import datetime
import hashlib
import random
import string
from collections import Counter
from decimal import Decimal
from urllib.parse import urlparse

import pytz
from django import forms
from django.db.models import Q, F
from django.conf import settings
from django.contrib.auth.models import AbstractUser
from django.core.exceptions import ValidationError
from django.db import models
from django.urls import reverse
from django.utils import timezone
from django.utils.functional import cached_property
from reversion import revisions as reversion
from reversion.models import Version
from versioning.versioning import RevisionMixin


def filter_by_pk(filt, query):
    # try and parse an int
    try:
        val = int(query)
        filt = filt | Q(pk=val)
    except:  # noqa
        # not an integer
        pass
    return filt


class Profile(AbstractUser):
    initials = models.CharField(max_length=5, null=True, blank=False)
    phone = models.CharField(max_length=13, blank=True, default='')
    api_key = models.CharField(max_length=40, blank=True, editable=False, default='')
    is_approved = models.BooleanField(default=False, verbose_name="Approval Status", help_text="Designates whether a staff member has approved this user.")
    # Currently only populated by the admin approval email. TODO: Populate it each time we send any email, might need that...
    last_emailed = models.DateTimeField(blank=True, null=True)
    dark_theme = models.BooleanField(default=False)
    is_supervisor = models.BooleanField(default=False)

    reversion_hide = True

    @classmethod
    def make_api_key(cls):
        size = 20
        chars = string.ascii_letters + string.digits
        new_api_key = ''.join(random.choice(chars) for x in range(size))
        return new_api_key

    @property
    def profile_picture(self):
        url = ""
        if settings.USE_GRAVATAR or settings.USE_GRAVATAR is None:
            url = "https://www.gravatar.com/avatar/" + hashlib.md5(
                self.email.encode('utf-8')).hexdigest() + "?d=wavatar&s=500"
        return url

    @property
    def name(self):
        name = self.get_full_name()
        if self.initials:
            name += f' "{self.initials}"'
        return name

    @property
    def latest_events(self):
        return self.event_mic.order_by('-start_date').select_related('person', 'organisation', 'venue', 'mic', 'riskassessment', 'invoice').prefetch_related('checklists')

    @classmethod
    def admins(cls):
        return Profile.objects.filter(email__in=[y for x in settings.ADMINS for y in x])

    @classmethod
    def users_awaiting_approval_count(cls):
        return Profile.objects.filter(models.Q(is_approved=False)).count()

    def __str__(self):
        return self.name

    def current_event(self):
        q = EventCheckIn.objects.filter(person=self, end_time=None)
        return q.latest('time') if q.exists() else None


class ContactableManager(models.Manager):
    def search(self, query=None):
        qs = self.get_queryset()
        if query is not None:
            or_lookup = Q(name__icontains=query) | Q(email__icontains=query) | Q(address__icontains=query) | Q(notes__icontains=query) | Q(
                phone__startswith=query) | Q(phone__endswith=query)

            or_lookup = filter_by_pk(or_lookup, query)

            qs = qs.filter(or_lookup).distinct()  # distinct() is often necessary with Q lookups
        return qs


class Person(models.Model, RevisionMixin):
    name = models.CharField(max_length=50)
    phone = models.CharField(max_length=15, blank=True, default='')
    email = models.EmailField(blank=True, default='')
    address = models.TextField(blank=True, default='')
    notes = models.TextField(blank=True, default='')

    objects = ContactableManager()

    def __str__(self):
        string = self.name
        if self.notes is not None:
            if len(self.notes) > 0:
                string += "*"
        return string

    @property
    def organisations(self):
        o = []
        for e in Event.objects.filter(person=self).select_related('organisation'):
            if e.organisation:
                o.append(e.organisation)

        # Count up occurances and put them in descending order
        c = Counter(o)
        stats = c.most_common()
        return stats

    @property
    def latest_events(self):
        return self.event_set.order_by('-start_date').select_related('person', 'organisation', 'venue', 'mic')

    def get_absolute_url(self):
        return reverse('person_detail', kwargs={'pk': self.pk})


class Organisation(models.Model, RevisionMixin):
    name = models.CharField(max_length=50)
    phone = models.CharField(max_length=15, blank=True, default='')
    email = models.EmailField(blank=True, default='')
    address = models.TextField(blank=True, default='')
    notes = models.TextField(blank=True, default='')
    union_account = models.BooleanField(default=False)

    objects = ContactableManager()

    def __str__(self):
        string = self.name
        if self.notes is not None:
            if len(self.notes) > 0:
                string += "*"
        return string

    @property
    def persons(self):
        p = []
        for e in Event.objects.filter(organisation=self).select_related('person'):
            if e.person:
                p.append(e.person)

        # Count up occurances and put them in descending order
        c = Counter(p)
        stats = c.most_common()
        return stats

