#include "labelslider.h"

#include "project/undo.h"
#include "panels/viewer.h"
#include "io/config.h"
#include "debug.h"

#include <QMouseEvent>
#include <QInputDialog>
#include <QApplication>

LabelSlider::LabelSlider(QWidget* parent) : QLabel(parent) {
    // set a default frame rate - fallback, shouldn't ever really be used
	frame_rate = 30;

	decimal_places = 1;
	drag_start = false;
	drag_proc = false;
	min_enabled = false;
	max_enabled = false;
	set_color();
    set_default_cursor();
	internal_value = -1;
	set = false;
	display_type = LABELSLIDER_NORMAL;

	set_default_value(0);
}

void LabelSlider::set_frame_rate(double d) {
	frame_rate = d;
}

void LabelSlider::set_display_type(int type) {
	display_type = type;
	setText(valueToString(internal_value));
}

void LabelSlider::set_value(double v, bool userSet) {
	set = true;
	if (v != internal_value) {
		if (min_enabled && v < min_value) {
			internal_value = min_value;
		} else if (max_enabled && v > max_value) {
			internal_value = max_value;
		} else {
			internal_value = v;
		}

		setText(valueToString(internal_value));
		if (userSet) emit valueChanged();
	}
}

bool LabelSlider::is_set() {
	return set;
}

bool LabelSlider::is_dragging() {
	return drag_proc;
}

QString LabelSlider::valueToString(double v) {
	if (qIsNaN(v)) {
		return "---";
	} else {
		switch (display_type) {
		case LABELSLIDER_FRAMENUMBER: return frame_to_timecode(v, config.timecode_view, frame_rate);
		case LABELSLIDER_PERCENT: return QString::number((v*100), 'f', decimal_places) + "%";
		}
		return QString::number(v, 'f', decimal_places);
	}
}

double LabelSlider::getPreviousValue() {
	return previous_value;
}

void LabelSlider::set_previous_value() {
	previous_value = internal_value;
}

void LabelSlider::set_color(QString c) {
	if (c.isEmpty()) c = "#ffc000";
	setStyleSheet("QLabel{color:" + c + ";text-decoration:underline;}QLabel:disabled{color:#808080;}");
}

double LabelSlider::value() {
	return internal_value;
}

void LabelSlider::set_default_value(double v) {
	default_value = v;
	if (!set) {
		set_value(v, false);
		set = false;
	}
}

void LabelSlider::set_minimum_value(double v) {
    min_value = v;
	min_enabled = true;
}

void LabelSlider::set_maximum_value(double v) {
	max_value = v;
	max_enabled = true;
}

void LabelSlider::mousePressEvent(QMouseEvent *ev) {
    // if primary button is clicked
    if (ev->button() == Qt::LeftButton && !drag_start) {

        // store initial value to be compared while dragging
		drag_start_value = internal_value;

        // alt + click sets labelslider to default value
		if (ev->modifiers() & Qt::AltModifier) {            

            // if the value is not already default, and there is a default to set
			if (internal_value != default_value && !qIsNaN(default_value)) {

                // cache current value
				set_previous_value();

                // set back to default
				set_value(default_value, true);

			}

		} else {

            // if value isn't valid, we set to a "default" of 0
			if (qIsNaN(internal_value)) internal_value = 0;

            // hide the cursor and store information about it for dragging
            set_active_cursor();

			drag_start = true;
			drag_start_x = cursor().pos().x();
			drag_start_y = cursor().pos().y();
		}

		emit clicked();

    } else {

        // handler if the user clicks with a non-primary button
        // prevents mouse from getting stuck in "dragging" mode
        mouseReleaseEvent(ev);

    }
}

void LabelSlider::mouseMoveEvent(QMouseEvent* event) {
	if (drag_start) {
        // if we're dragging

        // we don't actually start fully dragging until the cursor has moved
        // while the mouse is down, this helps prevent accidental drags
		drag_proc = true;

        // get amount cursor moved by
		double diff = (cursor().pos().x()-drag_start_x) + (drag_start_y-cursor().pos().y());

        // ctrl + drag drags in smaller increments
		if (event->modifiers() & Qt::ControlModifier) diff *= 0.01;

        // we'll also need to drag in smaller increments for a percent value
		if (display_type == LABELSLIDER_PERCENT) diff *= 0.01;

        // sets the value
		set_value(internal_value + diff, true);

        // keep the cursor in the same location while dragging
		cursor().setPos(drag_start_x, drag_start_y);
	}
}

void LabelSlider::mouseReleaseEvent(QMouseEvent*) {
    if (drag_start) {

        // unhide cursor
        set_default_cursor();

		drag_start = false;

        if (drag_proc) {
            // if we just finished fully dragging

			drag_proc = false;

			previous_value = drag_start_value;

			emit valueChanged();

		} else {

            // if the user didn't actually drag, and just clicked in one place,
            // we instead present a dialog prompt for the user to enter a
            // specific value

			double d = internal_value;

            if (display_type == LABELSLIDER_FRAMENUMBER) {

                // ask the user to enter a timecode
				QString s = QInputDialog::getText(
							this,
							tr("Set Value"),
							tr("New value:"),
							QLineEdit::Normal,
							valueToString(internal_value)
						);
				if (s.isEmpty()) return;

                // parse string timecode to a frame number
                d = timecode_to_frame(s, config.timecode_view, frame_rate);

			} else {

                // ask the user to enter a normal number value
				bool ok;

                // percentages are stored 0.0 - 1.0 but displayed as 0% - 100%
				d = QInputDialog::getDouble(
							this,
							tr("Set Value"),
							tr("New value:"),
							(display_type == LABELSLIDER_PERCENT) ? internal_value * 100 : internal_value,
							(min_enabled) ? min_value : INT_MIN,
							(max_enabled) ? max_value : INT_MAX,
							decimal_places,
							&ok
						);
				if (!ok) return;
				if (display_type == LABELSLIDER_PERCENT) d *= 0.01;
			}

            // if the value actually changed, trigger a change event
			if (d != internal_value) {
				set_previous_value();
				set_value(d, true);
			}
		}
    }
}

void LabelSlider::set_default_cursor() {
    setCursor(Qt::SizeHorCursor);
}

void LabelSlider::set_active_cursor() {
    setCursor(Qt::BlankCursor);
}