import bgl
import blf
import bpy


'''
Copyright (c) 2019

Jorge Hernández - Meléndez Saiz
[email protected]

This program 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.

This program 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 this program. If not, see <http://www.gnu.org/licenses/>.

'''


font_info = {
    "font_id": 0,
    "handler": None,
}


def init():
    font_info["font_id"] = 0

    # set the font drawing routine to run every frame
    font_info["handler"] = bpy.types.SpaceView3D.draw_handler_add(
        draw_callback_px, (None, None), 'WINDOW', 'POST_PIXEL')


def draw_callback_px(self, context):
    """Draw on the viewports"""
    # BLF drawing routine
    font_id = font_info["font_id"]

    offsetTextInTop = 86
    height = bpy.context.area.height - offsetTextInTop

    toolbarWidth = bpy.context.area.regions[1].width

    blf.position(font_id, 20+toolbarWidth, height, 0)

    fontSize = 11
    blf.size(font_id, fontSize, 72)

    # sombra:
    # el level tiene que ser 3, 5 o 0
    level = 0
    r = 0.0
    g = 0.0
    b = 0.0
    a = 1.0

    blf.shadow(font_id, level, r, g, b, a)
    blf.shadow_offset(font_id, 2, 1)

    # esto se calcula cada pasada de dibujado del viewport:
    motor = bpy.context.scene.render.engine
    if motor == 'BLENDER_EEVEE':
        blf.draw(font_id, "Eevee")
    elif motor == 'BLENDER_WORKBENCH':
        blf.draw(font_id, "Workbench")
    elif motor == 'CYCLES':
        blf.draw(font_id, "Cycles")
    else:
        blf.draw(font_id, "")


if __name__ == '__main__':
    init()