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 2018-2022 by Marcel Bokhorst (M66B)
*/

import static android.app.Activity.RESULT_OK;

import android.Manifest;
import android.content.ContentResolver;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.net.Uri;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Toast;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.appcompat.widget.SearchView;
import androidx.constraintlayout.widget.Group;
import androidx.core.view.MenuCompat;
import androidx.fragment.app.FragmentTransaction;
import androidx.lifecycle.Lifecycle;
import androidx.lifecycle.LifecycleObserver;
import androidx.lifecycle.Observer;
import androidx.lifecycle.OnLifecycleEvent;
import androidx.preference.PreferenceManager;
import androidx.recyclerview.widget.DividerItemDecoration;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;

import com.google.android.material.floatingactionbutton.FloatingActionButton;

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

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Date;
import java.util.List;

public class FragmentRules extends FragmentBase {
    private long account;
    private int protocol;
    private long folder;
    private String type;

    private boolean cards;

    private RecyclerView rvRule;
    private ContentLoadingProgressBar pbWait;
    private Group grpReady;
    private FloatingActionButton fab;

    private String searching = null;
    private AdapterRule adapter;

    private static final int REQUEST_EXPORT = 1;
    private static final int REQUEST_IMPORT = 2;
    static final int REQUEST_MOVE = 3;
    private static final int REQUEST_CLEAR = 4;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Get arguments
        Bundle args = getArguments();
        account = args.getLong("account", -1);
        protocol = args.getInt("protocol", -1);
        folder = args.getLong("folder", -1);
        type = args.getString("type");

        SharedPreferences prefs = PreferenceManager.getDefaultSharedPreferences(getContext());
        cards = prefs.getBoolean("cards", true);
    }

    @Override
    @Nullable
    public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        setSubtitle(R.string.title_edit_rules);
        setHasOptionsMenu(true);

        View view = inflater.inflate(R.layout.fragment_rules, container, false);

        // Get controls
        rvRule = view.findViewById(R.id.rvRule);
        pbWait = view.findViewById(R.id.pbWait);
        grpReady = view.findViewById(R.id.grpReady);
        fab = view.findViewById(R.id.fab);

        // Wire controls

        rvRule.setHasFixedSize(true);
        LinearLayoutManager llm = new LinearLayoutManager(getContext());
        rvRule.setLayoutManager(llm);

        adapter = new AdapterRule(this);
        rvRule.setAdapter(adapter);

        if (!cards) {
            DividerItemDecoration itemDecorator = new DividerItemDecoration(getContext(), llm.getOrientation());
            itemDecorator.setDrawable(getContext().getDrawable(R.drawable.divider));
            rvRule.addItemDecoration(itemDecorator);
        }

        fab.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                Bundle args = new Bundle();
                args.putLong("account", account);
                args.putInt("protocol", protocol);
                args.putLong("folder", folder);

                FragmentRule fragment = new FragmentRule();
                fragment.setArguments(args);

                FragmentTransaction fragmentTransaction = getParentFragmentManager().beginTransaction();
                fragmentTransaction.replace(R.id.content_frame, fragment).addToBackStack("rule");
                fragmentTransaction.commit();
            }
        });

        // Initialize

        FragmentDialogTheme.setBackground(getContext(), view, false);
        grpReady.setVisibility(View.GONE);
        pbWait.setVisibility(View.VISIBLE);

        return view;
    }

    @Override
    public void onSaveInstanceState(Bundle outState) {
        outState.putString("fair:searching", searching);
        super.onSaveInstanceState(outState);
    }

    @Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);

        if (savedInstanceState != null)
            searching = savedInstanceState.getString("fair:searching");
        adapter.search(searching);

        DB db = DB.getInstance(getContext());
        db.rule().liveRules(folder).observe(getViewLifecycleOwner(), new Observer<List<TupleRuleEx>>() {
            @Override
            public void onChanged(List<TupleRuleEx> rules) {
                if (rules == null)
                    rules = new ArrayList<>();

                adapter.set(protocol, rules);

                pbWait.setVisibility(View.GONE);
                grpReady.setVisibility(View.VISIBLE);
            }
        });
    }

    @Override
    public void onActivityResult(int requestCode, int resultCode, @Nullable Intent data) {
        super.onActivityResult(requestCode, resultCode, data);

        try {
            switch (requestCode) {
                case REQUEST_EXPORT:
                    if (resultCode == RESULT_OK && data != null)
                        onExport(data);
                    break;
                case REQUEST_IMPORT:
                    if (resultCode == RESULT_OK && data != null)
                        onImport(data);
                    break;
                case REQUEST_MOVE:
                    if (resultCode == RESULT_OK && data != null)
                        onMove(data.getBundleExtra("args"));
                    break;
                case REQUEST_CLEAR:
                    if (resultCode == RESULT_OK && data != null)
                        onClear(data.getBundleExtra("args"));
                    break;
            }
        } catch (Throwable ex) {
            Log.e(ex);
        }
    }