    @property
    def latest_events(self):
        return self.event_set.order_by('-start_date').select_related('person', 'organisation', 'venue', 'mic')

    def get_absolute_url(self):
        return reverse('organisation_detail', kwargs={'pk': self.pk})


class VatManager(models.Manager):
    def current_rate(self):
        return self.find_rate(timezone.now())

    def find_rate(self, date):
        try:
            return self.filter(start_at__lte=date).latest()
        except VatRate.DoesNotExist:
            r = VatRate
            r.rate = 0
            return r


@reversion.register
class VatRate(models.Model, RevisionMixin):
    start_at = models.DateField()
    rate = models.DecimalField(max_digits=6, decimal_places=6)
    comment = models.CharField(max_length=255)

    objects = VatManager()

    reversion_hide = True

    @property
    def as_percent(self):
        return self.rate * 100

    class Meta:
        ordering = ['-start_at']
        get_latest_by = 'start_at'

    def __str__(self):
        return f"{self.comment} {self.start_at} @ {self.as_percent}%"


class Venue(models.Model, RevisionMixin):
    name = models.CharField(max_length=255)
    phone = models.CharField(max_length=15, blank=True, default='')
    email = models.EmailField(blank=True, default='')
    three_phase_available = models.BooleanField(default=False)
    notes = models.TextField(blank=True, default='')
    address = models.TextField(blank=True, default='')

    objects = ContactableManager()

    def __str__(self):
        string = self.name
        if self.notes and len(self.notes) > 0:
            string += "*"
        return string

    @property
    def latest_events(self):
        return self.event_set.order_by('-start_date').select_related('person', 'organisation', 'venue', 'mic')

    def get_absolute_url(self):
        return reverse('venue_detail', kwargs={'pk': self.pk})


class EventManager(models.Manager):
    def current_events(self):
        events = self.filter(
            (models.Q(start_date__gte=timezone.now(), end_date__isnull=True, dry_hire=False) & ~models.Q(
                status=Event.CANCELLED)) |  # Starts after with no end
            (models.Q(end_date__gte=timezone.now().date(), dry_hire=False) & ~models.Q(
                status=Event.CANCELLED)) |  # Ends after
            (models.Q(dry_hire=True, start_date__gte=timezone.now()) & ~models.Q(
                status=Event.CANCELLED)) |  # Active dry hire
            (models.Q(dry_hire=True, checked_in_by__isnull=True) & (
                models.Q(status=Event.BOOKED) | models.Q(status=Event.CONFIRMED))) |  # Active dry hire GT
            models.Q(status=Event.CANCELLED, start_date__gte=timezone.now())  # Canceled but not started
        ).order_by('start_date', 'end_date', 'start_time', 'end_time', 'meet_at').select_related('person', 'organisation', 'venue', 'mic')

        return events

    def events_in_bounds(self, start, end):
        events = self.filter(
            (models.Q(start_date__gte=start.date(), start_date__lte=end.date())) |  # Start date in bounds
            (models.Q(end_date__gte=start.date(), end_date__lte=end.date())) |  # End date in bounds
            (models.Q(access_at__gte=start, access_at__lte=end)) |  # Access at in bounds
            (models.Q(meet_at__gte=start, meet_at__lte=end)) |  # Meet at in bounds

            (models.Q(start_date__lte=start, end_date__gte=end)) |  # Start before, end after
            (models.Q(access_at__lte=start, start_date__gte=end)) |  # Access before, start after
            (models.Q(access_at__lte=start, end_date__gte=end)) |  # Access before, end after
            (models.Q(meet_at__lte=start, start_date__gte=end)) |  # Meet before, start after
            (models.Q(meet_at__lte=start, end_date__gte=end))  # Meet before, end after

        ).order_by('start_date', 'end_date', 'start_time', 'end_time', 'meet_at').select_related('person',
                                                                                                 'organisation',
                                                                                                 'venue', 'mic')
        return events

    def rig_count(self):
        event_count = self.filter(
            (models.Q(start_date__gte=timezone.now(), end_date__isnull=True, dry_hire=False,
                      is_rig=True) & ~models.Q(
                status=Event.CANCELLED)) |  # Starts after with no end
            (models.Q(end_date__gte=timezone.now(), dry_hire=False, is_rig=True) & ~models.Q(
                status=Event.CANCELLED)) |  # Ends after
            (models.Q(dry_hire=True, start_date__gte=timezone.now(), is_rig=True) & ~models.Q(
                status=Event.CANCELLED))  # Active dry hire
        ).count()
        return event_count

