/* -*- Mode: Java; c-basic-offset: 4; tab-width: 4; indent-tabs-mode: nil; -*-
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

package org.mozilla.gecko;

import org.mozilla.gecko.util.GeckoEventListener;

import org.json.JSONArray;
import org.json.JSONObject;

import android.app.AlertDialog;
import android.app.Dialog;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.preference.CheckBoxPreference;
import android.preference.EditTextPreference;
import android.preference.ListPreference;
import android.preference.Preference;
import android.preference.Preference.OnPreferenceChangeListener;
import android.preference.PreferenceActivity;
import android.preference.PreferenceGroup;
import android.preference.PreferenceManager;
import android.preference.PreferenceScreen;
import android.text.Editable;
import android.text.InputType;
import android.text.TextUtils;
import android.text.TextWatcher;
import android.util.Log;
import android.view.MenuItem;
import android.view.View;
import android.widget.EditText;
import android.widget.LinearLayout;
import android.widget.Toast;

import java.util.ArrayList;

public class GeckoPreferences
    extends PreferenceActivity
    implements OnPreferenceChangeListener, GeckoEventListener
{
    private static final String LOGTAG = "GeckoPreferences";

    private ArrayList<String> mPreferencesList;
    private PreferenceScreen mPreferenceScreen;
    private static boolean sIsCharEncodingEnabled = false;
    private static final String NON_PREF_PREFIX = "android.not_a_preference.";

    // These match keys in resources/xml/preferences.xml.in.
    public static String PREFS_MP_ENABLED         = "privacy.masterpassword.enabled";
    public static String PREFS_MENU_CHAR_ENCODING = "browser.menu.showCharacterEncoding";
    public static String PREFS_ANNOUNCEMENTS_ENABLED = NON_PREF_PREFIX + "privacy.announcements.enabled";
    public static String PREFS_UPDATER_AUTODOWNLOAD  = "app.update.autodownload";

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        addPreferencesFromResource(R.xml.preferences);
        registerEventListener("Sanitize:Finished");
    }

    @Override
    public void onWindowFocusChanged(boolean hasFocus) {
        if (!hasFocus)
            return;

        mPreferencesList = new ArrayList<String>();
        mPreferenceScreen = getPreferenceScreen();
        initGroups(mPreferenceScreen);
        initValues();
    }

    @Override
    protected void onDestroy() {
        super.onDestroy();
        unregisterEventListener("Sanitize:Finished");
    }

    public void handleMessage(String event, JSONObject message) {
        try {
            if (event.equals("Sanitize:Finished")) {
                boolean success = message.getBoolean("success");
                final int stringRes = success ? R.string.private_data_success : R.string.private_data_fail;
                final Context context = this;
                GeckoAppShell.getMainHandler().post(new Runnable () {
                    public void run() {
                        Toast.makeText(context, stringRes, Toast.LENGTH_SHORT).show();
                    }
                });
            }
        } catch (Exception e) {
            Log.e(LOGTAG, "Exception handling message \"" + event + "\":", e);
        }
    }

    private void initGroups(PreferenceGroup preferences) {
        final int count = preferences.getPreferenceCount();
        for (int i = 0; i < count; i++) {
            Preference pref = preferences.getPreference(i);
            if (pref instanceof PreferenceGroup)
                initGroups((PreferenceGroup)pref);
            else {
                pref.setOnPreferenceChangeListener(this);

                // Some Preference UI elements are not actually preferences,
                // but they require a key to work correctly. For example,
                // "Clear private data" requires a key for its state to be
                // saved when the orientation changes. It uses the
                // "android.not_a_preference.privacy.clear" key - which doesn't
                // exist in Gecko - to satisfy this requirement.
                String key = pref.getKey();
                if (key != null && !key.startsWith(NON_PREF_PREFIX)) {
                    mPreferencesList.add(pref.getKey());
                }
            }
        }
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case android.R.id.home:
                finish();
                return true;
        }

        return super.onOptionsItemSelected(item);
    }

    final private int DIALOG_CREATE_MASTER_PASSWORD = 0;
    final private int DIALOG_REMOVE_MASTER_PASSWORD = 1;

    public static void setCharEncodingState(boolean enabled) {
        sIsCharEncodingEnabled = enabled;
    }

    public static boolean getCharEncodingState() {
        return sIsCharEncodingEnabled;
    }

    /**
     * Broadcast an intent with <code>pref</code>, <code>branch</code>, and
     * <code>enabled</code> extras. This is intended to represent the
     * notification of a preference value to observers.
     */
    public static void broadcastPrefAction(final Context context,
                                           final String action,
                                           final String pref,
                                           final boolean value) {
        final Intent intent = new Intent(action);
        intent.setAction(action);
        intent.putExtra("pref", pref);
        intent.putExtra("branch", GeckoApp.PREFS_NAME);
        intent.putExtra("enabled", value);
        Log.d(LOGTAG, "Broadcast: " + action + ", " + pref + ", " + GeckoApp.PREFS_NAME + ", " + value);
        context.sendBroadcast(intent);
    }

