import enum
import math
import cairo

from hexagram.dial import Dial

class SpeedUnits(enum.Enum):
    KPH = 0
    MPH = 1

class Speedo(Dial):
    __slots__ = 'units',

    MIN_ANGLE = 232.0 * (math.pi / 180.0)
    MAX_ANGLE = 488.0 * (math.pi / 180.0)

    FONT_FACE = "Muli"

    def __init__(self, x: float, y: float, radius: float, max_value: float, units: SpeedUnits=SpeedUnits.KPH):
        super().__init__(x, y, radius, self.MIN_ANGLE, self.MAX_ANGLE, 0, max_value)

        self.value = 0
        self.units = units

    def draw_bg(self, cr: cairo.Context):
        super().draw_bg(cr)

        cr.select_font_face(self.FONT_FACE,
                            cairo.FontSlant.ITALIC,
                            cairo.FontWeight.BOLD)

        cr.set_font_size(self.radius * 0.1)

        cr.set_source_rgb(1, 1, 1)

        for speed in range(0, int(self.max_value)+1, 5):
            min_radius = 0.81 if speed % 10 == 0 else 0.82

            cr.set_line_width(6.0 if speed % 10 == 0 else 2.0)
            self.draw_mark(cr, min_radius, 0.87, speed)

        for speed in range(0, int(self.max_value)+1, 20):
            self.draw_number(cr, 0.68, speed, "%d" % int(speed))

    def _draw_text(self, cr: cairo.Context, x: float, y: float, text: str, size: float):
        cr.select_font_face("Muli",
                            cairo.FontSlant.ITALIC,
                            cairo.FontWeight.BOLD)

        cr.set_font_size(self.radius * size)
        cr.set_source_rgb(1, 0.4, 1)

        extents = cr.text_extents(text)
        width   = extents[2] - extents[0]
        height  = extents[3] - extents[1]

        cr.move_to(x - width / 2, y + height / 4)
        cr.show_text(text)

    def draw_fg(self, cr: cairo.Context):
        super().draw_fg(cr)

        self._draw_text(cr, self.x, self.y, "%d" % self.value, 0.32)
        self._draw_text(cr, self.x, self.y + self.radius * 0.2, 'mph', 0.1)