    def waiting_invoices(self):
        events = self.filter(
            (
                models.Q(start_date__lte=datetime.date.today(), end_date__isnull=True) |  # Starts before with no end
                models.Q(end_date__lte=datetime.date.today())  # Or has end date, finishes before
            ) & models.Q(invoice__isnull=True) &  # Has not already been invoiced
            models.Q(is_rig=True)  # Is a rig (not non-rig)
        ).order_by('start_date') \
            .select_related('person', 'organisation', 'venue', 'mic') \
            .prefetch_related('items')

        return events

    def search(self, query=None):
        qs = self.get_queryset()
        if query is not None:
            or_lookup = Q(name__icontains=query) | Q(description__icontains=query) | Q(notes__icontains=query)

            or_lookup = filter_by_pk(or_lookup, query)

            try:
                if query[0] == "N":
                    val = int(query[1:])
                    or_lookup = Q(pk=val)  # If string is N###### then do a simple PK filter
            except:  # noqa
                pass

            qs = qs.filter(or_lookup).distinct()  # distinct() is often necessary with Q lookups
        return qs


def validate_forum_url(value):
    if not value:
        return  # Required error is done the field
    obj = urlparse(value)
    if obj.hostname not in ('forum.nottinghamtec.co.uk'):
        raise ValidationError('URL must point to a location on the TEC Forum')


@reversion.register(follow=['items'])
class Event(models.Model, RevisionMixin):
    # Done to make it much nicer on the database
    PROVISIONAL = 0
    CONFIRMED = 1
    BOOKED = 2
    CANCELLED = 3
    EVENT_STATUS_CHOICES = (
        (PROVISIONAL, 'Provisional'),
        (CONFIRMED, 'Confirmed'),
        (BOOKED, 'Booked'),
        (CANCELLED, 'Cancelled'),
    )

    name = models.CharField(max_length=255)
    person = models.ForeignKey('Person', null=True, blank=True, on_delete=models.CASCADE)
    organisation = models.ForeignKey('Organisation', blank=True, null=True, on_delete=models.CASCADE)
    venue = models.ForeignKey('Venue', blank=True, null=True, on_delete=models.CASCADE)
    description = models.TextField(blank=True, default='')
    notes = models.TextField(blank=True, default='')
    status = models.IntegerField(choices=EVENT_STATUS_CHOICES, default=PROVISIONAL)
    dry_hire = models.BooleanField(default=False)
    is_rig = models.BooleanField(default=True)
    based_on = models.ForeignKey('Event', on_delete=models.SET_NULL, related_name='future_events', blank=True,
                                 null=True)

    # Timing
    start_date = models.DateField()
    start_time = models.TimeField(blank=True, null=True)
    end_date = models.DateField(blank=True, null=True)
    end_time = models.TimeField(blank=True, null=True)
    access_at = models.DateTimeField(blank=True, null=True)
    meet_at = models.DateTimeField(blank=True, null=True)

    # Crew management
    checked_in_by = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='event_checked_in', blank=True, null=True,
                                      on_delete=models.CASCADE)
    mic = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='event_mic', blank=True, null=True,
                            verbose_name="MIC", on_delete=models.CASCADE)

    # Monies
    purchase_order = models.CharField(max_length=255, blank=True, default='', verbose_name='PO')
    collector = models.CharField(max_length=255, blank=True, default='', verbose_name='collected by')

    # Authorisation request details
    auth_request_by = models.ForeignKey('Profile', null=True, blank=True, on_delete=models.CASCADE)
    auth_request_at = models.DateTimeField(null=True, blank=True)
    auth_request_to = models.EmailField(blank=True, default='')

    forum_url = models.URLField(default='', blank=True, validators=[validate_forum_url])

    @property
    def display_id(self):
        if self.pk:
            if self.is_rig:
                return f"N{self.pk:05d}"
            return self.pk
        return "????"

    # Calculated values
    """
    EX Vat
    """

    @property
    def sum_total(self):
        total = self.items.aggregate(
            sum_total=models.Sum(models.F('cost') * models.F('quantity'),
                                 output_field=models.DecimalField(max_digits=10, decimal_places=2))
        )['sum_total']
        if total:
            return total
        return Decimal("0.00")

    @cached_property
    def vat_rate(self):
        return VatRate.objects.find_rate(self.start_date)

    @property
    def vat(self):
        # No VAT is owed on internal transfers
        if self.internal:
            return 0
        return Decimal(self.sum_total * self.vat_rate.rate).quantize(Decimal('.01'))

    """
    Inc VAT
    """

    @property
    def total(self):
        return Decimal(self.sum_total + self.vat).quantize(Decimal('.01'))

    @property
    def cancelled(self):
        return (self.status == self.CANCELLED)

    @property
    def confirmed(self):
        return (self.status == self.BOOKED or self.status == self.CONFIRMED)

    @property
    def hs_done(self):
        return self.riskassessment is not None and self.has_checklist and self.has_power

