/*
 * Copyright (C) 2008-2014 David Robillard <d@drobilla.net>
 * Copyright (C) 2009-2011 Carl Hetherington <carl@carlh.net>
 * Copyright (C) 2009-2013 Paul Davis <paul@linuxaudiosystems.com>
 * Copyright (C) 2014-2017 Robin Gareus <robin@gareus.org>
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

#include "ardour/midi_track.h"
#include "evoral/midi_events.h"
#include <iostream>

#include "gtkmm2ext/keyboard.h"

#include "editing.h"
#include "midi_streamview.h"
#include "midi_time_axis.h"
#include "piano_roll_header.h"
#include "public_editor.h"
#include "ui_config.h"

using namespace std;
using namespace Gtkmm2ext;

PianoRollHeader::Color PianoRollHeader::white             = PianoRollHeader::Color (0.77f, 0.78f, 0.76f);
PianoRollHeader::Color PianoRollHeader::white_highlight   = PianoRollHeader::Color (1.00f, 0.40f, 0.40f);
PianoRollHeader::Color PianoRollHeader::white_shade_light = PianoRollHeader::Color (0.95f, 0.95f, 0.95f);
PianoRollHeader::Color PianoRollHeader::white_shade_dark  = PianoRollHeader::Color (0.56f, 0.56f, 0.56f);

PianoRollHeader::Color PianoRollHeader::black             = PianoRollHeader::Color (0.24f, 0.24f, 0.24f);
PianoRollHeader::Color PianoRollHeader::black_highlight   = PianoRollHeader::Color (0.60f, 0.10f, 0.10f);
PianoRollHeader::Color PianoRollHeader::black_shade_light = PianoRollHeader::Color (0.46f, 0.46f, 0.46f);
PianoRollHeader::Color PianoRollHeader::black_shade_dark  = PianoRollHeader::Color (0.1f, 0.1f, 0.1f);

PianoRollHeader::Color::Color ()
	: r (1.0f)
	, g (1.0f)
	, b (1.0f)
{
}

PianoRollHeader::Color::Color (double _r, double _g, double _b)
	: r (_r)
	, g (_g)
	, b (_b)
{
}

inline void
PianoRollHeader::Color::set (const PianoRollHeader::Color& c)
{
	r = c.r;
	g = c.g;
	b = c.b;
}

PianoRollHeader::PianoRollHeader (MidiStreamView& v)
	: _view (v)
	, _highlighted_note (NO_MIDI_NOTE)
	, _clicked_note (NO_MIDI_NOTE)
	, _dragging (false)
{
	add_events (Gdk::BUTTON_PRESS_MASK |
	            Gdk::BUTTON_RELEASE_MASK |
	            Gdk::POINTER_MOTION_MASK |
	            Gdk::ENTER_NOTIFY_MASK |
	            Gdk::LEAVE_NOTIFY_MASK |
	            Gdk::SCROLL_MASK);

	for (int i = 0; i < 128; ++i) {
		_active_notes[i] = false;
	}

	_view.NoteRangeChanged.connect (sigc::mem_fun (*this, &PianoRollHeader::note_range_changed));
}

inline void
create_path (Cairo::RefPtr<Cairo::Context> cr, double x[], double y[], int start, int stop)
{
	cr->move_to (x[start], y[start]);

	for (int i = start + 1; i <= stop; ++i) {
		cr->line_to (x[i], y[i]);
	}
}

inline void
render_rect (Cairo::RefPtr<Cairo::Context> cr, int /*note*/, double x[], double y[],
             PianoRollHeader::Color& bg, PianoRollHeader::Color& tl_shadow, PianoRollHeader::Color& br_shadow)
{
	cr->set_source_rgb (bg.r, bg.g, bg.b);
	create_path (cr, x, y, 0, 4);
	cr->fill ();

	cr->set_source_rgb (tl_shadow.r, tl_shadow.g, tl_shadow.b);
	create_path (cr, x, y, 0, 2);
	cr->stroke ();

	cr->set_source_rgb (br_shadow.r, br_shadow.g, br_shadow.b);
	create_path (cr, x, y, 2, 4);
	cr->stroke ();
}

