"""Strip viewer and related widgets.

The classes in this file implement the StripViewer shown in the top two thirds
of the main Pynche window. It consists of three StripWidgets which display
the variations in red, green, and blue respectively of the currently selected
r/g/b color value.

Each StripWidget shows the color variations that are reachable by varying an
axis of the currently selected color. So for example, if the color is

 (R,G,B)=(127,163,196)

then the Red variations show colors from (0,163,196) to (255,163,196), the
Green variations show colors from (127,0,196) to (127,255,196), and the Blue
variations show colors from (127,163,0) to (127,163,255).

The selected color is always visible in all three StripWidgets, and in fact
each StripWidget highlights the selected color, and has an arrow pointing to
the selected chip, which includes the value along that particular axis.

Clicking on any chip in any StripWidget selects that color, and updates all
arrows and other windows. By toggling on Update while dragging, Pynche will
select the color under the cursor while you drag it, but be forewarned that
this can be slow.
"""

from tkinter import *
import ColorDB

# Load this script into the Tcl interpreter and call it in
# StripWidget.set_color(). This is about as fast as it can be with the
# current _tkinter.c interface, which doesn't support Tcl Objects.
TCLPROC = '''\
proc setcolor {canv colors} {
 set i 1
 foreach c $colors {
 $canv itemconfigure $i -fill $c -outline $c
 incr i
 }
}
'''

# Tcl event types
BTNDOWN = 4
BTNUP = 5
BTNDRAG = 6

SPACE = ' '



def constant(numchips):
 step = 255.0 / (numchips - 1)
 start = 0.0
 seq = []
 while numchips > 0:
 seq.append(int(start))
 start = start + step
 numchips = numchips - 1
 return seq

# red variations, green+blue = cyan constant
def constant_red_generator(numchips, red, green, blue):
 seq = constant(numchips)
 return list(zip([red] * numchips, seq, seq))

# green variations, red+blue = magenta constant
def constant_green_generator(numchips, red, green, blue):
 seq = constant(numchips)
 return list(zip(seq, [green] * numchips, seq))

# blue variations, red+green = yellow constant
def constant_blue_generator(numchips, red, green, blue):
 seq = constant(numchips)
 return list(zip(seq, seq, [blue] * numchips))

# red variations, green+blue = cyan constant
def constant_cyan_generator(numchips, red, green, blue):
 seq = constant(numchips)
 return list(zip(seq, [green] * numchips, [blue] * numchips))

# green variations, red+blue = magenta constant
def constant_magenta_generator(numchips, red, green, blue):
 seq = constant(numchips)
 return list(zip([red] * numchips, seq, [blue] * numchips))

# blue variations, red+green = yellow constant
def constant_yellow_generator(numchips, red, green, blue):
 seq = constant(numchips)
 return list(zip([red] * numchips, [green] * numchips, seq))



class LeftArrow:
 _ARROWWIDTH = 30
 _ARROWHEIGHT = 15
 _YOFFSET = 13
 _TEXTYOFFSET = 1
 _TAG = ('leftarrow',)

 def __init__(self, canvas, x):
 self._canvas = canvas
 self.__arrow, self.__text = self._create(x)
 self.move_to(x)

 def _create(self, x):
 arrow = self._canvas.create_line(
 x, self._ARROWHEIGHT + self._YOFFSET,
 x, self._YOFFSET,
 x + self._ARROWWIDTH, self._YOFFSET,
 arrow='first',
 width=3.0,
 tags=self._TAG)
 text = self._canvas.create_text(
 x + self._ARROWWIDTH + 13,
 self._ARROWHEIGHT - self._TEXTYOFFSET,
 tags=self._TAG,
 text='128')
 return arrow, text

 def _x(self):
 coords = list(self._canvas.coords(self._TAG))
 assert coords
 return coords[0]

 def move_to(self, x):
 deltax = x - self._x()
 self._canvas.move(self._TAG, deltax, 0)

 def set_text(self, text):
 self._canvas.itemconfigure(self.__text, text=text)


class RightArrow(LeftArrow):
 _TAG = ('rightarrow',)

 def _create(self, x):
 arrow = self._canvas.create_line(
 x, self._YOFFSET,
 x + self._ARROWWIDTH, self._YOFFSET,
 x + self._ARROWWIDTH, self._ARROWHEIGHT + self._YOFFSET,
 arrow='last',
 width=3.0,
 tags=self._TAG)
 text = self._canvas.create_text(
 x - self._ARROWWIDTH + 15, # BAW: kludge
 self._ARROWHEIGHT - self._TEXTYOFFSET,
 justify=RIGHT,
 text='128',
 tags=self._TAG)
 return arrow, text