    /**
     * Broadcast the provided value as the value of the
     * <code>PREFS_ANNOUNCEMENTS_ENABLED</code> pref.
     */
    public static void broadcastAnnouncementsPref(final Context context, final boolean value) {
        broadcastPrefAction(context,
                            GeckoApp.ACTION_ANNOUNCEMENTS_PREF,
                            PREFS_ANNOUNCEMENTS_ENABLED,
                            value);
    }

    /**
     * Broadcast the current value of the
     * <code>PREFS_ANNOUNCEMENTS_ENABLED</code> pref.
     */
    public static void broadcastAnnouncementsPref(final Context context) {
        broadcastPrefAction(context,
                            GeckoApp.ACTION_ANNOUNCEMENTS_PREF,
                            PREFS_ANNOUNCEMENTS_ENABLED,
                            getBooleanPref(context, PREFS_ANNOUNCEMENTS_ENABLED, true));
    }

    /**
     * Return the value of the named preference in the default preferences file.
     *
     * This corresponds to the storage that backs preferences.xml.
     * @param context a <code>Context</code>; the
     *                <code>PreferenceActivity</code> will suffice, but this
     *                method is intended to be called from other contexts
     *                within the application, not just this <code>Activity</code>.
     * @param name    the name of the preference to retrieve.
     * @param def     the default value to return if the preference is not present.
     * @return        the value of the preference, or the default.
     */
    public static boolean getBooleanPref(final Context context, final String name, boolean def) {
        final SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(context);
        return prefs.getBoolean(name, def);
    }

    @Override
    public boolean onPreferenceChange(Preference preference, Object newValue) {
        String prefName = preference.getKey();
        if (prefName != null && prefName.equals(PREFS_MP_ENABLED)) {
            showDialog((Boolean) newValue ? DIALOG_CREATE_MASTER_PASSWORD : DIALOG_REMOVE_MASTER_PASSWORD);
            return false;
        } else if (prefName != null && prefName.equals(PREFS_MENU_CHAR_ENCODING)) {
            setCharEncodingState(((String) newValue).equals("true"));
        } else if (prefName != null && prefName.equals(PREFS_ANNOUNCEMENTS_ENABLED)) {
            // Send a broadcast intent to the product announcements service, either to start or
            // to stop the repeated background checks.
            broadcastAnnouncementsPref(GeckoApp.mAppContext, ((Boolean) newValue).booleanValue());
        } else if (prefName != null && prefName.equals(PREFS_UPDATER_AUTODOWNLOAD)) {
            org.mozilla.gecko.updater.UpdateServiceHelper.registerForUpdates(GeckoApp.mAppContext, (String)newValue);
        }

        if (!TextUtils.isEmpty(prefName)) {
            PrefsHelper.setPref(prefName, newValue);
        }
        if (preference instanceof ListPreference) {
            // We need to find the entry for the new value
            int newIndex = ((ListPreference)preference).findIndexOfValue((String) newValue);
            CharSequence newEntry = ((ListPreference)preference).getEntries()[newIndex];
            ((ListPreference)preference).setSummary(newEntry);
        } else if (preference instanceof LinkPreference) {
            finish();
        } else if (preference instanceof FontSizePreference) {
            final FontSizePreference fontSizePref = (FontSizePreference) preference;
            fontSizePref.setSummary(fontSizePref.getSavedFontSizeName());
        }
        return true;
    }

    private EditText getTextBox(int aHintText) {
        EditText input = new EditText(GeckoApp.mAppContext);
        int inputtype = InputType.TYPE_CLASS_TEXT;
        inputtype |= InputType.TYPE_TEXT_VARIATION_PASSWORD | InputType.TYPE_TEXT_FLAG_NO_SUGGESTIONS;
        input.setInputType(inputtype);

        String hint = getResources().getString(aHintText);
        input.setHint(aHintText);
        return input;
    }

    private class PasswordTextWatcher implements TextWatcher {
        EditText input1 = null;
        EditText input2 = null;
        AlertDialog dialog = null;

        PasswordTextWatcher(EditText aInput1, EditText aInput2, AlertDialog aDialog) {
            input1 = aInput1;
            input2 = aInput2;
            dialog = aDialog;
        }

        public void afterTextChanged(Editable s) {
            if (dialog == null)
                return;

            String text1 = input1.getText().toString();
            String text2 = input2.getText().toString();
            boolean disabled = TextUtils.isEmpty(text1) || TextUtils.isEmpty(text2) || !text1.equals(text2);
            dialog.getButton(DialogInterface.BUTTON_POSITIVE).setEnabled(!disabled);
        }

        public void beforeTextChanged(CharSequence s, int start, int count, int after) { }
        public void onTextChanged(CharSequence s, int start, int before, int count) { }
    }

    protected Dialog onCreateDialog(int id) {
        AlertDialog.Builder builder = new AlertDialog.Builder(this);
        LinearLayout linearLayout = new LinearLayout(this);
        linearLayout.setOrientation(LinearLayout.VERTICAL);
        AlertDialog dialog = null;
        switch(id) {
            case DIALOG_CREATE_MASTER_PASSWORD:
                final EditText input1 = getTextBox(R.string.masterpassword_password);
                final EditText input2 = getTextBox(R.string.masterpassword_confirm);
                linearLayout.addView(input1);
                linearLayout.addView(input2);

                builder.setTitle(R.string.masterpassword_create_title)
                       .setView((View)linearLayout)
                       .setPositiveButton(R.string.button_ok, new DialogInterface.OnClickListener() {  
                            public void onClick(DialogInterface dialog, int which) {
                                JSONObject jsonPref = new JSONObject();
                                try {
                                    jsonPref.put("name", PREFS_MP_ENABLED);
                                    jsonPref.put("type", "string");
                                    jsonPref.put("value", input1.getText().toString());
                    