    @property
    def has_checklist(self):
        return self.checklists.exists()

    @property
    def has_power(self):
        return self.power_tests.exists()

    @property
    def has_start_time(self):
        return self.start_time is not None

    @property
    def has_end_time(self):
        return self.end_time is not None

    @property
    def earliest_time(self):
        """Finds the earliest time defined in the event - this function could return either a tzaware datetime, or a naiive date object"""

        # Put all the datetimes in a list
        datetime_list = []

        if self.access_at:
            datetime_list.append(self.access_at)

        if self.meet_at:
            datetime_list.append(self.meet_at)

        # If there is no start time defined, pretend it's midnight
        startTimeFaked = False
        if self.has_start_time:
            startDateTime = datetime.datetime.combine(self.start_date, self.start_time)
        else:
            startDateTime = datetime.datetime.combine(self.start_date, datetime.time(00, 00))
            startTimeFaked = True

        # timezoneIssues - apply the default timezone to the naiive datetime
        tz = pytz.timezone(settings.TIME_ZONE)
        startDateTime = tz.localize(startDateTime)
        datetime_list.append(startDateTime)  # then add it to the list

        earliest = min(datetime_list).astimezone(tz)  # find the earliest datetime in the list

        # if we faked it & it's the earliest, better own up
        if startTimeFaked and earliest == startDateTime:
            return self.start_date

        return earliest

    @property
    def latest_time(self):
        """Returns the end of the event - this function could return either a tzaware datetime, or a naiive date object"""
        tz = pytz.timezone(settings.TIME_ZONE)
        endDate = self.end_date
        if endDate is None:
            endDate = self.start_date

        if self.has_end_time:
            endDateTime = datetime.datetime.combine(endDate, self.end_time)
            tz = pytz.timezone(settings.TIME_ZONE)
            endDateTime = tz.localize(endDateTime)

            return endDateTime

        else:
            return endDate

    @property
    def internal(self):
        return bool(self.organisation and self.organisation.union_account)

    @property
    def authorised(self):
        if self.internal:
            return self.authorisation.amount == self.total
        else:
            return bool(self.purchase_order)

    @property
    def can_check_in(self):
        earliest = self.earliest_time
        if isinstance(self.earliest_time, datetime.date):
            earliest = datetime.datetime.combine(self.start_date, datetime.time(00, 00))
            tz = pytz.timezone(settings.TIME_ZONE)
            earliest = tz.localize(earliest)
        return not self.dry_hire and not self.status == Event.CANCELLED and earliest <= timezone.now()

    objects = EventManager()

    def get_absolute_url(self):
        return reverse('event_detail', kwargs={'pk': self.pk})

    def __str__(self):
        return f"{self.display_id} | {self.name}"

    def clean(self):
        errdict = {}
        if self.end_date and self.start_date > self.end_date:
            errdict['end_date'] = ['Unless you\'ve invented time travel, the event can\'t finish before it has started.']

        startEndSameDay = not self.end_date or self.end_date == self.start_date
        hasStartAndEnd = self.has_start_time and self.has_end_time
        if startEndSameDay and hasStartAndEnd and self.start_time > self.end_time:
            errdict['end_time'] = ['Unless you\'ve invented time travel, the event can\'t finish before it has started.']

        if self.access_at is not None:
            if self.access_at.date() > self.start_date:
                errdict['access_at'] = ['Regardless of what some clients might think, access time cannot be after the event has started.']
            elif self.start_time is not None and self.start_date == self.access_at.date() and self.access_at.time() > self.start_time:
                errdict['access_at'] = ['Regardless of what some clients might think, access time cannot be after the event has started.']

        if errdict != {}:  # If there was an error when validation
            raise ValidationError(errdict)

    def save(self, *args, **kwargs):
        """Call :meth:`full_clean` before saving."""
        self.full_clean()
        super(Event, self).save(*args, **kwargs)


@reversion.register
class EventItem(models.Model, RevisionMixin):
    event = models.ForeignKey('Event', related_name='items', blank=True, on_delete=models.CASCADE)
    name = models.CharField(max_length=255)
    description = models.TextField(blank=True, default='')
    quantity = models.IntegerField()
    cost = models.DecimalField(max_digits=10, decimal_places=2)
    order = models.IntegerField()

    reversion_hide = True

    @property
    def total_cost(self):
        return self.cost * self.quantity

    class Meta:
        ordering = ['order']

    def __str__(self):
        return f"{self.event_id}.{self.order}: {self.event.name} | {self.name}"

    @property
    def activity_feed_string(self):
        return f"item {self.name}"


