/* vim:set et sts=4 sw=4:

 *

 * ibus - The Input Bus

 *

 * Copyright(c) 2011-2015 Peng Huang <shawn.p.huang@gmail.com>

 * Copyright(c) 2015-2017 Takao Fujiwara <takao.fujiwara1@gmail.com>

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301

 * USA

 */

class CandidateArea : Gtk.Box {

    private bool m_vertical;

    private Gtk.Label[] m_labels;

    private Gtk.Label[] m_candidates;

    private Gtk.Widget[] m_widgets;

    private IBus.Text[] m_ibus_candidates;

    private uint m_focus_candidate;

    private bool m_show_cursor;

    private ThemedRGBA m_rgba;

    private const string LABELS[] = {

        "1.", "2.", "3.", "4.", "5.", "6.", "7.", "8.",

        "9.", "0.", "a.", "b.", "c.", "d.", "e.", "f."

    };

    private const string PREV_PAGE_ICONS[] = {

        "go-previous",

        "go-up"

    };

    private const string NEXT_PAGE_ICONS[] = {

        "go-next",

        "go-down"

    };

    public signal void candidate_clicked(uint index, uint button, uint state);

    public signal void page_up();

    public signal void page_down();

    public signal void cursor_up();

    public signal void cursor_down();

    public CandidateArea(bool vertical) {

        GLib.Object();

        set_vertical(vertical, true);

        m_rgba = new ThemedRGBA(this);

    }

    public bool candidate_scrolled(Gdk.EventScroll event) {

        switch (event.direction) {

        case Gdk.ScrollDirection.UP:

            cursor_up();

            break;

        case Gdk.ScrollDirection.DOWN:

            cursor_down();

            break;

        }

        return true;

    }

    public bool get_vertical() {

        return m_vertical;

    }

    public void set_vertical(bool vertical, bool force = false) {

        if (!force && m_vertical == vertical)

            return;

        m_vertical = vertical;

        orientation = vertical ?

            Gtk.Orientation.VERTICAL :

            Gtk.Orientation.HORIZONTAL;

        recreate_ui();

        if (m_ibus_candidates.length > 0) {

            // Workaround a vala issue

            // https://bugzilla.gnome.org/show_bug.cgi?id=661130

            set_candidates((owned)m_ibus_candidates,

                           m_focus_candidate,

                           m_show_cursor);

            show_all();

        }

    }

    public void set_labels(IBus.Text[] labels) {

        int i;

        for (i = 0; i < int.min(16, labels.length); i++)

            m_labels[i].set_text(labels[i].get_text());

        for (; i < 16; i++)

            m_labels[i].set_text(LABELS[i]);

    }

    public void set_candidates(IBus.Text[] candidates,

                               uint focus_candidate = 0,

                               bool show_cursor = true) {

        m_ibus_candidates = candidates;

        m_focus_candidate = focus_candidate;

        m_show_cursor = show_cursor;

        assert(candidates.length <= 16);

        for (int i = 0 ; i < 16 ; i++) {

            Gtk.Label label = m_candidates[i];

            bool visible = false;

            if (i < candidates.length) {

                Pango.AttrList attrs = get_pango_attr_list_from_ibus_text(candidates[i]);

                if (i == focus_candidate && show_cursor) {

                    Pango.Attribute pango_attr = Pango.attr_foreground_new(

                            (uint16)(m_rgba.selected_fg.red * uint16.MAX),

                            (uint16)(m_rgba.selected_fg.green * uint16.MAX),

                            (uint16)(m_rgba.selected_fg.blue * uint16.MAX));

                    pango_attr.start_index = 0;

                    pango_attr.end_index = candidates[i].get_text().length;

                    attrs.insert((owned)pango_attr);

                    pango_attr = Pango.attr_background_new(

                           (uint16)(m_rgba.selected_bg.red * uint16.MAX),

                           (uint16)(m_rgba.selected_bg.green * uint16.MAX),

                           (uint16)(m_rgba.selected_bg.blue * uint16.MAX));

                    pango_attr.start_index = 0;

                    pango_attr.end_index = candidates[i].get_text().length;

                    attrs.insert((owned)pango_attr);

                }

                label.set_text(candidates[i].get_text());

                label.set_attributes(attrs);

                visible = true;

            } else {

                label.set_text("");

                label.set_attributes(new Pango.AttrList());

            }

            if (m_vertical) {

                m_widgets[i * 2].set_visible(visible);

                m_widgets[i * 2 +1].set_visible(visible);

            } else {

                m_widgets[i].set_visible(visible);

            }

        }

    }

    private void recreate_ui() {

        foreach (Gtk.Widget w in get_children()) {

            w.destroy();

        }

        Gtk.Button prev_button = new Gtk.Button();

        prev_button.clicked.connect((b) => page_up());

        prev_button.set_image(new Gtk.Image.from_icon_name(

                                  PREV_PAGE_ICONS[orientation],

                                  Gtk.IconSize.MENU));

        prev_button.set_relief(Gtk.ReliefStyle.NONE);

        Gtk.Button next_button = new Gtk.Button();

        next_button.clicked.connect((b) => page_down());

        next_button.set_image(new Gtk.Image.from_icon_name(

                                  NEXT_PAGE_ICONS[orientation],

                                  Gtk.IconSize.MENU));

        next_button.set_relief(Gtk.ReliefStyle.NONE);

        if (m_vertical) {

            Gtk.EventBox container_ebox = new Gtk.EventBox();

            container_ebox.add_events(Gdk.EventMask.SCROLL_MASK);

            container_ebox.scroll_event.connect(candidate_scrolled);

            add(container_ebox);

