package com.ts3client.ui;

import javax.swing.BorderFactory;
import javax.swing.Box;
import javax.swing.BoxLayout;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSpinner;
import javax.swing.SpinnerNumberModel;
import java.awt.Color;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/**
 * The channel editor's "Permissions" tab: the needed-power permissions set on the channel
 * itself, which is the subset of channel permissions TeamSpeak surfaces here.
 *
 * <p>These are not channel properties but permissions, so they are read with
 * {@code channelpermlist} and written with {@code channeladdperm}. A power left at zero is
 * not a permission the channel carries: clearing a spinner back to zero removes the
 * permission again so the channel inherits it, which is how the official client behaves.
 */
final class ChannelPermissionsPanel extends JPanel {

    /** The regular powers, in the order the official dialog lists them. */
    private static final String[][] REGULAR = {
            {"i_channel_needed_join_power", "Join:"},
            {"i_channel_needed_subscribe_power", "Subscribe:"},
            {"i_channel_needed_description_view_power", "Desc. View:"},
            {"i_channel_needed_modify_power", "Modify:"},
            {"i_channel_needed_delete_power", "Delete:"}};

    private static final String[][] FILE_TRANSFER = {
            {"i_ft_needed_file_browse_power", "Browse:"},
            {"i_ft_needed_file_upload_power", "Upload:"},
            {"i_ft_needed_file_download_power", "Download:"},
            {"i_ft_needed_file_rename_power", "Rename:"},
            {"i_ft_needed_directory_create_power", "Dir. Create:"}};

    private final Map<String, JSpinner> spinners = new LinkedHashMap<>();
    /** The values the server reported, to tell an edited power from an untouched one. */
    private final Map<String, Integer> original = new LinkedHashMap<>();
    private final JLabel status = new JLabel(" ");

    ChannelPermissionsPanel() {
        setLayout(new BoxLayout(this, BoxLayout.Y_AXIS));
        setBorder(BorderFactory.createEmptyBorder(8, 8, 8, 8));

        JPanel groups = new JPanel();
        groups.setLayout(new BoxLayout(groups, BoxLayout.X_AXIS));
        groups.add(group("Regular Needed Powers", REGULAR));
        groups.add(Box.createHorizontalStrut(8));
        groups.add(group("File Transfer Needed Powers", FILE_TRANSFER));
        groups.setAlignmentX(0f);
        add(groups);

        status.setAlignmentX(0f);
        status.setBorder(BorderFactory.createEmptyBorder(6, 2, 0, 2));
        add(status);
        add(Box.createVerticalGlue());
        setEditable(false);
    }

    /** Fills the spinners from a {@code channelpermlist} result and enables editing. */
    void read(Map<String, Integer> permissions) {
        original.clear();
        for (Map.Entry<String, JSpinner> entry : spinners.entrySet()) {
            int value = permissions.getOrDefault(entry.getKey(), 0);
            original.put(entry.getKey(), value);
            entry.getValue().setValue(value);
        }
        setEditable(true);
        setStatus(" ", false);
    }

    /** Greys the tab out with a reason, e.g. when the server refuses to show the permissions. */
    void showUnavailable(String message) {
        setEditable(false);
        setStatus(message, true);
    }

    /** The permissions whose power was changed to a non-zero value. */
    Map<String, Integer> changed() {
        Map<String, Integer> changed = new LinkedHashMap<>();
        for (Map.Entry<String, JSpinner> entry : spinners.entrySet()) {
            int value = (Integer) entry.getValue().getValue();
            if (value != 0 && value != original.getOrDefault(entry.getKey(), 0)) {
                changed.put(entry.getKey(), value);
            }
        }
        return changed;
    }

    /** The permissions cleared back to zero, which are removed from the channel. */
    List<String> cleared() {
        List<String> cleared = new ArrayList<>();
        for (Map.Entry<String, JSpinner> entry : spinners.entrySet()) {
            int value = (Integer) entry.getValue().getValue();
            if (value == 0 && original.getOrDefault(entry.getKey(), 0) != 0) cleared.add(entry.getKey());
        }
        return cleared;
    }

    void setStatus(String message, boolean error) {
        status.setText(message == null || message.isEmpty() ? " " : message);
        status.setForeground(error ? Color.RED.darker() : Theme.chatSystem());
    }

    private void setEditable(boolean editable) {
        for (JSpinner spinner : spinners.values()) spinner.setEnabled(editable);
    }

    private JPanel group(String title, String[][] permissions) {
        JPanel panel = new JPanel(new GridBagLayout());
        panel.setBorder(BorderFactory.createTitledBorder(title));
        GridBagConstraints c = new GridBagConstraints();
        c.insets = new Insets(3, 4, 3, 4);
        c.anchor = GridBagConstraints.WEST;
        c.fill = GridBagConstraints.HORIZONTAL;
        int row = 0;
        for (String[] permission : permissions) {
            JSpinner spinner = Spinners.compact(new JSpinner(new SpinnerNumberModel(0, 0, 9999, 1)));
            spinners.put(permission[0], spinner);
            c.gridx = 0;
            c.gridy = row;
            c.weightx = 0;
            panel.add(new JLabel(permission[1]), c);
            c.gridx = 1;
            c.weightx = 1;
            c.fill = GridBagConstraints.NONE;
            panel.add(spinner, c);
            c.fill = GridBagConstraints.HORIZONTAL;
            row++;
        }
        // Keeps the rows at the top of the group instead of centred in whatever height
        // the tab happens to give it.
        c.gridx = 0;
        c.gridy = row;
        c.weighty = 1;
        panel.add(Box.createGlue(), c);
        return panel;
    }
}