inline void
render_cf (Cairo::RefPtr<Cairo::Context> cr, int /*note*/, double x[], double y[],
           PianoRollHeader::Color& bg, PianoRollHeader::Color& tl_shadow, PianoRollHeader::Color& br_shadow)
{
	cr->set_source_rgb (bg.r, bg.g, bg.b);
	create_path (cr, x, y, 0, 6);
	cr->fill ();

	cr->set_source_rgb (tl_shadow.r, tl_shadow.g, tl_shadow.b);
	create_path (cr, x, y, 0, 4);
	cr->stroke ();

	cr->set_source_rgb (br_shadow.r, br_shadow.g, br_shadow.b);
	create_path (cr, x, y, 4, 6);
	cr->stroke ();
}

inline void
render_eb (Cairo::RefPtr<Cairo::Context> cr, int /*note*/, double x[], double y[],
           PianoRollHeader::Color& bg, PianoRollHeader::Color& tl_shadow, PianoRollHeader::Color& br_shadow)
{
	cr->set_source_rgb (bg.r, bg.g, bg.b);
	create_path (cr, x, y, 0, 6);
	cr->fill ();

	cr->set_source_rgb (tl_shadow.r, tl_shadow.g, tl_shadow.b);
	create_path (cr, x, y, 0, 2);
	cr->stroke ();
	create_path (cr, x, y, 4, 5);
	cr->stroke ();

	cr->set_source_rgb (br_shadow.r, br_shadow.g, br_shadow.b);
	create_path (cr, x, y, 2, 4);
	cr->stroke ();
	create_path (cr, x, y, 5, 6);
	cr->stroke ();
}

inline void
render_dga (Cairo::RefPtr<Cairo::Context> cr, int /*note*/, double x[], double y[],
            PianoRollHeader::Color& bg, PianoRollHeader::Color& tl_shadow, PianoRollHeader::Color& br_shadow)
{
	cr->set_source_rgb (bg.r, bg.g, bg.b);
	create_path (cr, x, y, 0, 8);
	cr->fill ();

	cr->set_source_rgb (tl_shadow.r, tl_shadow.g, tl_shadow.b);
	create_path (cr, x, y, 0, 4);
	cr->stroke ();
	create_path (cr, x, y, 6, 7);
	cr->stroke ();

	cr->set_source_rgb (br_shadow.r, br_shadow.g, br_shadow.b);
	create_path (cr, x, y, 4, 6);
	cr->stroke ();
	create_path (cr, x, y, 7, 8);
	cr->stroke ();
}

void
PianoRollHeader::get_path (PianoRollHeader::ItemType note_type, int note, double x[], double y[])
{
	double y_pos = floor (_view.note_to_y (note)) + 1.5f;
	double note_height;
	double other_y1 = floor (_view.note_to_y (note + 1)) + floor (_note_height / 2.0f) + 2.5f;
	double other_y2 = floor (_view.note_to_y (note - 1)) + floor (_note_height / 2.0f) + 1.0f;
	double width    = get_width ();

	if (note == 0) {
		note_height = floor (_view.contents_height ()) - y_pos + 2.;
	} else {
		note_height = floor (_view.note_to_y (note - 1)) - y_pos + 2.;
	}