    @Override
    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
        inflater.inflate(R.menu.menu_rules, menu);

        MenuItem menuSearch = menu.findItem(R.id.menu_search);
        SearchView searchView = (SearchView) menuSearch.getActionView();
        searchView.setQueryHint(getString(R.string.title_rules_search_hint));

        if (!TextUtils.isEmpty(searching)) {
            menuSearch.expandActionView();
            searchView.setQuery(searching, true);
        }

        getViewLifecycleOwner().getLifecycle().addObserver(new LifecycleObserver() {
            @OnLifecycleEvent(Lifecycle.Event.ON_DESTROY)
            public void onDestroyed() {
                menuSearch.collapseActionView();
                getViewLifecycleOwner().getLifecycle().removeObserver(this);
            }
        });

        searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
            @Override
            public boolean onQueryTextChange(String newText) {
                if (getView() != null) {
                    searching = newText;
                    adapter.search(newText);
                }
                return true;
            }

            @Override
            public boolean onQueryTextSubmit(String query) {
                searching = query;
                adapter.search(query);
                return true;
            }
        });

        MenuCompat.setGroupDividerEnabled(menu, true);

        super.onCreateOptionsMenu(menu, inflater);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int itemId = item.getItemId();
        if (itemId == R.id.menu_export) {
            onMenuExport();
            return true;
        } else if (itemId == R.id.menu_import) {
            onMenuImport();
            return true;
        } else if (itemId == R.id.menu_delete_all) {
            onMenuDelete();
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    private void onMenuExport() {
        if (!ActivityBilling.isPro(getContext())) {
            startActivity(new Intent(getContext(), ActivityBilling.class));
            return;
        }

        Intent intent = new Intent(Intent.ACTION_CREATE_DOCUMENT);
        intent.addCategory(Intent.CATEGORY_OPENABLE);
        intent.setType("*/*");
        intent.putExtra(Intent.EXTRA_TITLE, "fairemail_" +
                new SimpleDateFormat("yyyyMMdd").format(new Date().getTime()) + ".rules");
        Helper.openAdvanced(intent);
        startActivityForResult(intent, REQUEST_EXPORT);
    }

    private void onMenuImport() {
        Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
        intent.addCategory(Intent.CATEGORY_OPENABLE);
        intent.setType("*/*");
        startActivityForResult(intent, REQUEST_IMPORT);
    }

    private void onMenuDelete() {
        Bundle aargs = new Bundle();
        aargs.putString("question", getString(R.string.title_rules_delete_all_confirm));
        aargs.putLong("folder", folder);

        FragmentDialogAsk ask = new FragmentDialogAsk();
        ask.setArguments(aargs);
        ask.setTargetFragment(this, REQUEST_CLEAR);
        ask.show(getParentFragmentManager(), "rules:clear");
    }

    private void onExport(Intent data) {
        Bundle args = new Bundle();
        args.putLong("folder", folder);
        args.putParcelable("uri", data.getData());

        new SimpleTask<Void>() {
            @Override
            protected void onPreExecute(Bundle args) {
                ToastEx.makeText(getContext(), R.string.title_executing, Toast.LENGTH_LONG).show();
            }

            @Override
            protected Void onExecute(Context context, Bundle args) throws Throwable {
                long fid = args.getLong("folder");
                Uri uri = args.getParcelable("uri");

                if (uri == null)
                    throw new FileNotFoundException();

                if (!"content".equals(uri.getScheme())) {
                    Log.w("Export uri=" + uri);
                    throw new IllegalArgumentException(context.getString(R.string.title_no_stream));
                }

                DB db = DB.getInstance(context);
                JSONArray jrules = new JSONArray();
                for (EntityRule rule : db.rule().getRules(fid)) {
                    JSONObject jaction = new JSONObject(rule.action);

                    int type = jaction.getInt("type");
                    if (type == EntityRule.TYPE_MOVE || type == EntityRule.TYPE_COPY) {
                        long target = jaction.optLong("target", -1);
                        EntityFolder f = db.folder().getFolder(target);
                        if (f != null)
                            jaction.put("folderType", f.type);
                    }

                    rule.action = jaction.toString();

                    jrules.put(rule.toJSON());
                }

                ContentResolver resolver = context.getContentResolver();
                try (OutputStream os = resolver.openOutputStream(uri)) {
                    Log.i("Writing URI=" + uri);
                    os.write(jrules.toString(2).getBytes());
                }

                return null;
            }

            @Override
            protected void onExecuted(Bundle args, Void data) {
                ToastEx.makeText(getContext(), R.string.title_completed, Toast.LENGTH_LONG).show();
            }

