package eu.faircode.email;

/*
    This file is part of FairEmail.

    FairEmail is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 3 of the License, or
    (at your option) any later version.

    FairEmail is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with FairEmail.  If not, see <http://www.gnu.org/licenses/>.

    Copyright 2018-2021 by Marcel Bokhorst (M66B)
*/

import android.app.Dialog;
import android.content.ActivityNotFoundException;
import android.content.ClipData;
import android.content.ClipboardManager;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.graphics.Paint;
import android.graphics.Typeface;
import android.net.Uri;
import android.os.Bundle;
import android.text.Editable;
import android.text.SpannableStringBuilder;
import android.text.Spanned;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.text.method.LinkMovementMethod;
import android.text.style.ForegroundColorSpan;
import android.util.Pair;
import android.view.KeyEvent;
import android.view.LayoutInflater;
import android.view.View;
import android.view.inputmethod.EditorInfo;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.TextView;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.app.AlertDialog;
import androidx.constraintlayout.widget.Group;
import androidx.core.net.MailTo;
import androidx.core.util.PatternsCompat;
import androidx.preference.PreferenceManager;

import java.net.IDN;
import java.net.InetAddress;
import java.util.Arrays;
import java.util.Collections;
import java.util.List;
import java.util.Locale;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class FragmentDialogOpenLink extends FragmentDialogBase {
    private static final String URI_RESET_OPEN = "https://support.google.com/pixelphone/answer/6271667";

    // https://github.com/newhouse/url-tracking-stripper
    private static final List<String> PARANOID_QUERY = Collections.unmodifiableList(Arrays.asList(
            // https://en.wikipedia.org/wiki/UTM_parameters
            "awt_a", // AWeber
            "awt_l", // AWeber
            "awt_m", // AWeber

            "icid", // Adobe
            "gclid", // Google
            "gclsrc", // Google ads
            "dclid", // DoubleClick (Google)
            "fbclid", // Facebook
            "igshid", // Instagram

            "mc_cid", // MailChimp
            "mc_eid", // MailChimp

            "zanpid", // Zanox (Awin)

            "kclickid" // https://support.freespee.com/hc/en-us/articles/202577831-Kenshoo-integration
    ));

    // https://github.com/snarfed/granary/blob/master/granary/facebook.py#L1789

    private static final List<String> FACEBOOK_WHITELIST_PATH = Collections.unmodifiableList(Arrays.asList(
            "/nd/", "/n/", "/story.php"
    ));

    private static final List<String> FACEBOOK_WHITELIST_QUERY = Collections.unmodifiableList(Arrays.asList(
            "story_fbid", "fbid", "id", "comment_id"
    ));

    private ImageButton ibMore;
    private TextView tvMore;
    private Button btnOwner;
    private ContentLoadingProgressBar pbWait;
    private TextView tvOwnerRemark;
    private TextView tvHost;
    private TextView tvOwner;
    private Group grpOwner;
    private Button btnSettings;
    private TextView tvReset;

    @NonNull
    @Override
    public Dialog onCreateDialog(@Nullable Bundle savedInstanceState) {
        final Uri uri = getArguments().getParcelable("uri");
        String _title = getArguments().getString("title");
        if (_title != null)
            _title = _title.replace("\uFFFC", ""); // Object replacement character
        if (TextUtils.isEmpty(_title))
            _title = null;
        final String title = _title;

        final Context context = getContext();
        final SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);

        // Preload web view
        Helper.customTabsWarmup(context);

        // Process link
        final Uri sanitized;
        if (uri.isOpaque())
            sanitized = uri;
        else {
            Uri s = sanitize(uri);
            sanitized = (s == null ? uri : s);
        }

        // Process title
        final Uri uriTitle;
        if (title != null && PatternsCompat.WEB_URL.matcher(title).matches())
            uriTitle = Uri.parse(title.contains("://") ? title : "http://" + title);
        else
            uriTitle = null;

