#!/usr/bin/python3

from todoist.api import TodoistAPI
from datetime import datetime
import sys
import time
import requests
import argparse
import logging
from datetime import datetime
global overview_item_ids
global overview_item_labels

def main():

    # Version
    current_version = 'v1.2'

    """Main process function."""
    parser = argparse.ArgumentParser()
    parser.add_argument('-a', '--api_key', help='Todoist API Key')
    parser.add_argument(
        '-l', '--label', help='The next action label to use', default='next_action')
    parser.add_argument(
        '-d', '--delay', help='Specify the delay in seconds between syncs', default=5, type=int)
    parser.add_argument(
        '-r', '--recurring', help='Enable re-use of recurring lists', action='store_true')
    parser.add_argument('--debug', help='Enable debugging',
                        action='store_true')
    parser.add_argument('--inbox', help='The method the Inbox project should be processed',
                        default=None, choices=['parallel', 'sequential'])
    parser.add_argument('--parallel_suffix', default='//')
    parser.add_argument('--sequential_suffix', default='--')
    parser.add_argument('--hide_future', help='Hide future dated next actions until the specified number of days',
                        default=7, type=int)
    parser.add_argument(
        '--onetime', help='Update Todoist once and exit', action='store_true')
    parser.add_argument(
        '--nocache', help='Disables caching data to disk for quicker syncing', action='store_true')
    parser.add_argument(
        '-e', '--end', help='Enter a number from 1-24 to define which hour is used as end-of-day time.', type=int)
    args = parser.parse_args()

    # Set debug
    if args.debug:
        log_level = logging.DEBUG
    else:
        log_level = logging.INFO

    logging.basicConfig(level=log_level,
                        format='%(asctime)s %(levelname)-8s %(message)s',
                        datefmt='%Y-%m-%d %H:%M:%S',
                        handlers=[logging.FileHandler(
                            'debug.log', 'w+', 'utf-8'),
                            logging.StreamHandler()]
                        )

    def initialise(args):
        
        # Check we have a API key
        if not args.api_key:
            logging.error("\n\nNo API key set. Run Autodoist with '-a <YOUR_API_KEY>'\n")
            sys.exit(1)

        if args.end < 1 or args.end > 24:
            logging.error("\n\nPlease choose a number from 0 to 24 to indicate which hour is used as alternative end-of-day time.\n")
            sys.exit(1)

        # Run the initial sync
        logging.debug('Connecting to the Todoist API')

        api_arguments = {'token': args.api_key}
        if args.nocache:
            logging.debug('Disabling local caching')
            api_arguments['cache'] = None

        api = TodoistAPI(**api_arguments)
        logging.debug('Syncing the current state from the API')
        api.sync()

        # Check the next action label exists
        labels = api.labels.all(lambda x: x['name'] == args.label)
        if len(labels) > 0:
            label_id = labels[0]['id']
            logging.debug('Label \'%s\' found as label id %d',
                          args.label, label_id)
        else:
            logging.error(
                "\n\nLabel \'%s\' doesn't exist in your Todoist. Please create it or use your custom label by running Autodoist with the argument '-l <YOUR_EXACT_LABEL>'.\n", args.label)
            sys.exit(1)

        logging.info("\nAutodoist has connected and is running fine!\n")

        return api, label_id

    def check_for_update(current_version):
        updateurl = 'https://api.github.com/repos/Hoffelhas/autodoist/releases'

        try:
            r = requests.get(updateurl)
            r.raise_for_status()
            release_info_json = r.json()

            if not current_version == release_info_json[0]['tag_name']:
                logging.warning("\n\nYour version is not up-to-date! \nYour version: {}. Latest version: {}\nSee latest version at: {}\n".format(
                    current_version, release_info_json[0]['tag_name'], release_info_json[0]['html_url']))
                return 1
            else:
                return 0
        except requests.exceptions.ConnectionError as e:
            logging.error(
                "Error while checking for updates (Connection error): {}".format(e))
            return 1
        except requests.exceptions.HTTPError as e:
            logging.error(
                "Error while checking for updates (HTTP error): {}".format(e))
            return 1
        except requests.exceptions.RequestException as e:
            logging.error("Error while checking for updates: {}".format(e))
            return 1

    def get_type(object, key):
        len_suffix = [len(args.parallel_suffix), len(args.sequential_suffix)]

        try:
            old_type = object[key]
        except Exception as e:
            # logging.debug('No defined project_type: %s' % str(e))
            old_type = None

        try:
            name = object['name'].strip()
        except:
            name = object['content'].strip()

        if name == 'Inbox':
            current_type = args.inbox
        elif name[-len_suffix[0]:] == args.parallel_suffix:
            current_type = 'parallel'
        elif name[-len_suffix[1]:] == args.sequential_suffix:
            current_type = 'sequential'
        else:
            current_type = None

