Inkycal/inkycal/main.py

#!python3
# -*- coding: utf-8 -*-

"""
Main class for inkycal Project
Copyright by aceisace
"""

import glob
import hashlib
import json
import traceback
from logging.handlers import RotatingFileHandler

import arrow
import numpy

from inkycal.custom import *
from inkycal.display import Display
from inkycal.modules.inky_image import Inkyimage as Images

from PIL import Image

# On the console, set a logger to show only important logs
# (level ERROR or higher)
stream_handler = logging.StreamHandler()
stream_handler.setLevel(logging.ERROR)

on_rtd = os.environ.get('READTHEDOCS') == 'True'
if on_rtd:
    logging.basicConfig(
        level=logging.INFO,
        format='%(asctime)s | %(name)s |  %(levelname)s: %(message)s',
        datefmt='%d-%m-%Y %H:%M:%S',
        handlers=[stream_handler])

else:

    if not os.path.exists(f'{top_level}/logs'):
        os.mkdir(f'{top_level}/logs')

    # Save all logs to a file, which contains more detailed output
    logging.basicConfig(
        level=logging.INFO,
        format='%(asctime)s | %(name)s |  %(levelname)s: %(message)s',
        datefmt='%d-%m-%Y %H:%M:%S',
        handlers=[

            stream_handler,  # add stream handler from above

            RotatingFileHandler(  # log to a file too
                f'{top_level}/logs/inkycal.log',  # file to log
                maxBytes=2097152,  # 2MB max filesize
                backupCount=5  # create max 5 log files
            )
        ]
    )

# Show less logging for PIL module
logging.getLogger("PIL").setLevel(logging.WARNING)

logger = logging.getLogger(__name__)


# TODO: autostart -> supervisor?

class Inkycal:
    """Inkycal main class

    Main class of Inkycal, test and run the main Inkycal program.

    Args:
      - settings_path = str -> the full path to your settings.json file
        if no path is given, tries looking for settings file in /boot folder.
      - render = bool (True/False) -> show the image on the epaper display?

    Attributes:
      - optimize = True/False. Reduce number of colours on the generated image
        to improve rendering on E-Papers. Set this to False for 9.7" E-Paper.
    """

    def __init__(self, settings_path=None, render=True):
        """Initialise Inkycal"""

        self._release = '2.0.2'

        # Check if render was set correctly
        if render not in [True, False]:
            raise Exception(f'render must be True or False, not "{render}"')
        self.render = render

        # load settings file - throw an error if file could not be found
        if settings_path:
            try:
                with open(settings_path) as settings_file:
                    settings = json.load(settings_file)
                    self.settings = settings

            except FileNotFoundError:
                raise SettingsFileNotFoundError

        else:
            try:
                with open('/boot/settings.json') as settings_file:
                    settings = json.load(settings_file)
                    self.settings = settings

            except FileNotFoundError:
                raise SettingsFileNotFoundError

        if not os.path.exists(image_folder):
            os.mkdir(image_folder)

        # Option to use epaper image optimisation, reduces colours
        self.optimize = True

        # Load drivers if image should be rendered
        if self.render:
            # Init Display class with model in settings file
            # from inkycal.display import Display
            self.Display = Display(settings["model"])

            # check if colours can be rendered
            self.supports_colour = True if 'colour' in settings['model'] else False

            # get calibration hours
            self._calibration_hours = self.settings['calibration_hours']

            # init calibration state
            self._calibration_state = False

        # Load and intialize modules specified in the settings file
        self._module_number = 1
        for module in settings['modules']:
            module_name = module['name']
            try:
                loader = f'from inkycal.modules import {module_name}'
                # print(loader)
                exec(loader)
                setup = f'self.module_{self._module_number} = {module_name}({module})'
                # print(setup)
                exec(setup)
                logger.info(('name : {name} size : {width}x{height} px'.format(
                    name=module_name,
                    width=module['config']['size'][0],
                    height=module['config']['size'][1])))

                self._module_number += 1

            # If a module was not found, print an error message
            except ImportError:
                print(f'Could not find module: "{module}". Please try to import manually')

            # If something unexpected happened, show the error message
            except Exception as e:
                print(str(e))

        # Path to store images
        self.image_folder = image_folder

        # Remove old hashes
        self._remove_hashes(self.image_folder)

        # Give an OK message
        print('loaded inkycal')

    def countdown(self, interval_mins=None):
        """Returns the remaining time in seconds until next display update"""