        // Get views
        final View dview = LayoutInflater.from(context).inflate(R.layout.dialog_open_link, null);
        final ImageButton ibInfo = dview.findViewById(R.id.ibInfo);
        final TextView tvTitle = dview.findViewById(R.id.tvTitle);
        final ImageButton ibDifferent = dview.findViewById(R.id.ibDifferent);
        final EditText etLink = dview.findViewById(R.id.etLink);
        final TextView tvLink = dview.findViewById(R.id.tvLink);
        final TextView tvSuspicious = dview.findViewById(R.id.tvSuspicious);
        final TextView tvDisconnect = dview.findViewById(R.id.tvDisconnect);
        final TextView tvDisconnectCategories = dview.findViewById(R.id.tvDisconnectCategories);
        final ImageButton ibShare = dview.findViewById(R.id.ibShare);
        final ImageButton ibCopy = dview.findViewById(R.id.ibCopy);
        final CheckBox cbSecure = dview.findViewById(R.id.cbSecure);
        final CheckBox cbSanitize = dview.findViewById(R.id.cbSanitize);
        final CheckBox cbNotAgain = dview.findViewById(R.id.cbNotAgain);

        ibMore = dview.findViewById(R.id.ibMore);
        tvMore = dview.findViewById(R.id.tvMore);
        btnOwner = dview.findViewById(R.id.btnOwner);
        pbWait = dview.findViewById(R.id.pbWait);
        tvOwnerRemark = dview.findViewById(R.id.tvOwnerRemark);
        tvHost = dview.findViewById(R.id.tvHost);
        tvOwner = dview.findViewById(R.id.tvOwner);
        grpOwner = dview.findViewById(R.id.grpOwner);
        btnSettings = dview.findViewById(R.id.btnSettings);
        tvReset = dview.findViewById(R.id.tvReset);

        final Group grpDifferent = dview.findViewById(R.id.grpDifferent);

        // Wire

        ibInfo.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Helper.viewFAQ(v.getContext(), 35);
            }
        });

        ibDifferent.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                etLink.setText(format(uriTitle, context));
            }
        });

        etLink.addTextChangedListener(new TextWatcher() {
            @Override
            public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {
            }

            @Override
            public void onTextChanged(CharSequence text, int i, int i1, int i2) {
            }

            @Override
            public void afterTextChanged(Editable editable) {
                Uri uri = Uri.parse(editable.toString());

                boolean secure = (!uri.isOpaque() &&
                        "https".equals(uri.getScheme()));
                boolean hyperlink = (!uri.isOpaque() &&
                        ("http".equals(uri.getScheme()) || "https".equals(uri.getScheme())));

                cbSecure.setTag(secure);
                cbSecure.setChecked(secure);

                cbSecure.setText(
                        secure ? R.string.title_link_https : R.string.title_link_http);
                cbSecure.setCompoundDrawablesRelativeWithIntrinsicBounds(
                        0, 0, secure ? 0 : R.drawable.twotone_http_24, 0);
                cbSecure.setTextColor(Helper.resolveColor(context,
                        secure ? android.R.attr.textColorSecondary : R.attr.colorWarning));
                cbSecure.setTypeface(
                        secure ? Typeface.DEFAULT : Typeface.DEFAULT_BOLD);

                cbSecure.setVisibility(hyperlink ? View.VISIBLE : View.GONE);
            }
        });

        etLink.setHorizontallyScrolling(false);
        etLink.setMaxLines(10);
        etLink.setOnEditorActionListener(new TextView.OnEditorActionListener() {
            @Override
            public boolean onEditorAction(TextView v, int actionId, KeyEvent event) {
                if (actionId == EditorInfo.IME_ACTION_DONE) {
                    ((AlertDialog) getDialog()).getButton(DialogInterface.BUTTON_POSITIVE).performClick();
                    return true;
                } else
                    return false;
            }
        });

        ibShare.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent send = new Intent();
                send.setAction(Intent.ACTION_SEND);
                send.putExtra(Intent.EXTRA_TEXT, etLink.getText().toString());
                send.setType("text/plain");
                startActivity(Intent.createChooser(send, title));
            }
        });

        ibCopy.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                ClipboardManager clipboard =
                        (ClipboardManager) context.getSystemService(Context.CLIPBOARD_SERVICE);
                if (clipboard == null)
                    return;

                ClipData clip = ClipData.newPlainText(title, etLink.getText().toString());
                clipboard.setPrimaryClip(clip);

                ToastEx.makeText(context, R.string.title_clipboard_copied, Toast.LENGTH_LONG).show();
            }
        });

        cbSecure.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean checked) {
                boolean tag = (Boolean) compoundButton.getTag();
                if (tag == checked)
                    return;

