;
import org.expeditee.gui.DisplayController;
import org.expeditee.gui.Frame;
import org.expeditee.gui.FrameIO;
import org.expeditee.gui.MessageBay;
import org.expeditee.gui.MessageBay.Progress;
import org.expeditee.io.ExpReader;
import org.expeditee.items.Item;
import org.expeditee.items.PermissionPair;
import org.expeditee.items.Text;
import org.expeditee.items.UserAppliedPermission;
import org.expeditee.setting.GenericSetting;
import org.expeditee.setting.Setting;
import org.expeditee.setting.TextSetting;
import org.expeditee.settings.UserSettings;
import org.expeditee.settings.folders.FolderSettings;
import org.expeditee.settings.identity.secrets.KeyList;
import org.ngikm.cryptography.CryptographyConstants;

public class Create implements CryptographyConstants {
	
	/**
	 * Create a user account using the specified information in userdata.  Creates and stores user keys.
	 * @param userdata Should contain username, password and email.
	 */
	public static void createAccount(Map<AuthenticationTag, String> userdata) throws InvalidFramesetNameException, ExistingFramesetException, 
		KeyStoreException, NoSuchAlgorithmException, CertificateException, FileNotFoundException, ClassNotFoundException, IOException, SQLException {			
		// Track progress
		String message = "Creating new user account...";
		int progress = 0;
		int step = 16;

		// Extract user details
		String username = userdata.get(AuthenticationTag.Username);
		String password = userdata.get(AuthenticationTag.Password);
		String email = userdata.get(AuthenticationTag.Email);
		
		Progress progressBar = MessageBay.displayProgress(message);
		try {
			progressBar.UpdateMessage(message + "Generating Keys.", progress += step);
		} catch (Exception e) {
			e.printStackTrace();
		}
		DisplayController.refreshBayArea();

		// Generate keys
		//	Personal key
		Random rand = new SecureRandom();
		byte[] keyBytes = new byte[16];
		rand.nextBytes(keyBytes);
		SecretKey key = new SecretKeySpec(keyBytes, SymmetricAlgorithm);
		AuthenticatorBrowser.getInstance().putKey(username, password, key);
		String personalKey = Base64.getEncoder().encodeToString(key.getEncoded());
		//	Public and private keys
		KeyPairGenerator keyGen = KeyPairGenerator.getInstance(AsymmetricAlgorithm);
		keyGen.initialize(1024);
		KeyPair keyPair = keyGen.generateKeyPair();
		String publicKey = Base64.getEncoder().encodeToString(keyPair.getPublic().getEncoded());
		String privateKey = Base64.getEncoder().encodeToString(keyPair.getPrivate().getEncoded());
		
		try {
			progressBar.UpdateMessage(message + "Creating Profile Frameset.", progress += step);
		} catch (Exception e) {
			e.printStackTrace();
		}
		DisplayController.refreshBayArea();
		
		// Update in memory settings
		System.setProperty("user.name", username);
		UserSettings.UserName.set(username);
		UserSettings.ProfileName.set(username);
		UserSettings.setupDefaultFolders();
				
		// Establish the initial settings for the created user.
		Map<String, Setting> initialSettings = new HashMap<String, Setting>();
		initialSettings.put("settings.identity.secrets.PersonalKey", constructTextSetting("The AES key used to secure your profile frame - do not share with anyone!", "PersonalKey", personalKey));
		initialSettings.put("settings.identity.secrets.PrivateKey", constructTextSetting("The RSA key used to decrypt things encrypted with your RSA public key - do not share with anyone!", "PrivateKey", privateKey));
		initialSettings.put("settings.identity.PublicKey", constructTextSetting("The RSA key used to decrypt things encrypted with your RSA public key.", "PublicKey", publicKey));
		initialSettings.put("settings.identity.Email", constructGenericSetting(String.class, "Your public-facing email address.", "Email", email, username));
		initialSettings.put("settings.UserSettings.UserName", constructGenericSetting(String.class, "Username", "Username", username, username));
		initialSettings.put("settings.UserSettings.ProfileName", constructGenericSetting(String.class, "Profilename", "Profilename", username, username));
		initialSettings.put("settings.UserSettings.HomeFrame", constructGenericSetting(String.class, "The home frame", "HomeFrame", username + 1, username));
		initialSettings.put("org.expeditee.gui.folders.FolderSettings.FrameDirs", FolderSettings.FrameDirs);
		initialSettings.put("org.expeditee.gui.folders.FolderSettings.ImageDirs", FolderSettings.ImageDirs);
		initialSettings.put("org.expeditee.gui.folders.FolderSettings.AudioDirs", FolderSettings.AudioDirs);
		
		// Record the credentials frame number
		Map<String, Consumer<Frame>> notifiers = new HashMap<String, Consumer<Frame>>();
		notifiers.put("settings.identity", frame -> {
			AuthenticatorBrowser.CREDENTIALS_FRAME = frame.getNumber();
			frame.addToData("MultiuserCredentials");
			Collection<Text> textItems = frame.getTextItems();
			for (Text t: textItems) {
				if (t.getText().equals("Secrets")) {
					t.setPermission(new PermissionPair(UserAppliedPermission.followLinks, UserAppliedPermission.denied));
					break;
				}
			}
		});
		
