package eu.siacs.conversations.xmpp.pep;

import android.util.Base64;

import java.security.NoSuchAlgorithmException;

import io.ipfs.cid.Cid;

import eu.siacs.conversations.utils.CryptoHelper;
import eu.siacs.conversations.xml.Element;
import eu.siacs.conversations.xmpp.Jid;
import im.conversations.android.xmpp.model.avatar.Metadata;

public class Avatar {

    public enum Origin {
        PEP,
        VCARD
    }

    public String type;
    public String sha1sum;
    public String image;
    public int height;
    public int width;
    public long size;
    public Jid owner;
    public Origin origin = Origin.PEP; // default to maintain compat

    public byte[] getImageAsBytes() {
        return Base64.decode(image, Base64.DEFAULT);
    }

    public String getFilename() {
        return sha1sum;
    }

    public static Avatar parseMetadata(final String primaryId, final Metadata metadata) {
        if (primaryId == null || metadata == null) {
            return null;
        }
        for (Element child : metadata.getChildren()) {
            if (child.getName().equals("info") && primaryId.equals(child.getAttribute("id"))) {
                Avatar avatar = new Avatar();
                String height = child.getAttribute("height");
                String width = child.getAttribute("width");
                String size = child.getAttribute("bytes");
                try {
                    if (height != null) {
                        avatar.height = Integer.parseInt(height);
                    }
                    if (width != null) {
                        avatar.width = Integer.parseInt(width);
                    }
                    if (size != null) {
                        avatar.size = Long.parseLong(size);
                    }
                } catch (NumberFormatException e) {
                    return null;
                }
                avatar.type = child.getAttribute("type");
                String hash = child.getAttribute("id");
                if (!isValidSHA1(hash)) {
                    return null;
                }
                avatar.sha1sum = hash;
                avatar.origin = Origin.PEP;
                return avatar;
            }
        }
        return null;
    }

    @Override
    public boolean equals(Object object) {
        if (object != null && object instanceof Avatar other) {
            return other.getFilename().equals(this.getFilename());
        } else {
            return false;
        }
    }

	public Cid cid() {
		if (sha1sum == null) return null;

		try {
			return CryptoHelper.cid(CryptoHelper.hexToBytes(sha1sum), "sha-1");
		} catch (final NoSuchAlgorithmException e) {
			return null;
		}
	}

	public static Avatar parsePresence(Element x) {
		String hash = x == null ? null : x.findChildContent("photo");
		if (hash == null) {
			return null;
		}
		if (!isValidSHA1(hash)) {
			return null;
		}
		Avatar avatar = new Avatar();
		avatar.sha1sum = hash;
		avatar.origin = Origin.VCARD;
		return avatar;
	}

    private static boolean isValidSHA1(String s) {
        return s != null && s.matches("[a-fA-F0-9]{40}");
    }
}