	switch (note_type) {
		case BLACK_SEPARATOR:
			x[0] = 1.5f;
			y[0] = y_pos;
			x[1] = _black_note_width;
			y[1] = y_pos;
			break;
		case BLACK_MIDDLE_SEPARATOR:
			x[0] = _black_note_width;
			y[0] = y_pos + floor (_note_height / 2.0f);
			x[1] = width - 1.0f;
			y[1] = y[0];
			break;
		case BLACK:
			x[0] = 1.5f;
			y[0] = y_pos + note_height - 0.5f;
			x[1] = 1.5f;
			y[1] = y_pos + 1.0f;
			x[2] = _black_note_width;
			y[2] = y_pos + 1.0f;
			x[3] = _black_note_width;
			y[3] = y_pos + note_height - 0.5f;
			x[4] = 1.5f;
			y[4] = y_pos + note_height - 0.5f;
			return;
		case WHITE_SEPARATOR:
			x[0] = 1.5f;
			y[0] = y_pos;
			x[1] = width - 1.5f;
			y[1] = y_pos;
			break;
		case WHITE_RECT:
			x[0] = 1.5f;
			y[0] = y_pos + note_height - 0.5f;
			x[1] = 1.5f;
			y[1] = y_pos + 1.0f;
			x[2] = width - 1.5f;
			y[2] = y_pos + 1.0f;
			x[3] = width - 1.5f;
			y[3] = y_pos + note_height - 0.5f;
			x[4] = 1.5f;
			y[4] = y_pos + note_height - 0.5f;
			return;
		case WHITE_CF:
			x[0] = 1.5f;
			y[0] = y_pos + note_height - 1.5f;
			x[1] = 1.5f;
			y[1] = y_pos + 1.0f;
			x[2] = _black_note_width + 1.0f;
			y[2] = y_pos + 1.0f;
			x[3] = _black_note_width + 1.0f;
			y[3] = other_y1;
			x[4] = width - 1.5f;
			y[4] = other_y1;
			x[5] = width - 1.5f;
			y[5] = y_pos + note_height - 1.5f;
			x[6] = 1.5f;
			y[6] = y_pos + note_height - 1.5f;
			return;
		case WHITE_EB:
			x[0] = 1.5f;
			y[0] = y_pos + note_height - 1.5f;
			x[1] = 1.5f;
			y[1] = y_pos + 1.0f;
			x[2] = width - 1.5f;
			y[2] = y_pos + 1.0f;
			x[3] = width - 1.5f;
			y[3] = other_y2;
			x[4] = _black_note_width + 1.0f;
			y[4] = other_y2;
			x[5] = _black_note_width + 1.0f;
			y[5] = y_pos + note_height - 1.5f;
			x[6] = 1.5f;
			y[6] = y_pos + note_height - 1.5f;
			return;
		case WHITE_DGA:
			x[0] = 1.5f;
			y[0] = y_pos + note_height - 1.5f;
			x[1] = 1.5f;
			y[1] = y_pos + 1.0f;
			x[2] = _black_note_width + 1.0f;
			y[2] = y_pos + 1.0f;
			x[3] = _black_note_width + 1.0f;
			y[3] = other_y1;
			x[4] = width - 1.5f;
			y[4] = other_y1;
			x[5] = width - 1.5f;
			y[5] = other_y2;
			x[6] = _black_note_width + 1.0f;
			y[6] = other_y2;
			x[7] = _black_note_width + 1.0f;
			y[7] = y_pos + note_height - 1.5f;
			x[8] = 1.5f;
			y[8] = y_pos + note_height - 1.5f;
			return;
		default:
			return;
	}
}

bool
PianoRollHeader::on_expose_event (GdkEventExpose* ev)
{
	GdkRectangle& rect = ev->area;
	double        font_size;
	int           lowest, highest;
	double        x[9];
	double        y[9];
	Color         bg, tl_shadow, br_shadow;
	int           oct_rel;

	int y1 = max (rect.y, 0);
	int y2 = min (rect.y + rect.height, (int)floor (_view.contents_height () - 1.0f));

	Cairo::RefPtr<Cairo::Context>        cr  = get_window ()->create_cairo_context ();
	Cairo::RefPtr<Cairo::LinearGradient> pat = Cairo::LinearGradient::create (0, 0, _black_note_width, 0);

	//Cairo::TextExtents te;
	lowest  = max (_view.lowest_note (), _view.y_to_note (y2));
	highest = min (_view.highest_note (), _view.y_to_note (y1));

	if (lowest > 127) {
		lowest = 0;
	}

	cr->select_font_face ("Georgia", Cairo::FONT_SLANT_NORMAL, Cairo::FONT_WEIGHT_BOLD);
	font_size = min ((double)10.0f, _note_height - 4.0f);
	cr->set_font_size (font_size);