		// Create users profile
		Frame profile = FrameIO.CreateNewProfile(username, initialSettings, notifiers);
		int lastNumber = FrameIO.getLastNumber(profile.getFramesetName());
		for (int i = 1; i <= lastNumber; i++) {
			Frame f = FrameIO.LoadFrame(profile.getFramesetName() + i);
			Text titleItem = f.getTitleItem();
			if (i == 1 && titleItem != null) {
				titleItem.delete();
				f.setBackgroundColor(new Colour(1, 1, 0.39f));
			}
			f.setOwner(username);
			f.getAllItems().stream().forEach(item -> item.setOwner(username));
			f.setChanged(true);
			if (f.getNumber() != AuthenticatorBrowser.CREDENTIALS_FRAME) {
				f.setEncryptionLabel(AuthenticatorBrowser.PROFILEENCRYPTIONLABEL);
			}
			Collection<Item> secretsLink = Actions.getByContent(f, "Secrets");
			Collection<Item> publicKeyItem = Actions.getByContent(f, "PublicKey");
			if (!secretsLink.isEmpty() && !publicKeyItem.isEmpty()) {
				//Then we are on credentials frame
				f.addToData("MultiuserCredentials");
			}
			Text backupPersonalKey = KeyList.PersonalKey.get();
			Text tempPersonalKey = KeyList.PersonalKey.generateText();
			tempPersonalKey.setData(personalKey);
			KeyList.PersonalKey.setSetting(tempPersonalKey);
			FrameIO.SaveFrame(f);
			KeyList.PersonalKey.setSetting(backupPersonalKey);
		}
		
		if (AuthenticatorBrowser.CREDENTIALS_FRAME == -1) {
			System.err.println("authActions::Unable to establish credentials frame for new profile frame.  Account creation failed.");
			return;
		}
		
		try {
			progressBar.UpdateMessage(message + "Establishing user credentials.", progress += step);
		} catch (Exception e) {
			e.printStackTrace();
		}
		DisplayController.refreshBayArea();
				
		// Create credentials
		File credentialsDir = new File(profile.getFramesetPath() + username + "-credentials");
		credentialsDir.mkdir();
		// 	credentials.inf file.
		String credentialsPath =  credentialsDir.getAbsolutePath() + File.separator + "credentials.inf";
		File credentialsFile = new File(credentialsPath);
		credentialsFile.createNewFile();
		FileWriter out = new FileWriter(credentialsFile);
		out.write(AuthenticatorBrowser.CREDENTIALS_FRAME + ".exp");
		out.flush();
		out.close();
		//	migrate credentials frame
		Frame credentialsFrame = FrameIO.LoadFrame(username + AuthenticatorBrowser.CREDENTIALS_FRAME);
		Path destinationDirectory = Paths.get(credentialsDir.getAbsolutePath());
		Path destinationFile = destinationDirectory.resolve(AuthenticatorBrowser.CREDENTIALS_FRAME + ExpReader.EXTENTION);
		FrameIO.migrateFrame(credentialsFrame, destinationFile);

		try {
			progressBar.UpdateMessage(message + "Creating Individual Space.", progress += step);
		} catch (Exception e) {
			e.printStackTrace();
		}
		DisplayController.refreshBayArea();
		
		// Copy private resources to personal area
		Path personalResources = UserSettings.PublicAndPrivateResources ? FrameIO.setupPersonalResources(username) : Paths.get(FrameIO.PARENT_FOLDER);
		
		File contactsDir = new File(personalResources.resolve("contacts").toAbsolutePath().toString());
		contactsDir.mkdir();

		try {
			progressBar.UpdateMessage(message + "Creating Space For Dead Drops.", progress += step);
		} catch (Exception e) {
			e.printStackTrace();
		}
		DisplayController.refreshBayArea();
		
		File deadDropsDir = new File(personalResources.resolve("deaddrops").toAbsolutePath().toString());
		deadDropsDir.mkdir();
		
		System.err.println("**** Hardwired call in Apollo's AuthioPathManager");
		AudioPathManager.activateAndScanAudioDir(); // ****
		
		try {
			progressBar.UpdateMessage(message + "Done.", 100);
		} catch (Exception e) {
			e.printStackTrace();
		}
		DisplayController.refreshBayArea();
	}
	
	private static TextSetting constructTextSetting(String tooltip, String text, String data) {
		return new TextSetting(tooltip, text) {
			@Override
			public Text generateText() {
				Text t = new Text(text);
				t.setData(data);
				return t;
			}
		};
	}

	private static <T> GenericSetting<T> constructGenericSetting(Class<T> type, String tooltip, String name, T value, String frameset) {
		return new GenericSetting<T>(type, tooltip, name, value) {
			@Override
			public Text generateRepresentation(String name, String frameset) {
				Text t = new Text(name + ": " + value);
				return t;
			}
		};
	}
}