@reversion.register
class EventAuthorisation(models.Model, RevisionMixin):
    event = models.OneToOneField('Event', related_name='authorisation', on_delete=models.CASCADE)
    email = models.EmailField()
    name = models.CharField(max_length=255)
    uni_id = models.CharField(max_length=10, blank=True, default='', verbose_name="University ID")
    account_code = models.CharField(max_length=50, default='', blank=True)
    amount = models.DecimalField(max_digits=10, decimal_places=2, verbose_name="authorisation amount")
    sent_by = models.ForeignKey('Profile', on_delete=models.CASCADE)

    def get_absolute_url(self):
        return reverse('event_detail', kwargs={'pk': self.event_id})

    @property
    def activity_feed_string(self):
        return f"{self.event.display_id} (requested by {self.sent_by.initials})"


class InvoiceManager(models.Manager):
    def outstanding_invoices(self):
        # Manual query is the only way I have found to do this efficiently. Not ideal but needs must
        sql = "SELECT * FROM " \
              "(SELECT " \
              "(SELECT COUNT(p.amount) FROM \"RIGS_payment\" AS p WHERE p.invoice_id=\"RIGS_invoice\".id) AS \"payment_count\", " \
              "(SELECT SUM(ei.cost * ei.quantity) FROM \"RIGS_eventitem\" AS ei WHERE ei.event_id=\"RIGS_invoice\".event_id) AS \"cost\", " \
              "(SELECT SUM(p.amount) FROM \"RIGS_payment\" AS p WHERE p.invoice_id=\"RIGS_invoice\".id) AS \"payments\", " \
              "\"RIGS_invoice\".\"id\", \"RIGS_invoice\".\"event_id\", \"RIGS_invoice\".\"invoice_date\", \"RIGS_invoice\".\"void\" FROM \"RIGS_invoice\") " \
              "AS sub " \
              "WHERE (((cost > 0.0) AND (payment_count=0)) OR (cost - payments) <> 0.0) AND void = '0'" \
              "ORDER BY invoice_date"

        query = self.raw(sql)
        return query

    def search(self, query=None):
        qs = self.get_queryset()
        if query is not None:
            or_lookup = Q(event__name__icontains=query)

            or_lookup = filter_by_pk(or_lookup, query)

            # try and parse an int
            try:
                val = int(query)
                or_lookup = or_lookup | Q(event__pk=val)
            except:  # noqa
                # not an integer
                pass

            try:
                if query[0] == "N":
                    val = int(query[1:])
                    or_lookup = Q(event__pk=val)  # If string is Nxxxxx then filter by event number
                elif query[0] == "#":
                    val = int(query[1:])
                    or_lookup = Q(pk=val)  # If string is #xxxxx then filter by invoice number
            except:  # noqa
                pass

            qs = qs.filter(or_lookup).distinct()  # distinct() is often necessary with Q lookups
        return qs


@reversion.register(follow=['payment_set'])
class Invoice(models.Model, RevisionMixin):
    event = models.OneToOneField('Event', on_delete=models.CASCADE)
    invoice_date = models.DateField(auto_now_add=True)
    void = models.BooleanField(default=False)

    reversion_perm = 'RIGS.view_invoice'

    objects = InvoiceManager()

    @property
    def sum_total(self):
        return self.event.sum_total

    @property
    def total(self):
        return self.event.total

    @property
    def payment_total(self):
        total = self.payment_set.aggregate(total=models.Sum('amount'))['total']
        if total:
            return total
        return Decimal("0.00")

    @property
    def balance(self):
        return self.sum_total - self.payment_total

    @property
    def is_closed(self):
        return self.balance == 0 or self.void

    def get_absolute_url(self):
        return reverse('invoice_detail', kwargs={'pk': self.pk})

    @property
    def activity_feed_string(self):
        return f"{self.display_id} for Event {self.event.display_id}"

    def __str__(self):
        return f"{self.display_id}: {self.event} (£{self.balance:.2f})"

    @property
    def display_id(self):
        return f"#{self.pk:05d}"

    class Meta:
        ordering = ['-invoice_date']


@reversion.register
class Payment(models.Model, RevisionMixin):
    CASH = 'C'
    INTERNAL = 'I'
    EXTERNAL = 'E'
    SUCORE = 'SU'
    ADJUSTMENT = 'T'
    METHODS = (
        (CASH, 'Cash'),
        (INTERNAL, 'Internal'),
        (EXTERNAL, 'External'),
        (SUCORE, 'SU Core'),
        (ADJUSTMENT, 'TEC Adjustment'),
    )

    invoice = models.ForeignKey('Invoice', on_delete=models.CASCADE)
    date = models.DateField()
    amount = models.DecimalField(max_digits=10, decimal_places=2, help_text='Please use ex. VAT')
    method = models.CharField(max_length=2, choices=METHODS, default='', blank=True)

    reversion_hide = True

    def __str__(self):
        return f"{self.get_method_display()}: {self.amount}"

