# Copyright 2007 Mitchell N. Charity
# Copyright 2009 Walter Bender
#
# This file is part of Ruler.
#
# Ruler 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 3 of the License, or
# (at your option) any later version.
#
# Ruler 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 Ruler.  If not, see <http://www.gnu.org/licenses/>

import cairo

from util import mm, dimensions_mm, set_background_color, write, get_hardware

import os.path
from gettext import gettext as _

class ScreenOfRulers():
    def __init__(self, font, font_bold, w, h):
        self.font = font
        self.font_bold = font_bold
        self.w = w
        self.h = h
        self.hw = get_hardware()

    def draw(self, c, dpi):
        set_background_color(c, self.w, self.h)

        nw, nh = dimensions_mm(dpi, self.w, self.h)
        c.set_antialias(cairo.ANTIALIAS_GRAY)

        self.draw_ruler_pair(c, dpi, mm(dpi, 20))

        # only calculate offsets if on an OLPC XO-1
        if self.hw[0:2] == 'XO':
            offset_of_xo_side_from_screen = mm(dpi, -38.5) #XXX needs checking
            c.move_to(offset_of_xo_side_from_screen,  mm(dpi, 65))
            self.draw_cm_ruler(c, dpi, 180)
            
            c.save()
            c.move_to(mm(dpi, 20), mm(dpi, 75))
            write(c, _('Use this ruler from the outside edge of the computer.'),
                  self.font, mm(dpi, 4))
            c.restore()

            offset_of_molding_from_screen = mm(dpi, -0.4) #XXX +- 0.2 ??
            c.move_to(offset_of_molding_from_screen,  mm(dpi, 95))
            self.draw_cm_ruler(c, dpi, 150)

        else:
            offset_of_xo_side_from_screen = mm(dpi, 0)
            c.move_to(offset_of_xo_side_from_screen,  mm(dpi, 65))
            self.draw_cm_ruler(c, dpi, int(nw / 10 * 10))
            
    def draw_ruler_pair(self, c, dpi, y):

        c.move_to(mm(dpi, 10), y)
        self.connect_rulers(c, dpi)

        c.move_to(mm(dpi, 10), y)
        self.draw_cm_ruler(c, dpi)

        c.move_to(mm(dpi, 10), y+mm(dpi, 10))
        self.draw_mm_ruler(c, dpi)
        
    def connect_rulers(self, c, dpi):
        c.save()
        c.set_line_cap(cairo.LINE_CAP_SQUARE)
        c.translate(*c.get_current_point())

        c.set_line_width(1)
        for xm in range(0, 130+1, 10):
            c.move_to(mm(dpi, xm), 0)
            c.rel_line_to(0, mm(dpi, 10))
        c.stroke()

        c.set_line_width(2)
        c.move_to(0, 0)
        c.rel_line_to(0, mm(dpi, 10))
        c.stroke()

        c.restore()

    def draw_cm_ruler(self, c, dpi, width=130):

        c.save()
        c.set_line_cap(cairo.LINE_CAP_SQUARE)
        c.translate(*c.get_current_point())

        c.set_line_width(5)
        c.move_to(0, 0)
        c.line_to(mm(dpi, width), 0)
        for x in [mm(dpi, xm) for xm in range(0, width+1, 10)]:
            c.move_to(x, 0)
            c.rel_line_to(0, mm(dpi, -3))
        c.stroke()

        for x, xm in [(mm(dpi, xm), xm) for xm in range(0, width+1, 10)]:
            n = xm/10
            c.move_to(x, mm(dpi, -4))
            write(c, "%d" % n, self.font_bold, mm(dpi, 2.5), centered=True)
            
        c.move_to(mm(dpi, 1.5), mm(dpi, -4))
        write(c, "cm", self.font_bold, mm(dpi, 2))

        c.restore()

    def draw_mm_ruler(self, c, dpi, width=130):

        c.save()
        c.set_line_cap(cairo.LINE_CAP_SQUARE)
        c.translate(*c.get_current_point())

        c.move_to(0, 0)
        c.set_line_width(4)
        c.line_to(mm(dpi, width), 0)
        for x in [mm(dpi, xm) for xm in range(0, width+1, 10)]:
            c.move_to(x, 0)
            c.rel_line_to(0, mm(dpi, 3))
        c.stroke()

        c.set_line_width(3)
        for x in [mm(dpi, xm) for xm in range(0, width, 5)]:
            c.move_to(x, 0)
            c.rel_line_to(0, mm(dpi, 2.2))
        for x in [mm(dpi, xm) for xm in range(0, width, 1)]:
            c.move_to(x, 0)
            c.rel_line_to(0, mm(dpi, 2))
        c.stroke()

        base = mm(dpi, 7)
        for x, xm in [(mm(dpi, xm), xm) for xm in range(0, width+1, 10)]:
            c.move_to(x, base)
            write(c, "%d" % xm, self.font, mm(dpi, 2), centered=True)
            
        c.move_to(mm(dpi, 1.2), base)
        write(c, "mm", self.font, mm(dpi, 1.5))

        c.restore()