#!python
# -*- mode: python; coding: utf-8 -*-
# Last updated: <2016/11/06 23:11:51 +0900>
u"""
QSliderとQSpinBoxを1つのWidgetにまとめて並べてみるサンプル.

RGB/HSLのQSlider + QSpinBoxを用意して値を連動させる。
かつ、ビットマップ画像をGIMPの「着色」風に変更してみる。

Windows10 x64 + Python 2.7.11 + PySide 1.2.4
"""


import sys
from PySide.QtCore import *  # NOQA
from PySide.QtGui import *  # NOQA

IMG_FILE = "temp.png"


class LabelSliderSpinBox(QWidget):

    """Slider and SpinBox."""

    # Signalを用意
    valueChanged = Signal(int)

    def __init__(self, text, parent=None):
        """init."""
        super(LabelSliderSpinBox, self).__init__(parent)
        # self.setContentsMargins(0, 0, 0, 0)
        hl = QHBoxLayout()
        hl.setContentsMargins(0, 0, 0, 0)
        # hl.setSpacing(0)
        self.lbl = QLabel(text, self)
        self.sld = QSlider(Qt.Horizontal, self)
        self.spb = QSpinBox(self)
        hl.addWidget(self.lbl)
        hl.addWidget(self.sld)
        hl.addWidget(self.spb)
        self.setLayout(hl)
        self.sld.valueChanged[int].connect(self.changed_slider_value)
        self.spb.valueChanged[int].connect(self.changed_spinbox_value)

        # 用意したシグナルとスロットを関連付ける
        self.valueChanged[int].connect(self.changedValue)

    def setText(self, text):
        """set QLabel text."""
        self.lbl.setText(text)

    def setRange(self, start_v, end_v):
        """set range QSlider and QSpinBox."""
        self.sld.setRange(start_v, end_v)
        self.spb.setRange(start_v, end_v)

    def setValue(self, value):
        """set value to QSlider and QSpinBox."""
        self.sld.setValue(value)
        self.spb.setValue(value)

    def value(self):
        """get value."""
        return self.spb.value()

    def changed_slider_value(self, n):
        """changed slider value."""
        self.spb.setValue(n)

    def changed_spinbox_value(self, n):
        """changed spinbox value."""
        self.sld.setValue(n)
        self.valueChanged.emit(n)  # 値が変わったのでシグナルを発行

    # スロットを用意する
    @Slot(int)
    def changedValue(self, value):
        """changed slider or spinbox value."""
        pass
        # print("value = %d" % value)


class MyWidget(QWidget):

    """My Widget."""

    def __init__(self, *argv, **keywords):
        """init."""
        super(MyWidget, self).__init__(*argv, **keywords)
        self.setWindowTitle("Color Slider")

        self.event_ignore = False

        l = QVBoxLayout()

        # bitmap display label
        im = QImage(IMG_FILE)
        lbl = QLabel("", self)
        lbl.setPixmap(QPixmap.fromImage(im))
        l.addWidget(lbl)
        self.im = im
        self.lbl = lbl
        self.lum_im = self.make_lum_image(im)

        # color display button
        btn = QPushButton()
        btn.setFixedSize(32, 32)

        # set button background-color
        btn.setStyleSheet("QWidget { background-color: %s }"
                          % QColor(128, 128, 128).name())

        l.addWidget(btn)
        btn.clicked.connect(self.show_color_dialog)
        self.btn = btn

        # sliders
        data = [
            ("R", 0, 255, 128), ("G", 0, 255, 128), ("B", 0, 255, 128),
            ("H", 0, 360, 180), ("S", 0, 255, 128), ("L", 0, 255, 128)]
        self.sliders = []
        for (i, d) in enumerate(data):
            text, start_v, end_v, init_v = d
            w = LabelSliderSpinBox(text, self)
            w.setRange(start_v, end_v)
            w.setValue(init_v)
            l.addWidget(w)
            self.sliders.append(w)
            if i < 3:
                w.valueChanged.connect(self.changed_rgb)
            else:
                w.valueChanged.connect(self.changed_hsl)

        self.setLayout(l)

    def update_rgb_disp(self, col):
        """update RGB disp button."""
        # set background-color
        self.btn.setStyleSheet("QWidget { background-color: %s }"
                               % col.name())

    def set_sliders_rgb(self, col):
        """set RGB slider value."""
        r, g, b = col.red(), col.green(), col.blue()
        self.set_sliders(0, (r, g, b))

    def set_sliders_hsl(self, col):
        """set HSL slider value."""
        h, s, l = col.hslHue(), col.hslSaturation(), col.lightness()
        self.set_sliders(3, (h, s, l))

    def set_sliders(self, idx, v):
        """set 3 slider value."""
        for i in range(3):
            if self.sliders[idx + i].value() != v[i]:
                self.sliders[idx + i].setValue(v[i])

    def get_sliders(self, idx):
        """get 3 slider value."""
        v = []
        for i in range(3):
            v.append(self.sliders[idx + i].value())
        return tuple(v)

    def changed_rgb(self, _):
        """changed RGB value."""
        if not self.event_ignore:
            self.event_ignore = True
            r, g, b = self.get_sliders(0)
            col = QColor(r, g, b)
            self.set_sliders_hsl(col)
            self.update_rgb_disp(col)
            self.change_pixmap_color(self.lum_im)
            self.event_ignore = False

    def changed_hsl(self, _):
        """changed HSL value."""
        if not self.event_ignore:
            self.event_ignore = True
            h, s, l = self.get_sliders(3)
            col = QColor()
            col.setHsl(h, s, l)
            self.set_sliders_rgb(col)
            self.update_rgb_disp(col)
            self.change_pixmap_color(self.lum_im)
            self.event_ignore = False

    def show_color_dialog(self):
        """open QColorDialog."""
        col = QColorDialog.getColor()
        if col.isValid():
            self.set_sliders_rgb(col)

    def make_lum_image(self, im):
        """make luminance image."""
        w, h = im.size().width(), im.size().height()
        dst = []
        for y in range(h):
            d = []
            for x in range(w):
                c = im.pixel(x, y)
                r, g, b = qRed(c), qGreen(c), qBlue(c)
                # get luminance
                l = int(0.2126 * r + 0.7152 * g + 0.0722 * b)
                l = max(0, min(l, 255))
                d.append((l, qAlpha(c)))
            dst.append(d)
        return dst

    def change_pixmap_color(self, src):
        """change QPixmap color."""
        b_h, b_s, b_l = self.get_sliders(3)
        w, h = len(src), len(src[0])
        dst = QImage(w, h, QImage.Format_ARGB32)
        c2 = QColor()
        for y in range(h):
            for x in range(w):
                l, a = src[y][x]
                if b_l > 128:
                    l *= (255.0 - b_l) / 127.0
                    l += (255.0 - ((255 - b_l) * 255.0 / 127.0))
                elif b_l < 128:
                    l *= b_l / 128.0
                l = int(l)
                if l < 0:
                    l = 0
                if l > 255:
                    l = 255
                c2.setHsl(b_h, b_s, l, a)
                dst.setPixel(x, y, c2.rgba())
        self.lbl.setPixmap(QPixmap.fromImage(dst))


def main():
    """Main."""
    app = QApplication(sys.argv)
    w = MyWidget()
    w.show()
    sys.exit(app.exec_())


if __name__ == '__main__':
    main()