    @property
    def activity_feed_string(self):
        return f"payment of £{self.amount}"


def validate_url(value):
    if not value:
        return  # Required error is done the field
    obj = urlparse(value)
    if obj.hostname not in ('nottinghamtec.sharepoint.com'):
        raise ValidationError('URL must point to a location on the TEC Sharepoint')


class ReviewableModel(models.Model):
    reviewed_at = models.DateTimeField(null=True, blank=True)
    reviewed_by = models.ForeignKey(settings.AUTH_USER_MODEL, blank=True, null=True,
                                    verbose_name="Reviewer", on_delete=models.CASCADE)

    class Meta:
        abstract = True

    @cached_property
    def fieldz(self):
        return [n.name for n in list(self._meta.get_fields()) if n.name != 'reviewed_at' and n.name != 'reviewed_by' and not n.is_relation and not n.auto_created]


@reversion.register
class RiskAssessment(ReviewableModel, RevisionMixin):
    SMALL = (0, 'Small')
    MEDIUM = (1, 'Medium')
    LARGE = (2, 'Large')
    SIZES = (SMALL, MEDIUM, LARGE)

    event = models.OneToOneField('Event', on_delete=models.CASCADE)
    # General
    nonstandard_equipment = models.BooleanField(help_text="Does the event require any hired in equipment or use of equipment that is not covered by <a href='https://nottinghamtec.sharepoint.com/:f:/g/HealthAndSafety/Eo4xED_DrqFFsfYIjKzMZIIB6Gm_ZfR-a8l84RnzxtBjrA?e=Bf0Haw'>"
                                                          "TEC's standard risk assessments and method statements?</a>")
    nonstandard_use = models.BooleanField(help_text="Are TEC using their equipment in a way that is abnormal?<br><small>i.e. Not covered by TECs standard health and safety documentation</small>")
    contractors = models.BooleanField(help_text="Are you using any external contractors?<br><small>i.e. Freelancers/Crewing Companies</small>")
    other_companies = models.BooleanField(help_text="Are TEC working with any other companies on site?<br><small>e.g. TEC is providing the lighting while another company does sound</small>")
    crew_fatigue = models.BooleanField(help_text="Is crew fatigue likely to be a risk at any point during this event?")
    general_notes = models.TextField(blank=True, default='', help_text="Did you have to consult a supervisor about any of the above? If so who did you consult and what was the outcome?")

    # Power
    big_power = models.BooleanField(help_text="Does the event require larger power supplies than 13A or 16A single phase wall sockets, or draw more than 20A total current?")
    power_mic = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='power_mic', blank=True, null=True,
                                  verbose_name="Power MIC", on_delete=models.CASCADE, help_text="Who is the Power MIC? (if yes to the above question, this person <em>must</em> be a Power Technician or Power Supervisor)")
    outside = models.BooleanField(help_text="Is the event outdoors?")
    generators = models.BooleanField(help_text="Will generators be used?")
    other_companies_power = models.BooleanField(help_text="Will TEC be supplying power to any other companies?")
    nonstandard_equipment_power = models.BooleanField(help_text="Does the power plan require the use of any power equipment (distros, dimmers, motor controllers, etc.) that does not belong to TEC?")
    multiple_electrical_environments = models.BooleanField(help_text="Will the electrical installation occupy more than one electrical environment?")
    power_notes = models.TextField(blank=True, default='', help_text="Did you have to consult a supervisor about any of the above? If so who did you consult and what was the outcome?")
    power_plan = models.URLField(blank=True, default='', help_text="Upload your power plan to the <a href='https://nottinghamtec.sharepoint.com/'>Sharepoint</a> and submit a link", validators=[validate_url])

    # Sound
    noise_monitoring = models.BooleanField(help_text="Does the event require noise monitoring or any non-standard procedures in order to comply with health and safety legislation or site rules?")
    sound_notes = models.TextField(blank=True, default='', help_text="Did you have to consult a supervisor about any of the above? If so who did you consult and what was the outcome?")

    # Site
    known_venue = models.BooleanField(help_text="Is this venue new to you (the MIC) or new to TEC?")
    safe_loading = models.BooleanField(help_text="Are there any issues preventing a safe load in or out? (e.g. sufficient lighting, flat, not in a crowded area etc.)")
    safe_storage = models.BooleanField(help_text="Are there any problems with safe and secure equipment storage?")
    area_outside_of_control = models.BooleanField(help_text="Is any part of the work area out of TEC's direct control or openly accessible during the build or breakdown period?")
    barrier_required = models.BooleanField(help_text="Is there a requirement for TEC to provide any barrier for security or protection of persons/equipment?")
    nonstandard_emergency_procedure = models.BooleanField(help_text="Does the emergency procedure for the event differ from TEC's standard procedures?")