	/* fill the entire rect with the color for non-highlighted white notes.
	 * then we won't have to draw the background for those notes,
	 * and would only have to draw the background for the one highlighted white note*/
	//cr->rectangle(rect.x, rect.y, rect.width, rect.height);
	//cr->set_source_rgb(white.r, white.g, white.b);
	//cr->fill();

	cr->set_line_width (1.0f);

	/* draw vertical lines with shade at both ends of the widget */
	cr->set_source_rgb (0.0f, 0.0f, 0.0f);
	cr->move_to (0.5f, rect.y);
	cr->line_to (0.5f, rect.y + rect.height);
	cr->stroke ();
	cr->move_to (get_width () - 0.5f, rect.y);
	cr->line_to (get_width () - 0.5f, rect.y + rect.height);
	cr->stroke ();

	//pat->add_color_stop_rgb(0.0, 0.33, 0.33, 0.33);
	//pat->add_color_stop_rgb(0.2, 0.39, 0.39, 0.39);
	//pat->add_color_stop_rgb(1.0, 0.22, 0.22, 0.22);
	//cr->set_source(pat);

	for (int i = lowest; i <= highest; ++i) {
		oct_rel = i % 12;

		switch (oct_rel) {
			case 1:
			case 3:
			case 6:
			case 8:
			case 10:
				/* black note */
				if (i == _highlighted_note) {
					bg.set (black_highlight);
				} else {
					bg.set (black);
				}

				if (_active_notes[i]) {
					tl_shadow.set (black_shade_dark);
					br_shadow.set (black_shade_light);
				} else {
					tl_shadow.set (black_shade_light);
					br_shadow.set (black_shade_dark);
				}

				/* draw black separators */
				cr->set_source_rgb (0.0f, 0.0f, 0.0f);
				get_path (BLACK_SEPARATOR, i, x, y);
				create_path (cr, x, y, 0, 1);
				cr->stroke ();

				get_path (BLACK_MIDDLE_SEPARATOR, i, x, y);
				create_path (cr, x, y, 0, 1);
				cr->stroke ();

				get_path (BLACK, i, x, y);
				render_rect (cr, i, x, y, bg, tl_shadow, br_shadow);
				break;

			default:
				/* white note */
				if (i == _highlighted_note) {
					bg.set (white_highlight);
				} else {
					bg.set (white);
				}

				if (_active_notes[i]) {
					tl_shadow.set (white_shade_dark);
					br_shadow.set (white_shade_light);
				} else {
					tl_shadow.set (white_shade_light);
					br_shadow.set (white_shade_dark);
				}

				switch (oct_rel) {
					case 0:
					case 5:
						if (i == _view.highest_note ()) {
							get_path (WHITE_RECT, i, x, y);
							render_rect (cr, i, x, y, bg, tl_shadow, br_shadow);
						} else {
							get_path (WHITE_CF, i, x, y);
							render_cf (cr, i, x, y, bg, tl_shadow, br_shadow);
						}
						break;

					case 2:
					case 7:
					case 9:
						if (i == _view.highest_note ()) {
							get_path (WHITE_EB, i, x, y);
							render_eb (cr, i, x, y, bg, tl_shadow, br_shadow);
						} else if (i == _view.lowest_note ()) {
							get_path (WHITE_CF, i, x, y);
							render_cf (cr, i, x, y, bg, tl_shadow, br_shadow);
						} else {
							get_path (WHITE_DGA, i, x, y);
							render_dga (cr, i, x, y, bg, tl_shadow, br_shadow);
						}
						break;

					case 4:
					case 11:
						cr->set_source_rgb (0.0f, 0.0f, 0.0f);
						get_path (WHITE_SEPARATOR, i, x, y);
						create_path (cr, x, y, 0, 1);
						cr->stroke ();

						if (i == _view.lowest_note ()) {
							get_path (WHITE_RECT, i, x, y);
							render_rect (cr, i, x, y, bg, tl_shadow, br_shadow);
						} else {
							get_path (WHITE_EB, i, x, y);
							render_eb (cr, i, x, y, bg, tl_shadow, br_shadow);
						}
						break;

					default:
						break;
				}
				break;
		}

		/* render the name of which C this is */
		if (oct_rel == 0) {
			std::stringstream s;
			double            y           = floor (_view.note_to_y (i)) - 0.5f;
			double            note_height = floor (_view.note_to_y (i - 1)) - y;

			int cn = i / 12 - 1;
			s << "C" << cn;