                                    GeckoEvent event = GeckoEvent.createBroadcastEvent("Preferences:Set", jsonPref.toString());
                                    GeckoAppShell.sendEventToGecko(event);
                                } catch(Exception ex) {
                                    Log.e(LOGTAG, "Error setting master password", ex);
                                }
                                return;
                            }
                        })
                        .setNegativeButton(R.string.button_cancel, new DialogInterface.OnClickListener() {  
                            public void onClick(DialogInterface dialog, int which) {
                                return;
                            }
                        });
                        dialog = builder.create();
                        dialog.setOnShowListener(new DialogInterface.OnShowListener() {
                            public void onShow(DialogInterface dialog) {
                                input1.setText("");
                                input2.setText("");
                                input1.requestFocus();
                            }
                        });

                        PasswordTextWatcher watcher = new PasswordTextWatcher(input1, input2, dialog);
                        input1.addTextChangedListener((TextWatcher)watcher);
                        input2.addTextChangedListener((TextWatcher)watcher);

                break;
            case DIALOG_REMOVE_MASTER_PASSWORD:
                final EditText input = getTextBox(R.string.masterpassword_password);
                linearLayout.addView(input);

                builder.setTitle(R.string.masterpassword_remove_title)
                       .setView((View)linearLayout)
                       .setPositiveButton(R.string.button_ok, new DialogInterface.OnClickListener() {  
                            public void onClick(DialogInterface dialog, int which) {
                                PrefsHelper.setPref(PREFS_MP_ENABLED, input.getText().toString());
                            }
                        })
                        .setNegativeButton(R.string.button_cancel, new DialogInterface.OnClickListener() {  
                            public void onClick(DialogInterface dialog, int which) {
                                return;
                            }
                        });
                        dialog = builder.create();
                        dialog.setOnDismissListener(new DialogInterface.OnDismissListener() {
                            public void onDismiss(DialogInterface dialog) {
                                input.setText("");
                            }
                        });
                break;
            default:
                return null;
        }

        return dialog;
    }

    // Initialize preferences by requesting the preference values from Gecko
    private void initValues() {
        JSONArray jsonPrefs = new JSONArray(mPreferencesList);
        PrefsHelper.getPrefs(jsonPrefs, new PrefsHelper.PrefHandlerBase() {
            private Preference getField(String prefName) {
                return (mPreferenceScreen == null ? null : mPreferenceScreen.findPreference(prefName));
            }

            @Override public void prefValue(String prefName, final boolean value) {
                final Preference pref = getField(prefName);
                if (pref instanceof CheckBoxPreference) {
                    GeckoAppShell.getMainHandler().post(new Runnable() {
                        public void run() {
                            if (((CheckBoxPreference)pref).isChecked() != value)
                                ((CheckBoxPreference)pref).setChecked(value);
                        }
                    });
                }
            }

            @Override public void prefValue(String prefName, final String value) {
                final Preference pref = getField(prefName);
                if (pref instanceof EditTextPreference) {
                    GeckoAppShell.getMainHandler().post(new Runnable() {
                        public void run() {
                            ((EditTextPreference)pref).setText(value);
                        }
                    });
                } else if (pref instanceof ListPreference) {
                    GeckoAppShell.getMainHandler().post(new Runnable() {
                        public void run() {
                            ((ListPreference)pref).setValue(value);
                            // Set the summary string to the current entry
                            CharSequence selectedEntry = ((ListPreference)pref).getEntry();
                            ((ListPreference)pref).setSummary(selectedEntry);
                        }
                    });
                } else if (pref instanceof FontSizePreference) {
                    final FontSizePreference fontSizePref = (FontSizePreference) pref;
                    fontSizePref.setSavedFontSize(value);
                    final String fontSizeName = fontSizePref.getSavedFontSizeName();
                    GeckoAppShell.getMainHandler().post(new Runnable() {
                        public void run() {
                            fontSizePref.setSummary(fontSizeName); // Ex: "Small".
                        }
                    });
                }
            }

            @Override public void finish() {
                // enable all preferences once we have them from gecko
                GeckoAppShell.getMainHandler().post(new Runnable() {
                    public void run() {
                        mPreferenceScreen.setEnabled(true);
                    }
                });
            }
        });
    }

    private void registerEventListener(String event) {
        GeckoAppShell.getEventDispatcher().registerEventListener(event, this);
    }

    private void unregisterEventListener(String event) {
        GeckoAppShell.getEventDispatcher().unregisterEventListener(event, this);
    }
}