    # Structures
    special_structures = models.BooleanField(help_text="Does the event require use of winch stands, motors, MPT Towers, or staging?")
    suspended_structures = models.BooleanField(help_text="Are any structures (excluding projector screens and IWBs) being suspended from TEC's structures?")
    persons_responsible_structures = models.TextField(blank=True, default='', help_text="Who are the persons on site responsible for their use?")
    rigging_plan = models.URLField(blank=True, default='', help_text="Upload your rigging plan to the <a href='https://nottinghamtec.sharepoint.com/'>Sharepoint</a> and submit a link", validators=[validate_url])

    # Blimey that was a lot of options

    supervisor_consulted = models.BooleanField(null=True)

    expected_values = {
        'nonstandard_equipment': False,
        'nonstandard_use': False,
        'contractors': False,
        'other_companies': False,
        'crew_fatigue': False,
        # 'big_power': False Doesn't require checking with a super either way
        'generators': False,
        'other_companies_power': False,
        'nonstandard_equipment_power': False,
        'multiple_electrical_environments': False,
        'noise_monitoring': False,
        'known_venue': False,
        'safe_loading': False,
        'safe_storage': False,
        'area_outside_of_control': False,
        'barrier_required': False,
        'nonstandard_emergency_procedure': False,
        'special_structures': False,
        'suspended_structures': False,
    }
    inverted_fields = {key: value for (key, value) in expected_values.items() if not value}.keys()

    def clean(self):
        # Check for idiots
        if not self.outside and self.generators:
            raise forms.ValidationError("Engage brain, please. <strong>No generators indoors!(!)</strong>")

    class Meta:
        ordering = ['event']
        permissions = [
            ('review_riskassessment', 'Can review Risk Assessments')
        ]

    @property
    def event_size(self):
        # Confirm event size. Check all except generators, since generators entails outside
        if self.outside or self.other_companies_power or self.nonstandard_equipment_power or self.multiple_electrical_environments:
            return self.LARGE[0]
        elif self.big_power:
            return self.MEDIUM[0]
        else:
            return self.SMALL[0]

    def get_event_size_display(self):
        return self.SIZES[self.event_size][1] + " Event"

    def __str__(self):
        return f"{self.pk} | {self.event}"

    def get_absolute_url(self):
        return reverse('ra_detail', kwargs={'pk': self.pk})

    @property
    def activity_feed_string(self):
        return str(self.event)

    @property
    def name(self):
        return str(self)


@reversion.register
class EventChecklist(ReviewableModel, RevisionMixin):
    event = models.ForeignKey('Event', related_name='checklists', on_delete=models.CASCADE)

    # General
    venue = models.ForeignKey('Venue', on_delete=models.CASCADE)
    date = models.DateField()

    # Safety Checks
    safe_parking = models.BooleanField(blank=True, null=True, help_text="Vehicles parked safely?<br><small>(does not obstruct venue access)</small>")
    safe_packing = models.BooleanField(blank=True, null=True, help_text="Equipment packed away safely?<br><small>(including flightcases)</small>")
    exits = models.BooleanField(blank=True, null=True, help_text="Emergency exits clear?")
    trip_hazard = models.BooleanField(blank=True, null=True, help_text="Appropriate barriers around kit and cabling secured?")
    warning_signs = models.BooleanField(blank=True, help_text="Warning signs in place?<br><small>(strobe, smoke, power etc.)</small>")
    ear_plugs = models.BooleanField(blank=True, null=True, help_text="Ear plugs issued to crew where needed?")
    hs_location = models.CharField(blank=True, default='', max_length=255, help_text="Location of Safety Bag/Box")
    extinguishers_location = models.CharField(blank=True, default='', max_length=255, help_text="Location of fire extinguishers")

    inverted_fields = []

    class Meta:
        ordering = ['event']
        permissions = [
            ('review_eventchecklist', 'Can review Event Checklists')
        ]

    def __str__(self):
        return f"{self.pk} - {self.event}"

    @property
    def activity_feed_string(self):
        return str(self.event)

    def get_absolute_url(self):
        return reverse('ec_detail', kwargs={'pk': self.pk})


@reversion.register
class PowerTestRecord(ReviewableModel, RevisionMixin):
    earth_fault_text = "Earth Fault Loop Impedance (Z<small>S</small>) / Ω"
    pssc_text = "Prospective Short Circuit Current / A"

    event = models.ForeignKey('Event', related_name='power_tests', on_delete=models.CASCADE)
    power_mic = models.ForeignKey(settings.AUTH_USER_MODEL, blank=True, null=True, related_name='checklists',
                                  verbose_name="Power MIC", on_delete=models.CASCADE, help_text="Who is the Power MIC?")
    venue = models.ForeignKey('Venue', on_delete=models.CASCADE)
    notes = models.TextField(blank=True, default='')
    # Small Electrical Checks
    rcds = models.BooleanField(blank=True, null=True, help_text="RCDs installed where needed and tested?")
    supply_test = models.BooleanField(blank=True, null=True, help_text="Electrical supplies tested?<br><small>(using socket tester)</small>")

    # Shared electrical checks
    earthing = models.BooleanField(blank=True, null=True, help_text="Equipment appropriately earthed?<br><small>(truss, stage, generators etc)</small>")
    pat = models.BooleanField(blank=True, null=True, help_text="All equipment in PAT period?")