			//cr->get_text_extents(s.str(), te);
			cr->set_source_rgb (0.30f, 0.30f, 0.30f);
			cr->move_to (2.0f, y + note_height - 1.0f - (note_height - font_size) / 2.0f);
			cr->show_text (s.str ());
		}
	}

	return true;
}

bool
PianoRollHeader::on_motion_notify_event (GdkEventMotion* ev)
{
	int note = _view.y_to_note (ev->y);
	set_note_highlight (note);

	if (_dragging) {
		if (false /*editor().current_mouse_mode() == Editing::MouseRange*/) { //ToDo:  fix this.  this mode is buggy, and of questionable utility anyway

			/* select note range */

			if (Keyboard::no_modifiers_active (ev->state)) {
				AddNoteSelection (note); // EMIT SIGNAL
			}

		} else {
			/* play notes */
			/* redraw already taken care of above in set_note_highlight */
			if (_clicked_note != NO_MIDI_NOTE && _clicked_note != note) {
				_active_notes[_clicked_note] = false;
				send_note_off (_clicked_note);

				_clicked_note = note;

				if (!_active_notes[note]) {
					_active_notes[note] = true;
					send_note_on (note);
				}
			}
		}
	}

	//win->process_updates(false);

	return true;
}

bool
PianoRollHeader::on_button_press_event (GdkEventButton* ev)
{
	int  note     = _view.y_to_note (ev->y);
	bool tertiary = Keyboard::modifier_state_contains (ev->state, Keyboard::TertiaryModifier);

	if (ev->button == 2 && Keyboard::no_modifiers_active (ev->state)) {
		SetNoteSelection (note); // EMIT SIGNAL
		return true;
	} else if (tertiary && (ev->button == 1 || ev->button == 2)) {
		ExtendNoteSelection (note); // EMIT SIGNAL
		return true;
	} else if (ev->button == 1 && note >= 0 && note < 128) {
		add_modal_grab ();
		_dragging = true;

		if (!_active_notes[note]) {
			_active_notes[note] = true;
			_clicked_note       = note;
			send_note_on (note);

			invalidate_note_range (note, note);
		} else {
			reset_clicked_note (note);
		}
	}

	return true;
}

bool
PianoRollHeader::on_button_release_event (GdkEventButton* ev)
{
	int note = _view.y_to_note (ev->y);

	if (false /*editor().current_mouse_mode() == Editing::MouseRange*/) { //Todo:  this mode is buggy, and of questionable utility anyway

		if (Keyboard::no_modifiers_active (ev->state)) {
			AddNoteSelection (note); // EMIT SIGNAL
		} else if (Keyboard::modifier_state_equals (ev->state, Keyboard::PrimaryModifier)) {
			ToggleNoteSelection (note); // EMIT SIGNAL
		} else if (Keyboard::modifier_state_equals (ev->state, Keyboard::RangeSelectModifier)) {
			ExtendNoteSelection (note); // EMIT SIGNAL
		}

	} else {
		if (_dragging) {
			remove_modal_grab ();

			if (note == _clicked_note) {
				reset_clicked_note (note);
			}
		}
	}

	_dragging = false;
	return true;
}

void
PianoRollHeader::set_note_highlight (uint8_t note)
{
	if (_highlighted_note == note) {
		return;
	}

	if (_highlighted_note != NO_MIDI_NOTE) {
		if (note > _highlighted_note) {
			invalidate_note_range (_highlighted_note, note);
		} else {
			invalidate_note_range (note, _highlighted_note);
		}
	}