        # Check if empty, if empty, use value from settings file
        if interval_mins is None:
            interval_mins = self.settings["update_interval"]

        # Find out at which minutes the update should happen
        now = arrow.now()
        update_timings = [(60 - int(interval_mins) * updates) for updates in
                          range(60 // int(interval_mins))][::-1]

        # Calculate time in mins until next update
        minutes = [_ for _ in update_timings if _ >= now.minute][0] - now.minute

        # Print the remaining time in mins until next update
        print(f'{minutes} minutes left until next refresh')

        # Calculate time in seconds until next update
        remaining_time = minutes * 60 + (60 - now.second)

        # Return seconds until next update
        return remaining_time

    def test(self):
        """Tests if Inkycal can run without issues.

        Attempts to import module names from settings file. Loads the config
        for each module and initializes the module. Tries to run the module and
        checks if the images could be generated correctly.

        Generated images can be found in the /images folder of Inkycal.
        """

        print(f'Inkycal version: v{self._release}')
        print(f'Selected E-paper display: {self.settings["model"]}')

        # store module numbers in here
        errors = []

        # short info for info-section
        self.info = f"{arrow.now().format('D MMM @ HH:mm')}  "

        for number in range(1, self._module_number):
            name = eval(f"self.module_{number}.name")
            module = eval(f'self.module_{number}')
            print(f'generating image(s) for {name}...', end="")
            try:
                black, colour = module.generate_image()
                black.save(f"{self.image_folder}module{number}_black.png", "PNG")
                colour.save(f"{self.image_folder}module{number}_colour.png", "PNG")
                print('OK!')
            except:
                errors.append(number)
                self.info += f"module {number}: Error!  "
                print('Error!')
                print(traceback.format_exc())

        if errors:
            print('Error/s in modules:', *errors)
        del errors

        self._assemble()

    def _image_hash(self, _in):
        """Create a md5sum of a path or a bytes stream."""
        if not isinstance(_in, str):
            image_bytes = _in.tobytes()
        else:
            try:
                with open(_in) as i:
                    return i.read()
            except FileNotFoundError:
                image_bytes = None
        return hashlib.md5(image_bytes).hexdigest() if image_bytes else ""

    def _remove_hashes(self, basepath):
        for _file in glob.glob(f"{basepath}/*.hash"):
            try:
                os.remove(_file)
            except:
                pass

    def _write_image_hash(self, path, _in):
        """Write hash to a file."""
        with open(path, "w") as o:
            o.write(self._image_hash(_in))

    def _needs_image_update(self, _list):
        """Check if any image has been updated or not.
        Input a list of tuples(str, image)."""
        res = False
        for item in _list:
            _a = self._image_hash(item[0])
            _b = self._image_hash(item[1])
            print("{f1}:{h1} -> {h2}".format(f1=item[0], h1=_a, h2=_b))
            if _a != _b:
                res = True
                self._write_image_hash(item[0], item[1])
            print("Refresh needed: {a}".format(a=res))
        return res


    def run(self):
        """Runs main program in nonstop mode.

        Uses an infinity loop to run Inkycal nonstop. Inkycal generates the image
        from all modules, assembles them in one image, refreshed the E-Paper and
        then sleeps until the next sheduled update.
        """

        # Get the time of initial run
        runtime = arrow.now()

        # Function to flip images upside down
        upside_down = lambda image: image.rotate(180, expand=True)

        # Count the number of times without any errors
        counter = 0

        print(f'Inkycal version: v{self._release}')
        print(f'Selected E-paper display: {self.settings["model"]}')

        while True:
            current_time = arrow.now(tz=get_system_tz())
            print(f"Date: {current_time.format('D MMM YY')} | "
                  f"Time: {current_time.format('HH:mm')}")
            print('Generating images for all modules...', end='')

            errors = []  # store module numbers in here

            # short info for info-section
            if not self.settings.get('image_hash', False):
                self.info = f"{current_time.format('D MMM @ HH:mm')}  "
            else:
                self.info = ""

            for number in range(1, self._module_number):

                # name = eval(f"self.module_{number}.name")
                module = eval(f'self.module_{number}')

                try:
                    black, colour = module.generate_image()
                    black.save(f"{self.image_folder}module{number}_black.png", "PNG")
                    colour.save(f"{self.image_folder}module{number}_colour.png", "PNG")
                    self.info += f"module {number}: OK  "
                except:
                    errors.append(number)
                    print('error!')
                    print(traceback.format_exc())
                    self.info += f"module {number}: error!  "
                    logger.exception(f'Exception in module {number}')

            if errors:
                print('error/s in modules:', *errors)
                counter = 0
            else:
                counter += 1
                print('successful')
            del errors