        # Check if project type changed with respect to previous run
        if old_type == current_type:
            type_changed = 0
        else:
            type_changed = 1
            object[key] = current_type

        return current_type, type_changed

    def get_project_type(project_object):
        """Identifies how a project should be handled."""
        project_type, project_type_changed = get_type(
            project_object, 'project_type')

        return project_type, project_type_changed

    def get_item_type(item, project_type):
        """Identifies how a item with sub items should be handled."""

        if project_type is None and item['parent_id'] != 0:
            try:
                item_type = item['parent_type']
                item_type_changed = 1
                item['item_type'] = item_type
            except:
                item_type, item_type_changed = get_type(item, 'item_type')
        else:
            item_type, item_type_changed = get_type(item, 'item_type')

        return item_type, item_type_changed

    def add_label(item, label):
        if label not in item['labels']:
            labels = item['labels']
            logging.debug('Updating \'%s\' with label', item['content'])
            labels.append(label)

            try:
                overview_item_ids[str(item['id'])] += 1
            except:
                overview_item_ids[str(item['id'])] = 1
            overview_item_labels[str(item['id'])] = labels

    def remove_label(item, label):
        if label in item['labels']:
            labels = item['labels']
            logging.debug('Removing \'%s\' of its label', item['content'])
            labels.remove(label)

            try:
                overview_item_ids[str(item['id'])] -= 1
            except:
                overview_item_ids[str(item['id'])] = -1
            overview_item_labels[str(item['id'])] = labels

    def update_labels(label_id):
        filtered_overview_ids = [
            k for k, v in overview_item_ids.items() if v != 0]
        for item_id in filtered_overview_ids:
            labels = overview_item_labels[item_id]
            api.items.update(item_id, labels=labels)

    # Check for updates
    check_for_update(current_version)

    # Initialise api
    api, label_id = initialise(args)

    # Main loop
    while True:
        overview_item_ids = {}
        overview_item_labels = {}

        try:
            api.sync()
        except Exception as e:
            logging.exception(
                'Error trying to sync with Todoist API: %s' % str(e))
            quit()

        for project in api.projects.all():

            # Get project type
            project_type, project_type_changed = get_project_type(project)
            logging.debug('Project \'%s\' being processed as %s',
                          project['name'], project_type)

            # Get all items for the project
            items = api.items.all(
                lambda x: x['project_id'] == project['id'])

            # Change top parents_id in order to sort later on
            for item in items:
                if not item['parent_id']:
                    item['parent_id'] = 0

            # Sort by parent_id and filter for completable items
            items = sorted(items, key=lambda x: (
                x['parent_id'], x['child_order']))
            items = list(
                filter(lambda x: not x['content'].startswith('*'), items))

            # If project type has been changed, clean everything for good measure
            if project_type_changed == 1:
                # Remove labels
                [remove_label(item, label_id) for item in items]
                # Remove parent types
                for item in items:
                    item['parent_type'] = None

            # To determine if a sequential task was found
            first_found_project = False
            first_found_item = True

            # For all items in this project
            for item in items:

                # Determine which child_items exist, both all and the ones that have not been checked yet
                non_checked_items = list(
                    filter(lambda x: x['checked'] == 0, items))
                child_items_all = list(
                    filter(lambda x: x['parent_id'] == item['id'], items))
                child_items = list(
                    filter(lambda x: x['parent_id'] == item['id'], non_checked_items))

                # Logic for recurring lists
                if not args.recurring:
                    try:
                        # If old label is present, reset it
                        if item['r_tag'] == 1:
                            item['r_tag'] = 0
                            api.items.update(item['id'])
                    except Exception as e:
                        pass
                # If option turned on, start recurring logic
                else:
                    if item['parent_id'] == 0:
                        try:
                            if item['due']['is_recurring']:
                                try:
                                    # Check if the T0 task date has changed
                                    if item['due']['date'] != item['old_date']:
                                        
                                        # Determine current hour
                                        t = datetime.today()
                                        current_hour = t.hour
                                        
                                        # Check if current time is before our end-of-day
                                        if (args.end - current_hour) > 0:

                                            # Determine the difference in days set by todoist
                                            nd = [int(x) for x in item['due']['date'].split('-')]
                                            od = [int(x) for x in item['old_date'].split('-')]
                                            
                                            new_date = datetime(nd[0], nd[1], nd[2])
                                            old_date = datetime(od[0], od[1], od[2])
                                            today = datetime(t.year, t.month, t.day)
                                            days_difference = (new_date-today).days
                                            days_overdue = (today - old_date).days
                                            