            @Override
            protected void onException(Bundle args, Throwable ex) {
                if (ex instanceof IllegalArgumentException ||
                        ex instanceof FileNotFoundException)
                    ToastEx.makeText(getContext(), ex.getMessage(), Toast.LENGTH_LONG).show();
                else
                    Log.unexpectedError(getParentFragmentManager(), ex);
            }
        }.execute(this, args, "rules:export");
    }

    private void onImport(Intent data) {
        Bundle args = new Bundle();
        args.putLong("folder", folder);
        args.putParcelable("uri", data.getData());

        new SimpleTask<Void>() {
            @Override
            protected void onPreExecute(Bundle args) {
                ToastEx.makeText(getContext(), R.string.title_executing, Toast.LENGTH_LONG).show();
            }

            @Override
            protected Void onExecute(Context context, Bundle args) throws Throwable {
                long fid = args.getLong("folder");
                Uri uri = args.getParcelable("uri");

                if (uri == null)
                    throw new FileNotFoundException();

                if (!"content".equals(uri.getScheme()) &&
                        !Helper.hasPermission(context, Manifest.permission.READ_EXTERNAL_STORAGE)) {
                    Log.w("Import uri=" + uri);
                    throw new IllegalArgumentException(context.getString(R.string.title_no_stream));
                }

                StringBuilder data = new StringBuilder();

                Log.i("Reading URI=" + uri);
                ContentResolver resolver = context.getContentResolver();
                try (InputStream is = resolver.openInputStream(uri)) {
                    BufferedReader reader = new BufferedReader(new InputStreamReader(is));
                    String line;
                    while ((line = reader.readLine()) != null)
                        data.append(line);
                }

                JSONArray jrules = new JSONArray(data.toString());

                DB db = DB.getInstance(context);
                try {
                    db.beginTransaction();

                    EntityFolder folder = db.folder().getFolder(fid);
                    if (folder == null)
                        return null;

                    for (int i = 0; i < jrules.length(); i++) {
                        JSONObject jrule = jrules.getJSONObject(i);
                        EntityRule rule = EntityRule.fromJSON(jrule);

                        JSONObject jaction = new JSONObject(rule.action);

                        int type = jaction.getInt("type");
                        if (type == EntityRule.TYPE_MOVE || type == EntityRule.TYPE_COPY) {
                            String folderType = jaction.optString("folderType");
                            if (!EntityFolder.SYSTEM.equals(folderType) &&
                                    !EntityFolder.USER.equals(folderType)) {
                                EntityFolder f = db.folder().getFolderByType(folder.account, folderType);
                                if (f != null)
                                    jaction.put("target", f.id);
                            }
                        }

                        rule.action = jaction.toString();

                        rule.folder = fid;
                        rule.applied = 0;
                        rule.last_applied = null;
                        rule.id = db.rule().insertRule(rule);
                    }

                    db.setTransactionSuccessful();
                } finally {
                    db.endTransaction();
                }

                return null;
            }

            @Override
            protected void onExecuted(Bundle args, Void data) {
                ToastEx.makeText(getContext(), R.string.title_completed, Toast.LENGTH_LONG).show();
            }

            @Override
            protected void onException(Bundle args, Throwable ex) {
                if (ex instanceof IllegalArgumentException ||
                        ex instanceof FileNotFoundException ||
                        ex instanceof JSONException)
                    ToastEx.makeText(getContext(), ex.getMessage(), Toast.LENGTH_LONG).show();
                else
                    Log.unexpectedError(getParentFragmentManager(), ex);
            }
        }.execute(this, args, "rules:import");
    }

    private void onMove(Bundle args) {
        new SimpleTask<Void>() {
            @Override
            protected Void onExecute(Context context, Bundle args) {
                long id = args.getLong("rule");
                long folder = args.getLong("folder");

                DB db = DB.getInstance(context);
                db.rule().setRuleFolder(id, folder);
                return null;
            }

            @Override
            protected void onException(Bundle args, Throwable ex) {
                Log.unexpectedError(getParentFragmentManager(), ex);
            }
        }.execute(this, args, "rule:move");
    }

    private void onClear(Bundle args) {
        new SimpleTask<Void>() {
            @Override
            protected Void onExecute(Context context, Bundle args) throws Throwable {
                long fid = args.getLong("folder");

                DB db = DB.getInstance(context);
                try {
                    db.beginTransaction();

                    db.rule().deleteRules(fid);

                    db.setTransactionSuccessful();
                } finally {
                    db.endTransaction();
                }

                return null;
            }

            @Override
            protected void onException(Bundle args, Throwable ex) {
                Log.unexpectedError(getParentFragmentManager(), ex);
            }
        }.execute(this, args, "rules:clear");
    }
}