            # Assemble image from each module - add info section if specified
            self._assemble()

            # Check if image should be rendered
            if self.render:
                display = self.Display

                self._calibration_check()
                if self._calibration_state:
                    # after calibration we have to forcefully rewrite the screen
                    self._remove_hashes(self.image_folder)

                if self.supports_colour:
                    im_black = Image.open(f"{self.image_folder}canvas.png")
                    im_colour = Image.open(f"{self.image_folder}canvas_colour.png")

                    # Flip the image by 180° if required
                    if self.settings['orientation'] == 180:
                        im_black = upside_down(im_black)
                        im_colour = upside_down(im_colour)

                    # render the image on the display
                    if not self.settings.get('image_hash', False) or self._needs_image_update([
                      (f"{self.image_folder}/canvas.png.hash", im_black),
                      (f"{self.image_folder}/canvas_colour.png.hash", im_colour)
                    ]):
                        # render the image on the display
                        display.render(im_black, im_colour)

                # Part for black-white ePapers
                elif not self.supports_colour:

                    im_black = self._merge_bands()

                    # Flip the image by 180° if required
                    if self.settings['orientation'] == 180:
                        im_black = upside_down(im_black)

                    if not self.settings.get('image_hash', False) or self._needs_image_update([
                      (f"{self.image_folder}/canvas.png.hash", im_black),
                    ]):
                        display.render(im_black)

            print(f'\nNo errors since {counter} display updates \n'
                  f'program started {runtime.humanize()}')

            sleep_time = self.countdown()
            time.sleep(sleep_time)

    @staticmethod
    def _merge_bands():
        """Merges black and coloured bands for black-white ePapers
        returns the merged image
        """

        im1_path, im2_path = image_folder + 'canvas.png', image_folder + 'canvas_colour.png'

        # If there is an image for black and colour, merge them
        if os.path.exists(im1_path) and os.path.exists(im2_path):

            im1 = Image.open(im1_path).convert('RGBA')
            im2 = Image.open(im2_path).convert('RGBA')

            im1 = Images.merge(im1, im2)

        # If there is no image for the coloured-band, return the bw-image
        elif os.path.exists(im1_path) and not os.path.exists(im2_path):
            im1 = Image.open(im1_path).convert('RGBA')

        else:
            raise FileNotFoundError("Inkycal cannot find images to merge")

        return im1

    def _assemble(self):
        """Assembles all sub-images to a single image"""

        # Create 2 blank images with the same resolution as the display
        width, height = Display.get_display_size(self.settings["model"])

        # Since Inkycal runs in vertical mode, switch the height and width
        width, height = height, width

        im_black = Image.new('RGB', (width, height), color='white')
        im_colour = Image.new('RGB', (width, height), color='white')

        # Set cursor for y-axis
        im1_cursor = 0
        im2_cursor = 0

        for number in range(1, self._module_number):

            # get the path of the current module's generated images
            im1_path = f"{self.image_folder}module{number}_black.png"
            im2_path = f"{self.image_folder}module{number}_colour.png"

            # Check if there is an image for the black band
            if os.path.exists(im1_path):

                # Get actual size of image
                im1 = Image.open(im1_path).convert('RGBA')
                im1_size = im1.size

                # Get the size of the section
                section_size = [i for i in self.settings['modules'] if i['position'] == number][0]['config']['size']

                # Calculate coordinates to center the image
                x = int((section_size[0] - im1_size[0]) / 2)

                # If this is the first module, use the y-offset
                if im1_cursor == 0:
                    y = int((section_size[1] - im1_size[1]) / 2)
                else:
                    y = im1_cursor + int((section_size[1] - im1_size[1]) / 2)

                # center the image in the section space
                im_black.paste(im1, (x, y), im1)

                # Shift the y-axis cursor at the beginning of next section
                im1_cursor += section_size[1]

            # Check if there is an image for the coloured band
            if os.path.exists(im2_path):

                # Get actual size of image
                im2 = Image.open(im2_path).convert('RGBA')
                im2_size = im2.size

                # Get the size of the section
                section_size = [i for i in self.settings['modules'] if i['position'] == number][0]['config']['size']

