from enum import unique
import os, re
from simple_history.models import HistoricalRecords
from django.core.validators import FileExtensionValidator, RegexValidator
from django.core.exceptions import ValidationError
from django.db import models
from django.conf import settings
from versionfield import VersionField



version_pattern = r'\d{1,2}\.\d{1,2}\.\d{1,2}'
version_validator = RegexValidator(regex=version_pattern)
extension_validator = FileExtensionValidator(allowed_extensions=['apk'])

def minimum_version_validator(value, uploaded_version):
    try:
        latest_version = FlutterRelease.objects.latest('version').version
        if (value > latest_version) and (value != uploaded_version):
            raise ValidationError(
            (f'Minimum version ({value}) cannot be less than latest version ({latest_version}) or uploaded version ({uploaded_version})!'),
            params={'value': value},
        )
    except:
        if value != uploaded_version: 
            raise ValidationError(
            (f'Minimum version ({value}) cannot be less than uploaded version ({uploaded_version})!'),
            params={'value': value},
        )
    

def set_apk_filename_with_version(instance, filename):
    name = filename.split('.')[0]
    ext = filename.split('.')[-1]
    version = re.search(version_pattern, filename)
    if not version:
        filename = f'{name}-v{instance.version}.{ext}'
    return os.path.join('./flutter-releases/', filename)

def get_minimum_version():
    try:
        minimum_version = FlutterRelease.objects.latest('version').minimum_version
        return minimum_version
    except:
        return ''


class FlutterRelease(models.Model):
    version = VersionField(unique=True,
                            blank=False, 
                            null=False, 
                            validators=[version_validator]
                            )
    version.help_text='Set version if filename not annotated with version, eg "app-release-v.1.0.1.apk"'
    minimum_version = VersionField(blank=False, null=False,
                                    default=get_minimum_version,
                                    )
    file = models.FileField(null=False, 
                            upload_to=set_apk_filename_with_version, 
                            validators=[extension_validator],
                            )
    update_notes = models.TextField(max_length=1000,
                                    blank=True, 
                                    null=False, 
                                    default=''
                                    )
    release_date = models.DateTimeField(auto_now_add=True)
    history = HistoricalRecords()
    actions = ['delete_selected']
    


    def save(self, *args, **kwargs):
        version = re.search(r'\d+.\d+.\d+', self.file.name)
        if version:
            self.version = version[0]
        minimum_version_validator(self.minimum_version, self.version)
        super(FlutterRelease, self).save(*args, **kwargs)

    def delete(self, *args, **kwargs):
        file = os.path.join(settings.MEDIA_ROOT, self.file.path)
        os.remove(file)
        super(FlutterRelease, self).delete(*args, **kwargs)

    class Meta:
        ordering = ["-version"]


    def __str__(self):
        formatted_datetime = self.release_date.strftime("%d.%m.%Y")
        return f'v.{self.version} from {formatted_datetime}'