/*
 * Copyright (C) 2023 Paul Davis <paul@linuxaudiosystems.com>
 *
 * 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 "canvas/canvas.h"
#include "canvas/container.h"
#include "canvas/debug.h"
#include "canvas/scroll_group.h"
#include "canvas/rectangle.h"

#include "midi_cue_background.h"
#include "midi_cue_editor.h"
#include "midi_view.h"
#include "ui_config.h"
#include "verbose_cursor.h"

using namespace ARDOUR;
using namespace ArdourCanvas;
using namespace Temporal;

MidiCueEditor::MidiCueEditor()
	: vertical_adjustment (0.0, 0.0, 10.0, 400.0)
	, horizontal_adjustment (0.0, 0.0, 1e16)
	, view (nullptr)
{
	build_canvas ();

	_verbose_cursor = new VerboseCursor (*this);
}

MidiCueEditor::~MidiCueEditor ()
{
}

void
MidiCueEditor::build_canvas ()
{
	_canvas_viewport = new ArdourCanvas::GtkCanvasViewport (horizontal_adjustment, vertical_adjustment);

	_canvas = _canvas_viewport->canvas ();
	_canvas->set_background_color (0xff00000a); // UIConfiguration::instance().color ("arrange base"));
	dynamic_cast<ArdourCanvas::GtkCanvas*>(_canvas)->use_nsglview (UIConfiguration::instance().get_nsgl_view_mode () == NSGLHiRes);

	/* scroll group for items that should not automatically scroll
	 *  (e.g verbose cursor). It shares the canvas coordinate space.
	*/
	no_scroll_group = new ArdourCanvas::Container (_canvas->root());

	ArdourCanvas::ScrollGroup* hsg;
	ArdourCanvas::ScrollGroup* hg;
	ArdourCanvas::ScrollGroup* cg;

	h_scroll_group = hg = new ArdourCanvas::ScrollGroup (_canvas->root(), ArdourCanvas::ScrollGroup::ScrollsHorizontally);
	CANVAS_DEBUG_NAME (h_scroll_group, "canvas h scroll");
	_canvas->add_scroller (*hg);

	hv_scroll_group = hsg = new ArdourCanvas::ScrollGroup (_canvas->root(),
							       ArdourCanvas::ScrollGroup::ScrollSensitivity (ArdourCanvas::ScrollGroup::ScrollsVertically|
													     ArdourCanvas::ScrollGroup::ScrollsHorizontally));
	CANVAS_DEBUG_NAME (hv_scroll_group, "canvas hv scroll");
	_canvas->add_scroller (*hsg);

	cursor_scroll_group = cg = new ArdourCanvas::ScrollGroup (_canvas->root(), ArdourCanvas::ScrollGroup::ScrollsHorizontally);
	CANVAS_DEBUG_NAME (cursor_scroll_group, "canvas cursor scroll");
	_canvas->add_scroller (*cg);

	/*a group to hold global rects like punch/loop indicators */
	global_rect_group = new ArdourCanvas::Container (hv_scroll_group);
	CANVAS_DEBUG_NAME (global_rect_group, "global rect group");

        transport_loop_range_rect = new ArdourCanvas::Rectangle (global_rect_group, ArdourCanvas::Rect (0.0, 0.0, 0.0, ArdourCanvas::COORD_MAX));
	CANVAS_DEBUG_NAME (transport_loop_range_rect, "loop rect");
	transport_loop_range_rect->hide();

	/*a group to hold time (measure) lines */
	time_line_group = new ArdourCanvas::Container (h_scroll_group);
	CANVAS_DEBUG_NAME (time_line_group, "time line group");

	_trackview_group = new ArdourCanvas::Container (hv_scroll_group);
	CANVAS_DEBUG_NAME (_trackview_group, "Canvas TrackViews");

	// used as rubberband rect
	rubberband_rect = new ArdourCanvas::Rectangle (hv_scroll_group, ArdourCanvas::Rect (0.0, 0.0, 0.0, 0.0));
	rubberband_rect->hide();

	bg = new CueMidiBackground (hv_scroll_group);
	_canvas_viewport->signal_size_allocate().connect (sigc::mem_fun(*this, &MidiCueEditor::canvas_allocate));
}

void
MidiCueEditor::canvas_allocate (Gtk::Allocation alloc)
{
	bg->set_size (alloc.get_width(), alloc.get_height());
}

timepos_t
MidiCueEditor::snap_to_grid (timepos_t const & presnap, Temporal::RoundMode direction, SnapPref gpref) const
{
	/* BBT time only */
	return snap_to_bbt (presnap, direction, gpref);
}

void
MidiCueEditor::snap_to_internal (timepos_t& start, Temporal::RoundMode direction, SnapPref pref, bool ensure_snap) const
{
	UIConfiguration const& uic (UIConfiguration::instance ());
	const timepos_t presnap = start;


	timepos_t dist = timepos_t::max (start.time_domain()); // this records the distance of the best snap result we've found so far
	timepos_t best = timepos_t::max (start.time_domain()); // this records the best snap-result we've found so far

	timepos_t pre (presnap);
	timepos_t post (snap_to_grid (pre, direction, pref));

	check_best_snap (presnap, post, dist, best);

	if (timepos_t::max (start.time_domain()) == best) {
		return;
	}

	/* now check "magnetic" state: is the grid within reasonable on-screen distance to trigger a snap?
	 * this also helps to avoid snapping to somewhere the user can't see.  (i.e.: I clicked on a region and it disappeared!!)
	 * ToDo: Perhaps this should only occur if EditPointMouse?
	 */
	samplecnt_t snap_threshold_s = pixel_to_sample (uic.get_snap_threshold ());

	if (!ensure_snap && ::llabs (best.distance (presnap).samples()) > snap_threshold_s) {
		return;
	}

	start = best;
}

samplecnt_t
MidiCueEditor::current_page_samples() const
{
	return (samplecnt_t) _visible_canvas_width* samples_per_pixel;
}

void
MidiCueEditor::apply_midi_note_edit_op (ARDOUR::MidiOperator& op, const RegionSelection& rs)
{
}

PBD::Command*
MidiCueEditor::apply_midi_note_edit_op_to_region (ARDOUR::MidiOperator& op, MidiRegionView& mrv)
{
#if 0
	Evoral::Sequence<Temporal::Beats>::Notes selected;
	mrv.selection_as_notelist (selected, true);

	if (selected.empty()) {
		return 0;
	}

	vector<Evoral::Sequence<Temporal::Beats>::Notes> v;
	v.push_back (selected);

	timepos_t pos = mrv.midi_region()->source_position();

	return op (mrv.midi_region()->model(), pos.beats(), v);
#endif

	return nullptr;
}

bool
MidiCueEditor::canvas_note_event (GdkEvent* event, ArdourCanvas::Item*)
{
	return false;
}

Gtk::Widget&
MidiCueEditor::viewport()
{
	return *_canvas_viewport;
}

void
MidiCueEditor::set_region (std::shared_ptr<ARDOUR::MidiTrack> t, std::shared_ptr<ARDOUR::MidiRegion> r)
{
	delete view;
	view = nullptr;

	if (!t || !r) {
		return;
	}

	view = new MidiView (t, *hv_scroll_group, *this, *bg, 0xff0000ff);
	view->set_region (r);

	bg->set_view (view);
}