                # Calculate coordinates to center the image
                x = int((section_size[0] - im2_size[0]) / 2)

                # If this is the first module, use the y-offset
                if im2_cursor == 0:
                    y = int((section_size[1] - im2_size[1]) / 2)
                else:
                    y = im2_cursor + int((section_size[1] - im2_size[1]) / 2)

                # center the image in the section space
                im_colour.paste(im2, (x, y), im2)

                # Shift the y-axis cursor at the beginning of next section
                im2_cursor += section_size[1]

        # Add info-section if specified --

        # Calculate the max. fontsize for info-section
        if self.settings['info_section']:
            info_height = self.settings["info_section_height"]
            info_width = width
            font = self.font = ImageFont.truetype(
                fonts['NotoSansUI-Regular'], size=14)

            info_x = im_black.size[1] - info_height
            write(im_black, (0, info_x), (info_width, info_height),
                  self.info, font=font)

        # optimize the image by mapping colours to pure black and white
        if self.optimize:
            im_black = self._optimize_im(im_black)
            im_colour = self._optimize_im(im_colour)

        im_black.save(self.image_folder + 'canvas.png', 'PNG')
        im_colour.save(self.image_folder + 'canvas_colour.png', 'PNG')

        # Additionally, combine the two images with color
        def clear_white(img):
            """Replace all white pixels from image with transparent pixels
            """
            x = numpy.asarray(img.convert('RGBA')).copy()
            x[:, :, 3] = (255 * (x[:, :, :3] != 255).any(axis=2)).astype(numpy.uint8)
            return Image.fromarray(x)

        # Additionally, combine the two images with color
        def black_to_colour(img):
            """Replace all black pixels from image with red pixels
            """
            buffer = numpy.array(img.convert('RGB'))
            red, green = buffer[:, :, 0], buffer[:, :, 1]

            threshold = 220

            # non-white -> red
            buffer[numpy.logical_and(red <= threshold, green <= threshold)] = [255, 0, 0]

            return Image.fromarray(buffer)

        # Save full-screen images as well
        im_black = clear_white(im_black)
        im_colour = black_to_colour(im_colour)

        im_colour.paste(im_black, (0, 0), im_black)
        im_colour.save(image_folder + 'full-screen.png', 'PNG')

    @staticmethod
    def _optimize_im(image, threshold=220):
        """Optimize the image for rendering on ePaper displays"""

        buffer = numpy.array(image.convert('RGB'))
        red, green = buffer[:, :, 0], buffer[:, :, 1]

        # grey->black
        buffer[numpy.logical_and(red <= threshold, green <= threshold)] = [0, 0, 0]
        image = Image.fromarray(buffer)
        return image

    def calibrate(self):
        """Calibrate the E-Paper display

        Uses the Display class to calibrate the display with the default of 3
        cycles. After a refresh cycle, a new image is generated and shown.
        """

        self.Display.calibrate()

    def _calibration_check(self):
        """Calibration sheduler
        uses calibration hours from settings file to check if calibration is due"""
        now = arrow.now()
        # print('hour:', now.hour, 'hours:', self._calibration_hours)
        # print('state:', self._calibration_state)
        if now.hour in self._calibration_hours and self._calibration_state == False:
            self.calibrate()
            self._calibration_state = True
        else:
            self._calibration_state = False

    @classmethod
    def add_module(cls, filepath):
        """registers a third party module for inkycal.

        Uses the full filepath of the third party module to check if it is inside
        the correct folder, then checks if it's an inkycal module. Lastly, the
        init files in /inkycal and /inkycal/modules are updated to allow using
        the new module.

        Args:
          - filepath: The full filepath of the third party module. Modules should be
            in Inkycal/inkycal/modules.

        Usage:
          - download a third-party module. The exact link is provided by the
            developer of that module and starts with
            `https://raw.githubusercontent.com/...`

            enter the following in bash to download a module::

              $ cd Inkycal/inkycal/modules #navigate to modules folder in inkycal
              $ wget https://raw.githubusercontent.com/...     #download the module

            then register it with this function::

              >>> from inkycal import Inkycal
              >>> Inkycal.add_module('/full/path/to/the/module/in/inkycal/modules.py')
        """

        module_folder = top_level + '/inkycal/modules'

        if module_folder in filepath:
            filename = filepath.split('.py')[0].split('/')[-1]

            # Extract name of class from given module and validate if it's an inkycal
            # module
            with open(filepath, mode='r') as module:
                module_content = module.read().splitlines()

            for line in module_content:
                if '(inkycal_module):' in line:
                    classname = line.split(' ')[-1].split('(')[0]
                    break

            if not classname:
                raise TypeError("your module doesn't seem to be a correct inkycal module.."
                                "Please check your module again.")