 def _x(self):
 coords = list(self._canvas.coords(self._TAG))
 assert coords
 return coords[0] + self._ARROWWIDTH



class StripWidget:
 _CHIPHEIGHT = 50
 _CHIPWIDTH = 10
 _NUMCHIPS = 40

 def __init__(self, switchboard,
 master = None,
 chipwidth = _CHIPWIDTH,
 chipheight = _CHIPHEIGHT,
 numchips = _NUMCHIPS,
 generator = None,
 axis = None,
 label = '',
 uwdvar = None,
 hexvar = None):
 # instance variables
 self.__generator = generator
 self.__axis = axis
 self.__numchips = numchips
 assert self.__axis in (0, 1, 2)
 self.__uwd = uwdvar
 self.__hexp = hexvar
 # the last chip selected
 self.__lastchip = None
 self.__sb = switchboard

 canvaswidth = numchips * (chipwidth + 1)
 canvasheight = chipheight + 43 # BAW: Kludge

 # create the canvas and pack it
 canvas = self.__canvas = Canvas(master,
 width=canvaswidth,
 height=canvasheight,
## borderwidth=2,
## relief=GROOVE
 )

 canvas.pack()
 canvas.bind('<ButtonPress-1>', self.__select_chip)
 canvas.bind('<ButtonRelease-1>', self.__select_chip)
 canvas.bind('<B1-Motion>', self.__select_chip)

 # Load a proc into the Tcl interpreter. This is used in the
 # set_color() method to speed up setting the chip colors.
 canvas.tk.eval(TCLPROC)

 # create the color strip
 chips = self.__chips = []
 x = 1
 y = 30
 tags = ('chip',)
 for c in range(self.__numchips):
 color = 'grey'
 canvas.create_rectangle(
 x, y, x+chipwidth, y+chipheight,
 fill=color, outline=color,
 tags=tags)
 x = x + chipwidth + 1 # for outline
 chips.append(color)

 # create the strip label
 self.__label = canvas.create_text(
 3, y + chipheight + 8,
 text=label,
 anchor=W)

 # create the arrow and text item
 chipx = self.__arrow_x(0)
 self.__leftarrow = LeftArrow(canvas, chipx)

 chipx = self.__arrow_x(len(chips) - 1)
 self.__rightarrow = RightArrow(canvas, chipx)

 def __arrow_x(self, chipnum):
 coords = self.__canvas.coords(chipnum+1)
 assert coords
 x0, y0, x1, y1 = coords
 return (x1 + x0) / 2.0

 # Invoked when one of the chips is clicked. This should just tell the
 # switchboard to set the color on all the output components
 def __select_chip(self, event=None):
 x = event.x
 y = event.y
 canvas = self.__canvas
 chip = canvas.find_overlapping(x, y, x, y)
 if chip and (1 <= chip[0] <= self.__numchips):
 color = self.__chips[chip[0]-1]
 red, green, blue = ColorDB.rrggbb_to_triplet(color)
 etype = int(event.type)
 if (etype == BTNUP or self.__uwd.get()):
 # update everyone
 self.__sb.update_views(red, green, blue)
 else:
 # just track the arrows
 self.__trackarrow(chip[0], (red, green, blue))

 def __trackarrow(self, chip, rgbtuple):
 # invert the last chip
 if self.__lastchip is not None:
 color = self.__canvas.itemcget(self.__lastchip, 'fill')
 self.__canvas.itemconfigure(self.__lastchip, outline=color)
 self.__lastchip = chip
 # get the arrow's text
 coloraxis = rgbtuple[self.__axis]
 if self.__hexp.get():
 # hex
 text = hex(coloraxis)
 else:
 # decimal
 text = repr(coloraxis)
 # move the arrow, and set its text
 if coloraxis <= 128:
 # use the left arrow
 self.__leftarrow.set_text(text)
 self.__leftarrow.move_to(self.__arrow_x(chip-1))
 self.__rightarrow.move_to(-100)
 else:
 # use the right arrow
 self.__rightarrow.set_text(text)
 self.__rightarrow.move_to(self.__arrow_x(chip-1))
 self.__leftarrow.move_to(-100)
 # and set the chip's outline
 brightness = ColorDB.triplet_to_brightness(rgbtuple)
 if brightness <= 128:
 outline = 'white'
 else:
 outline = 'black'
 self.__canvas.itemconfigure(chip, outline=outline)