                Uri uri = Uri.parse(etLink.getText().toString());
                etLink.setText(format(secure(uri, checked), context));
            }
        });

        cbSanitize.setVisibility(uri.equals(sanitized) ? View.GONE : View.VISIBLE);

        cbSanitize.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean checked) {
                etLink.setText(format(secure(checked ? sanitized : uri, cbSecure.isChecked()), context));
            }
        });

        cbNotAgain.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                prefs.edit().putBoolean(uri.getHost() + ".confirm_link", !isChecked).apply();
            }
        });

        View.OnClickListener onMore = new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                setMore(btnOwner.getVisibility() == View.GONE);
            }
        };

        ibMore.setOnClickListener(onMore);
        tvMore.setOnClickListener(onMore);

        btnOwner.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Bundle args = new Bundle();
                args.putParcelable("uri", uri);

                new SimpleTask<Pair<InetAddress, IPInfo.Organization>>() {
                    @Override
                    protected void onPreExecute(Bundle args) {
                        ibMore.setEnabled(false);
                        tvMore.setEnabled(false);
                        btnOwner.setEnabled(false);
                        pbWait.setVisibility(View.VISIBLE);
                        grpOwner.setVisibility(View.GONE);
                    }

                    @Override
                    protected void onPostExecute(Bundle args) {
                        ibMore.setEnabled(true);
                        tvMore.setEnabled(true);
                        btnOwner.setEnabled(true);
                        pbWait.setVisibility(View.GONE);
                        grpOwner.setVisibility(View.VISIBLE);
                    }

                    @Override
                    protected Pair<InetAddress, IPInfo.Organization> onExecute(Context context, Bundle args) throws Throwable {
                        Uri uri = args.getParcelable("uri");
                        return IPInfo.getOrganization(uri, context);
                    }

                    @Override
                    protected void onExecuted(Bundle args, Pair<InetAddress, IPInfo.Organization> data) {
                        tvHost.setText(data.first.toString());
                        tvOwner.setText(data.second.name == null ? "?" : data.second.name);
                        ApplicationEx.getMainHandler().post(new Runnable() {
                            @Override
                            public void run() {
                                dview.scrollTo(0, tvOwner.getBottom());
                            }
                        });
                    }

                    @Override
                    protected void onException(Bundle args, Throwable ex) {
                        tvHost.setText(ex.getClass().getName());
                        tvOwner.setText(ex.getMessage());
                    }
                }.execute(FragmentDialogOpenLink.this, args, "link:owner");
            }
        });

        tvOwnerRemark.setMovementMethod(LinkMovementMethod.getInstance());

        btnSettings.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                Intent privacy = new Intent(v.getContext(), ActivitySetup.class)
                        .setAction("privacy")
                        .setFlags(Intent.FLAG_ACTIVITY_NEW_TASK)
                        .putExtra("tab", "privacy");
                v.getContext().startActivity(privacy);
            }
        });

        tvReset.setPaintFlags(tvReset.getPaintFlags() | Paint.UNDERLINE_TEXT_FLAG);
        tvReset.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Helper.view(view.getContext(), Uri.parse(URI_RESET_OPEN), true);
            }
        });

        // Initialize

        tvTitle.setText(title);
        tvTitle.setVisibility(TextUtils.isEmpty(title) ? View.GONE : View.VISIBLE);

        String host = uri.getHost();
        String thost = (uriTitle == null ? null : uriTitle.getHost());

        String puny = null;
        try {
            if (host != null)
                puny = IDN.toASCII(host, IDN.ALLOW_UNASSIGNED);
        } catch (Throwable ex) {
            Log.i(ex);
            puny = host;
        }

        if (host != null && !host.equals(puny)) {
            etLink.setText(format(uri.buildUpon().encodedAuthority(puny).build(), context));
            tvLink.setText(uri.toString());
            tvSuspicious.setVisibility(View.VISIBLE);
        } else {
            etLink.setText(format(uri, context));
            tvLink.setText(null);
            tvSuspicious.setVisibility(Helper.isSingleScript(host) ? View.GONE : View.VISIBLE);
        }

        if (BuildConfig.DEBUG &&
                tvSuspicious.getVisibility() != View.VISIBLE) {
            Bundle args = new Bundle();
            args.putString("host", host);

            new SimpleTask<Boolean>() {
                @Override
                protected Boolean onExecute(Context context, Bundle args) throws Throwable {
                    String host = args.getString("host");
                    return DnsBlockList.isJunk(context, host);
                }