    # Medium Electrical Checks
    source_rcd = models.BooleanField(blank=True, null=True, help_text="Source RCD protected?<br><small>(if cable is more than 3m long) </small>")
    labelling = models.BooleanField(blank=True, null=True, help_text="Appropriate and clear labelling on distribution and cabling?")
    # First Distro
    fd_voltage_l1 = models.IntegerField(blank=True, null=True, verbose_name="First Distro Voltage L1-N", help_text="L1 - N")
    fd_voltage_l2 = models.IntegerField(blank=True, null=True, verbose_name="First Distro Voltage L2-N", help_text="L2 - N")
    fd_voltage_l3 = models.IntegerField(blank=True, null=True, verbose_name="First Distro Voltage L3-N", help_text="L3 - N")
    fd_phase_rotation = models.BooleanField(blank=True, null=True, verbose_name="Phase Rotation", help_text="Phase Rotation<br><small>(if required)</small>")
    fd_earth_fault = models.DecimalField(blank=True, null=True, max_digits=6, decimal_places=2, verbose_name="Earth Fault Loop Impedance", help_text=earth_fault_text)
    fd_pssc = models.IntegerField(blank=True, null=True, verbose_name="PSCC", help_text=pssc_text)
    # Worst case points
    w1_description = models.CharField(blank=True, default='', max_length=255, help_text="Description")
    w1_polarity = models.BooleanField(blank=True, null=True, help_text="Polarity Checked?")
    w1_voltage = models.IntegerField(blank=True, null=True, help_text="Voltage / V")
    w1_earth_fault = models.DecimalField(blank=True, null=True, max_digits=6, decimal_places=2, verbose_name="Earth Fault Loop Impedance", help_text=earth_fault_text)
    w2_description = models.CharField(blank=True, default='', max_length=255, help_text="Description")
    w2_polarity = models.BooleanField(blank=True, null=True, help_text="Polarity Checked?")
    w2_voltage = models.IntegerField(blank=True, null=True, help_text="Voltage / V")
    w2_earth_fault = models.DecimalField(blank=True, null=True, max_digits=6, decimal_places=2, verbose_name="Earth Fault Loop Impedance", help_text=earth_fault_text)
    w3_description = models.CharField(blank=True, default='', max_length=255, help_text="Description")
    w3_polarity = models.BooleanField(blank=True, null=True, help_text="Polarity Checked?")
    w3_voltage = models.IntegerField(blank=True, null=True, help_text="Voltage / V")
    w3_earth_fault = models.DecimalField(blank=True, null=True, max_digits=6, decimal_places=2, verbose_name="Earth Fault Loop Impedance", help_text=earth_fault_text)

    all_rcds_tested = models.BooleanField(blank=True, null=True, help_text="All circuit RCDs tested?<br><small>(using test button)</small>")
    public_sockets_tested = models.BooleanField(blank=True, null=True, help_text="Public/Performer accessible circuits tested?<br><small>(using socket tester)</small>")

    class Meta:
        ordering = ['event']
        permissions = [
            ('review_power', 'Can review Power Test Records')
        ]

    def __str__(self):
        return f"{self.pk} - {self.event}"

    def get_absolute_url(self):
        return reverse('pt_detail', kwargs={'pk': self.pk})

    @property
    def activity_feed_string(self):
        return str(self.event)


class EventCheckIn(models.Model):
    event = models.ForeignKey('Event', related_name='crew', on_delete=models.CASCADE)
    person = models.ForeignKey(settings.AUTH_USER_MODEL, related_name='checkins', on_delete=models.CASCADE)
    time = models.DateTimeField()
    role = models.CharField(max_length=50, blank=True)
    vehicle = models.CharField(max_length=100, blank=True)
    end_time = models.DateTimeField(null=True, blank=True)

    def __str__(self):
        return f"{self.person} on {self.event}"

    def clean(self):
        sass = " Please invent time travel and retry."
        if self.time > timezone.now():
            raise ValidationError("May not check in in the future." + sass)
        if self.end_time and self.end_time < self.time:
            raise ValidationError("May not check out before you've checked in." + sass)

    def get_absolute_url(self):
        return reverse('event_detail', kwargs={'pk': self.event_id})

    def active(self):
        return end_time is not None