                                            # Only apply if overdue and if it's a daily recurring tasks
                                            if days_overdue >= 1 and days_difference == 1:

                                                # Find curreny date in string format
                                                today_str = [str(x) for x in [today.year, today.month, today.day]]
                                                if len(today_str[1]) == 1:
                                                    today_str[1] = ''.join(['0',today_str[1]])
                                                
                                                # Update due-date to today
                                                item_due = item['due']
                                                item_due['date'] = '-'.join(today_str)
                                                item.update(due=item_due)
                                                # item.update(due={'date': '2020-05-29', 'is_recurring': True, 'string': 'every day'})

                                        # Save the new date for reference us
                                        item.update(old_date=item['due']['date'])

                                        # Mark children for action
                                        for child_item in child_items_all:
                                            child_item['r_tag'] = 1

                                except Exception as e:
                                    # If date has never been saved before, create a new entry
                                    logging.debug(
                                        'New recurring task detected: %s' % str(e))
                                    item['old_date'] = item['due']['date']
                                    api.items.update(item['id'])

                        except Exception as e:
                            logging.debug(
                                'Parent not recurring: %s' % str(e))
                            pass

                    if item['parent_id'] != 0:
                        try:
                            if item['r_tag'] == 1:
                                item.update(checked=0)
                                item.update(in_history=0)
                                item['r_tag'] = 0
                                api.items.update(item['id'])

                                for child_item in child_items_all:
                                    child_item['r_tag'] = 1
                        except Exception as e:
                            logging.debug('Child not recurring: %s' % str(e))
                            pass

                # Skip processing an item if it has already been checked
                if item['checked'] == 1:
                    continue

                # Check item type
                item_type, item_type_changed = get_item_type(
                    item, project_type)
                logging.debug('Identified \'%s\' as %s type',
                              item['content'], item_type)

                # Check the item_type of the project or parent
                if item_type is None:
                    if item['parent_id'] == 0:
                        item_type = project_type
                    else:
                        try:
                            if item['parent_type'] is None:
                                item_type = project_type
                            else:
                                item_type = item['parent_type']
                        except:
                            item_type = project_type
                else:
                    # Reset in case that parentless task is tagged, overrules project
                    first_found_item = False

                # If it is a parentless task
                if item['parent_id'] == 0:
                    if project_type == 'sequential':
                        if not first_found_project:
                            add_label(item, label_id)
                            first_found_project = True
                        elif not first_found_item:
                            add_label(item, label_id)
                            first_found_item = True
                        # else:
                        #     remove_label(item, label_id)
                    elif project_type == 'parallel':
                        add_label(item, label_id)
                    else:
                        # If no project-type has been defined
                        if item_type:
                            add_label(item, label_id)

                # If there are children
                if len(child_items) > 0:
                    # Check if item state has changed, if so clean children for good measure
                    if item_type_changed == 1:
                        [remove_label(child_item, label_id)
                            for child_item in child_items]

                    # Process sequential tagged items (item_type can overrule project_type)
                    if item_type == 'sequential':
                        for child_item in child_items:
                            # Pass item_type down to the children
                            child_item['parent_type'] = item_type
                            # Pass label down to the first child
                            if child_item['checked'] == 0 and label_id in item['labels']:
                                add_label(child_item, label_id)
                                remove_label(item, label_id)
                            else:
                                # Clean for good measure
                                remove_label(child_item, label_id)

                    # Process parallel tagged items or untagged parents
                    elif item_type == 'parallel':
                        remove_label(item, label_id)
                        for child_item in child_items:
                            child_item['parent_type'] = item_type
                            if child_item['checked'] == 0:
                                # child_first_found = True
                                add_label(child_item, label_id)

                    # If item is too far in the future, remove the next_action tag and skip
                    if args.hide_future > 0 and 'due_date_utc' in item.data and item['due_date_utc'] is not None:
                        due_date = datetime.strptime(
                            item['due_date_utc'], '%a %d %b %Y %H:%M:%S +0000')
                        future_diff = (
                            due_date - datetime.utcnow()).total_seconds()
                        if future_diff >= (args.hide_future * 86400):
                            remove_label(item, label_id)
                            continue

        # Commit the queue with changes
        update_labels(label_id)

        if len(api.queue):
            len_api_q = len(api.queue)
            api.commit()
            if len_api_q == 1:    
                logging.info(
                    '%d change committed to Todoist.', len_api_q)
            else:
                logging.info(
                    '%d changes committed to Todoist.', len_api_q)
        else:
            logging.info('No changes in queue, skipping sync.')

        # If onetime is set, exit after first execution.
        if args.onetime:
            break

        logging.debug('Sleeping for %d seconds', args.delay)
        time.sleep(args.delay)


if __name__ == '__main__':
    main()