 def update_yourself(self, red, green, blue):
 assert self.__generator
 i = 1
 chip = 0
 chips = self.__chips = []
 tk = self.__canvas.tk
 # get the red, green, and blue components for all chips
 for t in self.__generator(self.__numchips, red, green, blue):
 rrggbb = ColorDB.triplet_to_rrggbb(t)
 chips.append(rrggbb)
 tred, tgreen, tblue = t
 if tred <= red and tgreen <= green and tblue <= blue:
 chip = i
 i = i + 1
 # call the raw tcl script
 colors = SPACE.join(chips)
 tk.eval('setcolor %s {%s}' % (self.__canvas._w, colors))
 # move the arrows around
 self.__trackarrow(chip, (red, green, blue))

 def set(self, label, generator):
 self.__canvas.itemconfigure(self.__label, text=label)
 self.__generator = generator


class StripViewer:
 def __init__(self, switchboard, master=None):
 self.__sb = switchboard
 optiondb = switchboard.optiondb()
 # create a frame inside the master.
 frame = Frame(master, relief=RAISED, borderwidth=1)
 frame.grid(row=1, column=0, columnspan=2, sticky='NSEW')
 # create the options to be used later
 uwd = self.__uwdvar = BooleanVar()
 uwd.set(optiondb.get('UPWHILEDRAG', 0))
 hexp = self.__hexpvar = BooleanVar()
 hexp.set(optiondb.get('HEXSTRIP', 0))
 # create the red, green, blue strips inside their own frame
 frame1 = Frame(frame)
 frame1.pack(expand=YES, fill=BOTH)
 self.__reds = StripWidget(switchboard, frame1,
 generator=constant_cyan_generator,
 axis=0,
 label='Red Variations',
 uwdvar=uwd, hexvar=hexp)

 self.__greens = StripWidget(switchboard, frame1,
 generator=constant_magenta_generator,
 axis=1,
 label='Green Variations',
 uwdvar=uwd, hexvar=hexp)

 self.__blues = StripWidget(switchboard, frame1,
 generator=constant_yellow_generator,
 axis=2,
 label='Blue Variations',
 uwdvar=uwd, hexvar=hexp)

 # create a frame to contain the controls
 frame2 = Frame(frame)
 frame2.pack(expand=YES, fill=BOTH)
 frame2.columnconfigure(0, weight=20)
 frame2.columnconfigure(2, weight=20)

 padx = 8

 # create the black button
 blackbtn = Button(frame2,
 text='Black',
 command=self.__toblack)
 blackbtn.grid(row=0, column=0, rowspan=2, sticky=W, padx=padx)

 # create the controls
 uwdbtn = Checkbutton(frame2,
 text='Update while dragging',
 variable=uwd)
 uwdbtn.grid(row=0, column=1, sticky=W)
 hexbtn = Checkbutton(frame2,
 text='Hexadecimal',
 variable=hexp,
 command=self.__togglehex)
 hexbtn.grid(row=1, column=1, sticky=W)

 # XXX: ignore this feature for now; it doesn't work quite right yet

## gentypevar = self.__gentypevar = IntVar()
## self.__variations = Radiobutton(frame,
## text='Variations',
## variable=gentypevar,
## value=0,
## command=self.__togglegentype)
## self.__variations.grid(row=0, column=1, sticky=W)
## self.__constants = Radiobutton(frame,
## text='Constants',
## variable=gentypevar,
## value=1,
## command=self.__togglegentype)
## self.__constants.grid(row=1, column=1, sticky=W)

 # create the white button
 whitebtn = Button(frame2,
 text='White',
 command=self.__towhite)
 whitebtn.grid(row=0, column=2, rowspan=2, sticky=E, padx=padx)

 def update_yourself(self, red, green, blue):
 self.__reds.update_yourself(red, green, blue)
 self.__greens.update_yourself(red, green, blue)
 self.__blues.update_yourself(red, green, blue)

 def __togglehex(self, event=None):
 red, green, blue = self.__sb.current_rgb()
 self.update_yourself(red, green, blue)

## def __togglegentype(self, event=None):
## which = self.__gentypevar.get()
## if which == 0:
## self.__reds.set(label='Red Variations',
## generator=constant_cyan_generator)
## self.__greens.set(label='Green Variations',
## generator=constant_magenta_generator)
## self.__blues.set(label='Blue Variations',
## generator=constant_yellow_generator)
## elif which == 1:
## self.__reds.set(label='Red Constant',
## generator=constant_red_generator)
## self.__greens.set(label='Green Constant',
## generator=constant_green_generator)
## self.__blues.set(label='Blue Constant',
## generator=constant_blue_generator)
## else:
## assert 0
## self.__sb.update_views_current()

 def __toblack(self, event=None):
 self.__sb.update_views(0, 0, 0)

 def __towhite(self, event=None):
 self.__sb.update_views(255, 255, 255)

 def save_options(self, optiondb):
 optiondb['UPWHILEDRAG'] = self.__uwdvar.get()
 optiondb['HEXSTRIP'] = self.__hexpvar.get()