	_highlighted_note = note;

	if (_highlighted_note != NO_MIDI_NOTE) {
		invalidate_note_range (_highlighted_note, _highlighted_note);
	}
}

bool
PianoRollHeader::on_enter_notify_event (GdkEventCrossing* ev)
{
	set_note_highlight (_view.y_to_note (ev->y));
	return true;
}

bool
PianoRollHeader::on_leave_notify_event (GdkEventCrossing*)
{
	if (has_grab () && _dragging) {
		return true;
	}
	invalidate_note_range (_highlighted_note, _highlighted_note);

	if (_clicked_note != NO_MIDI_NOTE) {
		reset_clicked_note (_clicked_note, _clicked_note != _highlighted_note);
	}

	_highlighted_note = NO_MIDI_NOTE;
	return true;
}

bool
PianoRollHeader::on_scroll_event (GdkEventScroll*)
{
	return true;
}

void
PianoRollHeader::note_range_changed ()
{
	_note_height = floor (_view.note_height ()) + 0.5f;
	queue_draw ();
}

void
PianoRollHeader::invalidate_note_range (int lowest, int highest)
{
	Glib::RefPtr<Gdk::Window> win = get_window ();
	Gdk::Rectangle            rect;

	/* the non-rectangular geometry of some of the notes requires more
	 * redraws than the notes that actually changed.
	 */
	switch (lowest % 12) {
		case 0:
		case 5:
			lowest = max ((int)_view.lowest_note (), lowest);
			break;
		default:
			lowest = max ((int)_view.lowest_note (), lowest - 1);
			break;
	}

	switch (highest % 12) {
		case 4:
		case 11:
			highest = min ((int)_view.highest_note (), highest);
			break;
		case 1:
		case 3:
		case 6:
		case 8:
		case 10:
			highest = min ((int)_view.highest_note (), highest + 1);
			break;
		default:
			highest = min ((int)_view.highest_note (), highest + 2);
			break;
	}

	double y      = _view.note_to_y (highest);
	double height = _view.note_to_y (lowest - 1) - y;

	rect.set_x (0);
	rect.set_width (get_width ());
	rect.set_y ((int)floor (y));
	rect.set_height ((int)floor (height));

	if (win) {
		win->invalidate_rect (rect, false);
	}
}

void
PianoRollHeader::on_size_request (Gtk::Requisition* r)
{
	r->width = std::max (20.f, rintf (20.f * UIConfiguration::instance ().get_ui_scale ()));
}

void
PianoRollHeader::on_size_allocate (Gtk::Allocation& a)
{
	DrawingArea::on_size_allocate (a);

	_black_note_width = floor (0.7 * get_width ()) + 0.5f;
}

void
PianoRollHeader::send_note_on (uint8_t note)
{
	boost::shared_ptr<ARDOUR::MidiTrack> track = _view.trackview ().midi_track ();
	MidiTimeAxisView*                    mtv   = dynamic_cast<MidiTimeAxisView*> (&_view.trackview ());

	//cerr << "note on: " << (int) note << endl;

	if (track) {
		_event[0] = (MIDI_CMD_NOTE_ON | mtv->get_preferred_midi_channel ());
		_event[1] = note;
		_event[2] = 100;

		track->write_immediate_event (Evoral::MIDI_EVENT, 3, _event);
	}
}

void
PianoRollHeader::send_note_off (uint8_t note)
{
	boost::shared_ptr<ARDOUR::MidiTrack> track = _view.trackview ().midi_track ();
	MidiTimeAxisView*                    mtv   = dynamic_cast<MidiTimeAxisView*> (&_view.trackview ());

	if (track) {
		_event[0] = (MIDI_CMD_NOTE_OFF | mtv->get_preferred_midi_channel ());
		_event[1] = note;
		_event[2] = 100;

		track->write_immediate_event (Evoral::MIDI_EVENT, 3, _event);
	}
}

void
PianoRollHeader::reset_clicked_note (uint8_t note, bool invalidate)
{
	_active_notes[note] = false;
	_clicked_note       = NO_MIDI_NOTE;
	send_note_off (note);
	if (invalidate) {
		invalidate_note_range (note, note);
	}
}

PublicEditor&
PianoRollHeader::editor () const
{
	return _view.trackview ().editor ();
}