package org.expeditee.encryption;

import java.util.Base64;
import java.util.Collection;

import org.expeditee.auth.AuthenticatorBrowser;
import org.expeditee.gui.Frame;
import org.expeditee.gui.FrameIO;
import org.expeditee.items.Text;
import org.expeditee.settings.UserSettings;

public class Label {
	
	public static LabelResult resolveKey(String label) {
		String credentialsFrameName = UserSettings.ProfileName.get() + 
				AuthenticatorBrowser.CREDENTIALS_FRAME;
		Frame credentialsFrame = FrameIO.LoadFrame(credentialsFrameName);
		Collection<Text> textItems = credentialsFrame.getTextItems();
		textItems.removeIf(t -> !t.getText().equals("Secrets"));
		textItems.removeIf(t -> !t.hasLink());
		if (textItems.isEmpty()) {
			return LabelResult.ErrorUnableToFindSecretsFrame;
		}
		Text linkToSecretsFrame = textItems.iterator().next();
		if (!linkToSecretsFrame.hasLink()) {
			return LabelResult.ErrorUnableToFindSecretsFrame;
		}
		Frame secretsFrame = FrameIO.LoadFrame(linkToSecretsFrame.getParent().getFramesetName() + linkToSecretsFrame.getLink());
		Collection<Text> labels = secretsFrame.getTextItems();
		labels.removeIf(lbl -> !lbl.getText().equals(label));
		labels.removeIf(lbl -> lbl.getData() == null || lbl.getData().size() == 0);
		if (labels.isEmpty()) {
			return LabelResult.ErrorUnableToFindLabel;
		}
		Text labelItem = labels.iterator().next();
		String data = labelItem.getData().get(0);
		if (data.contains("{")) {
			data = data.substring(data.indexOf('}') + 1).trim();
			LabelResult res = LabelResult.SuccessResolveLabelToPartialKey;
			res.key = Base64.getDecoder().decode(data);
			return res;
		} else {
			try {
				LabelResult res = LabelResult.SuccessResolveLabelToKey;
				res.key = Base64.getDecoder().decode(data);
				return res;
			} catch (IllegalArgumentException e) {
				return LabelResult.ErrorUnableToFindLabel;
			}
		}
	}
	
	public enum LabelResult {
		SuccessResolveLabelToKey, 
		SuccessResolveLabelToPartialKey, 
		ErrorUnableToFindSecretsFrame, 
		ErrorUnableToFindLabel;
		
		public byte[] key;
		
		@Override
		public String toString() {
			switch (this) {
			case SuccessResolveLabelToKey:
				return "Resolved label to key: " + Base64.getEncoder().encodeToString(key);
			case SuccessResolveLabelToPartialKey:
				return "Resolved label to slice of a key: " + Base64.getEncoder().encodeToString(key);
			case ErrorUnableToFindSecretsFrame:
				return "Unable to find your Secrets Frame.";
			case ErrorUnableToFindLabel:
				return "Unable to resolve label to encrypt/decrypt frame.  Label: ";
			}
			
			String message = "Was the list of possible enum results updated without nessasary changes to the toString() function?";
			throw new IllegalArgumentException(message);
		}
	}
}