                @Override
                protected void onExecuted(Bundle args, Boolean blocklist) {
                    if (blocklist != null && blocklist)
                        tvSuspicious.setVisibility(View.VISIBLE);
                }

                @Override
                protected void onException(Bundle args, Throwable ex) {
                    // Ignored
                }
            }.execute(this, args, "link:blocklist");
        }

        grpDifferent.setVisibility(
                host == null || thost == null || host.equalsIgnoreCase(thost)
                        ? View.GONE : View.VISIBLE);

        boolean disconnect_links = prefs.getBoolean("disconnect_links", true);
        List<String> categories = null;
        if (disconnect_links)
            categories = DisconnectBlacklist.getCategories(uri.getHost());
        if (categories != null)
            tvDisconnectCategories.setText(TextUtils.join(", ", categories));
        tvDisconnect.setVisibility(
                categories == null ? View.GONE : View.VISIBLE);
        tvDisconnectCategories.setVisibility(
                categories == null || !BuildConfig.DEBUG ? View.GONE : View.VISIBLE);

        cbNotAgain.setText(context.getString(R.string.title_no_ask_for_again, uri.getHost()));
        cbNotAgain.setVisibility(
                "https".equals(uri.getScheme()) && !TextUtils.isEmpty(uri.getHost())
                        ? View.VISIBLE : View.GONE);

        setMore(false);

        return new AlertDialog.Builder(context)
                .setView(dview)
                .setPositiveButton(android.R.string.ok, new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        Uri uri = Uri.parse(etLink.getText().toString());
                        Helper.view(context, uri, false);
                    }
                })
                .setNeutralButton(R.string.title_browse, new DialogInterface.OnClickListener() {
                    @Override
                    public void onClick(DialogInterface dialog, int which) {
                        // https://developer.android.com/training/basics/intents/sending#AppChooser
                        Uri uri = Uri.parse(etLink.getText().toString());
                        Intent view = new Intent(Intent.ACTION_VIEW, uri);
                        Intent chooser = Intent.createChooser(view, context.getString(R.string.title_select_app));
                        try {
                            startActivity(chooser);
                        } catch (ActivityNotFoundException ex) {
                            Log.w(ex);
                            Helper.view(context, uri, true, true);
                        }
                    }
                })
                .setNegativeButton(android.R.string.cancel, null)
                .create();
    }

    private void setMore(boolean show) {
        ibMore.setImageLevel(show ? 0 : 1);
        btnOwner.setVisibility(show ? View.VISIBLE : View.GONE);
        pbWait.setVisibility(View.GONE);
        tvOwnerRemark.setVisibility(show ? View.VISIBLE : View.GONE);
        grpOwner.setVisibility(View.GONE);
        btnSettings.setVisibility(show ? View.VISIBLE : View.GONE);
        tvReset.setVisibility(show ? View.VISIBLE : View.GONE);
    }

    private static Uri sanitize(Uri uri) {
        boolean changed = false;

        Uri url;
        Uri.Builder builder;
        if (uri.getHost() != null &&
                uri.getHost().endsWith("safelinks.protection.outlook.com") &&
                !TextUtils.isEmpty(uri.getQueryParameter("url"))) {
            changed = true;
            url = Uri.parse(uri.getQueryParameter("url"));
        } else if ("https".equals(uri.getScheme()) &&
                "smex-ctp.trendmicro.com".equals(uri.getHost()) &&
                "/wis/clicktime/v1/query".equals(uri.getPath()) &&
                !TextUtils.isEmpty(uri.getQueryParameter("url"))) {
            changed = true;
            url = Uri.parse(uri.getQueryParameter("url"));
        } else if ("https".equals(uri.getScheme()) &&
                "www.google.com".equals(uri.getHost()) &&
                uri.getPath() != null &&
                uri.getPath().startsWith("/amp/")) {
            // https://blog.amp.dev/2017/02/06/whats-in-an-amp-url/
            Uri result = null;