            # Check if filename or classname exists in init of module folder
            with open(module_folder + '/__init__.py', mode='r') as file:
                module_init = file.read().splitlines()

            print('checking module init file..')
            for line in module_init:
                if filename in line:
                    raise Exception(
                        "A module with this filename already exists! \n"
                        "Please consider renaming your module and try again."
                    )
                if classname in line:
                    raise Exception(
                        "A module with this classname already exists! \n"
                        "Please consider renaming your class and try again."
                    )
            print('OK!')

            # Check if filename or classname exists in init of inkycal folder
            with open(top_level + '/inkycal/__init__.py', mode='r') as file:
                inkycal_init = file.read().splitlines()

            print('checking inkycal init file..')
            for line in inkycal_init:
                if filename in line:
                    raise Exception(
                        "A module with this filename already exists! \n"
                        "Please consider renaming your module and try again."
                    )
                if classname in line:
                    raise Exception(
                        "A module with this classname already exists! \n"
                        "Please consider renaming your class and try again."
                    )
            print('OK')

            # If all checks have passed, add the module in the module init file
            with open(module_folder + '/__init__.py', mode='a') as file:
                file.write(f'from .{filename} import {classname} # Added by module adder')

            # If all checks have passed, add the module in the inkycal init file
            with open(top_level + '/inkycal/__init__.py', mode='a') as file:
                file.write(f'import inkycal.modules.{filename} # Added by module adder')

            print(f"Your module '{filename}' with class '{classname}' has been added "
                  "successfully! Hooray!")
            return

        # Check if module is inside the modules folder
        raise Exception(f"Your module should be in {module_folder} "
                        f"but is currently in {filepath}")

    @classmethod
    def remove_module(cls, filename, remove_file=True):
        """unregisters an inkycal module.

        Looks for given filename.py in /modules folder, removes entries of that
        module in init files inside /inkycal and /inkycal/modules

        Args:
          - filename: The filename (with .py ending) of the module which should be
            unregistered. e.g. `'mymodule.py'`
          - remove_file: ->bool (True/False). If set to True, the module is deleted
            after unregistering it, else it remains in the /modules folder


        Usage:
          - Look for the module in Inkycal/inkycal/modules which should be removed.
            Only the filename (with .py) is required, not the full path.

            Use this function to unregister the module from inkycal::

              >>> from inkycal import Inkycal
              >>> Inkycal.remove_module('mymodule.py')
        """

        module_folder = top_level + '/inkycal/modules'

        # Check if module is inside the modules folder and extract classname
        try:
            with open(f"{module_folder}/{filename}", mode='r') as file:
                module_content = file.read().splitlines()

                for line in module_content:
                    if '(inkycal_module):' in line:
                        classname = line.split(' ')[-1].split('(')[0]
                        break

                if not classname:
                    print('The module you are trying to remove is not an inkycal module.. '
                          'Not removing it.')
                    return

        except FileNotFoundError:
            print(f"No module named {filename} found in {module_folder}")
            return

        filename = filename.split('.py')[0]

        # Create a memory backup of /modules init file
        with open(module_folder + '/__init__.py', mode='r') as file:
            module_init = file.read().splitlines()

        print('removing line from module_init')
        # Remove lines that contain classname
        with open(module_folder + '/__init__.py', mode='w') as file:
            for line in module_init:
                if not classname in line:
                    file.write(line + '\n')
                else:
                    print('found, removing')

        # Create a memory backup of inkycal init file
        with open(f"{top_level}/inkycal/__init__.py", mode='r') as file:
            inkycal_init = file.read().splitlines()

        print('removing line from inkycal init')
        # Remove lines that contain classname
        with open(f"{top_level}/inkycal/__init__.py", mode='w') as file:
            for line in inkycal_init:
                if filename in line:
                    print('found, removing')
                else:
                    file.write(line + '\n')

        # remove the file of the third party module if it exists and remove_file
        # was set to True (default)
        if os.path.exists(f"{module_folder}/{filename}.py") and remove_file is True:
            print('deleting module file')
            os.remove(f"{module_folder}/{filename}.py")

        print(f"Your module '{filename}' with class '{classname}' was removed.")


if __name__ == '__main__':
    print(f'running inkycal main in standalone/debug mode')