            Gtk.Box vbox = new Gtk.Box(Gtk.Orientation.VERTICAL, 0);

            container_ebox.add(vbox);

            // Add Candidates

            Gtk.Box candidates_hbox = new Gtk.Box(Gtk.Orientation.HORIZONTAL, 0);

            vbox.pack_start(candidates_hbox, false, false, 0);

            Gtk.Box labels_vbox = new Gtk.Box(Gtk.Orientation.VERTICAL, 0);

            labels_vbox.set_homogeneous(true);

            Gtk.Box candidates_vbox = new Gtk.Box(Gtk.Orientation.VERTICAL, 0);

            candidates_vbox.set_homogeneous(true);

            candidates_hbox.pack_start(labels_vbox, false, false, 4);

            candidates_hbox.pack_start(new VSeparator(), false, false, 0);

            candidates_hbox.pack_start(candidates_vbox, true, true, 4);

            // Add HSeparator

            vbox.pack_start(new HSeparator(), false, false, 0);

            // Add buttons

            Gtk.Box buttons_hbox = new Gtk.Box(Gtk.Orientation.HORIZONTAL, 0);

            Gtk.Label state_label = new Gtk.Label(null);

            state_label.set_size_request(20, -1);

            buttons_hbox.pack_start(state_label, true, true, 0);

            buttons_hbox.pack_start(prev_button, false, false, 0);

            buttons_hbox.pack_start(next_button, false, false, 0);

            vbox.pack_start(buttons_hbox, false, false, 0);

            m_labels = {};

            m_candidates = {};

            m_widgets = {};

            for (int i = 0; i < 16; i++) {

                Gtk.Label label = new Gtk.Label(LABELS[i]);

                label.set_halign(Gtk.Align.START);

                label.set_valign(Gtk.Align.CENTER);

                label.show();

                m_labels += label;

                Gtk.Label candidate = new Gtk.Label("test");

                candidate.set_halign(Gtk.Align.START);

                candidate.set_valign(Gtk.Align.CENTER);

                candidate.show();

                m_candidates += candidate;

                /* Use Gtk.Widget.set_margin_start() since gtk 3.12 */

                label.set_padding(8, 0);

                candidate.set_padding(8, 0);

                // Make a copy of i to workaround a bug in vala.

                // https://bugzilla.gnome.org/show_bug.cgi?id=628336

                int index = i;

                Gtk.EventBox label_ebox = new Gtk.EventBox();

                label_ebox.set_no_show_all(true);

                label_ebox.button_press_event.connect((w, e) => {

                    candidate_clicked(i, e.button, e.state);

                    return true;

                });

                label_ebox.add(label);

                labels_vbox.pack_start(label_ebox, false, false, 2);

                m_widgets += label_ebox;

                Gtk.EventBox candidate_ebox = new Gtk.EventBox();

                candidate_ebox.set_no_show_all(true);

                candidate_ebox.button_press_event.connect((w, e) => {

                    candidate_clicked(index, e.button, e.state);

                    return true;

                });

                candidate_ebox.add(candidate);

                candidates_vbox.pack_start(candidate_ebox, false, false, 2);

                m_widgets += candidate_ebox;

            }

        } else {

            Gtk.EventBox container_ebox = new Gtk.EventBox();

            container_ebox.add_events(Gdk.EventMask.SCROLL_MASK);

            container_ebox.scroll_event.connect(candidate_scrolled);

            add(container_ebox);

            Gtk.Box hbox = new Gtk.Box(Gtk.Orientation.HORIZONTAL, 0);

            container_ebox.add(hbox);

            m_labels = {};

            m_candidates = {};

            m_widgets = {};

            for (int i = 0; i < 16; i++) {

                Gtk.Label label = new Gtk.Label(LABELS[i]);

                label.set_halign(Gtk.Align.START);

                label.set_valign(Gtk.Align.CENTER);

                label.show();

                m_labels += label;

                Gtk.Label candidate = new Gtk.Label("test");

                candidate.set_halign(Gtk.Align.START);

                candidate.set_valign(Gtk.Align.CENTER);

                candidate.show();

                m_candidates += candidate;

                Gtk.Box candidate_hbox = new Gtk.Box(Gtk.Orientation.HORIZONTAL, 0);

                candidate_hbox.show();

                candidate_hbox.pack_start(label, false, false, 2);

                candidate_hbox.pack_start(candidate, false, false, 2);

                // Make a copy of i to workaround a bug in vala.

                // https://bugzilla.gnome.org/show_bug.cgi?id=628336

                int index = i;

                Gtk.EventBox ebox = new Gtk.EventBox();

                ebox.set_no_show_all(true);

                ebox.button_press_event.connect((w, e) => {

                    candidate_clicked(index, e.button, e.state);

                    return true;

                });

                ebox.add(candidate_hbox);

                hbox.pack_start(ebox, false, false, 4);

                m_widgets += ebox;

            }

            hbox.pack_start(new VSeparator(), false, false, 0);

            hbox.pack_start(prev_button, false, false, 0);

            hbox.pack_start(next_button, false, false, 0);

        }

    }

}