            String u = uri.toString();
            u = u.replace("https://www.google.com/amp/", "");

            int p = u.indexOf("/");
            while (p > 0) {
                String segment = u.substring(0, p);
                if (segment.contains(".")) {
                    result = Uri.parse("https://" + u);
                    break;
                }

                u = u.substring(p + 1);
                p = u.indexOf("/");
            }

            changed = (result != null);
            url = (result == null ? uri : result);
        } else
            url = uri;

        if (url.isOpaque())
            return uri;

        builder = url.buildUpon();

        builder.clearQuery();
        String host = uri.getHost();
        String path = uri.getPath();
        if (host != null)
            host = host.toLowerCase(Locale.ROOT);
        if (path != null)
            path = path.toLowerCase(Locale.ROOT);
        boolean first = "www.facebook.com".equals(host);
        for (String key : url.getQueryParameterNames()) {
            // https://en.wikipedia.org/wiki/UTM_parameters
            // https://docs.oracle.com/en/cloud/saas/marketing/eloqua-user/Help/EloquaAsynchronousTrackingScripts/EloquaTrackingParameters.htm
            String lkey = key.toLowerCase(Locale.ROOT);
            if (PARANOID_QUERY.contains(lkey) ||
                    lkey.startsWith("utm_") ||
                    lkey.startsWith("elq") ||
                    ((host != null && host.endsWith("facebook.com")) &&
                            !first &&
                            FACEBOOK_WHITELIST_PATH.contains(path) &&
                            !FACEBOOK_WHITELIST_QUERY.contains(lkey)) ||
                    ("store.steampowered.com".equals(host) &&
                            "snr".equals(lkey)))
                changed = true;
            else if (!TextUtils.isEmpty(key))
                for (String value : url.getQueryParameters(key)) {
                    Log.i("Query " + key + "=" + value);
                    Uri suri = Uri.parse(value);
                    if ("http".equals(suri.getScheme()) || "https".equals(suri.getScheme())) {
                        Uri s = sanitize(suri);
                        if (s != null) {
                            changed = true;
                            value = s.toString();
                        }
                    }
                    builder.appendQueryParameter(key, value);
                }
            first = false;
        }

        return (changed ? builder.build() : null);
    }

    private static Uri secure(Uri uri, boolean https) {
        String scheme = uri.getScheme();
        if (https ? "http".equals(scheme) : "https".equals(scheme)) {
            Uri.Builder builder = uri.buildUpon();
            builder.scheme(https ? "https" : "http");

            String authority = uri.getEncodedAuthority();
            if (authority != null) {
                authority = authority.replace(https ? ":80" : ":443", https ? ":443" : ":80");
                builder.encodedAuthority(authority);
            }

            return builder.build();
        } else
            return uri;
    }

    private Spanned format(Uri uri, Context context) {
        String scheme = uri.getScheme();
        String host = uri.getHost();
        String text = uri.toString();
        SpannableStringBuilder ssb = new SpannableStringBuilder(text);

        try {
            int textColorLink = Helper.resolveColor(context, android.R.attr.textColorLink);

            if ("tel".equals(scheme)) {
                // tel://+123%2045%20678%123456
                host = Uri.decode(host);
                text = "tel://" + host;
            } else if ("mailto".equals(scheme)) {
                if (host == null) {
                    MailTo email = MailTo.parse(uri.toString());
                    host = UriHelper.getEmailDomain(email.getTo());
                }
            }

            if (host != null) {
                int index = text.indexOf(host);
                if (index >= 0)
                    ssb.setSpan(new ForegroundColorSpan(textColorLink),
                            index, index + host.length(), Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
            }

            if (uri.isHierarchical())
                for (String name : uri.getQueryParameterNames()) {
                    Pattern pattern = Pattern.compile("[?&]" + Pattern.quote(name) + "=");
                    Matcher matcher = pattern.matcher(text);
                    while (matcher.find()) {
                        ssb.setSpan(new ForegroundColorSpan(textColorLink),
                                matcher.start() + 1, matcher.end() - 1, Spanned.SPAN_EXCLUSIVE_EXCLUSIVE);
                    }
                }
        } catch (Throwable ex) {
            Log.e(ex);
        }

        return ssb;
    }
}