from datetime import date
import os
from django.db import models
from django.forms import ValidationError
from django.utils.translation import gettext as _
from asset.models import Asset, AssetCategory
from base.horilla_company_manager import HorillaCompanyManager

from employee.models import Employee
from django.db.models.signals import post_save, m2m_changed
from django.dispatch import receiver


STATUS = [
    ("requested", "Requested"),
    ("approved", "Approved"),
    ("rejected", "Rejected"),
]
FORMATS = [
    ("any", "Any"),
    ("pdf", "PDF"),
    ("txt", "TXT"),
    ("docx", "DOCX"),
    ("xlsx", "XLSX"),
    ("jpg", "JPG"),
    ("png", "PNG"),
    ("jpeg", "JPEG"),
]


def document_create(instance):
    employees = instance.employee_id.all()
    for employee in employees:
        Document.objects.get_or_create(
            title=f"Upload {instance.title}",
            employee_id=employee,
            document_request_id=instance,
        )


class DocumentRequest(models.Model):
    title = models.CharField(max_length=100)
    employee_id = models.ManyToManyField(Employee)
    format = models.CharField(choices=FORMATS, max_length=10)
    max_size = models.IntegerField(blank=True, null=True)
    description = models.TextField(blank=True, null=True,max_length=255)
    objects = HorillaCompanyManager(related_company_field="employee_id__employee_work_info__company_id")
    is_active = models.BooleanField(default=True)

    def __str__(self):
        return self.title


@receiver(post_save, sender=DocumentRequest)
def doc_request_post_save(sender, instance, **kwargs):
    document_create(instance)


@receiver(m2m_changed, sender=DocumentRequest.employee_id.through)
def your_model_m2m_changed(sender, instance, action, **kwargs):
    if action == "post_add":
        document_create(instance)

    elif action == "post_remove":
        document_create(instance)


class Document(models.Model):
    title = models.CharField(max_length=250)
    employee_id = models.ForeignKey(Employee, on_delete=models.PROTECT)
    document_request_id = models.ForeignKey(
        DocumentRequest, on_delete=models.PROTECT, null=True
    )
    document = models.FileField(upload_to="employee/documents", null=True)
    status = models.CharField(choices=STATUS, max_length=10, default="requested")
    reject_reason = models.TextField(blank=True, null=True,max_length=255)
    is_active = models.BooleanField(default=True)
    expiry_date = models.DateField(null=True,blank=True)
    notify_before = models.IntegerField(default=1,null=True)
    is_digital_asset = models.BooleanField(default=False)
    objects = HorillaCompanyManager(
        related_company_field="employee_id__employee_work_info__company_id"
    )

    def __str__(self) -> str:
        return f"{self.title}"

    def clean(self, *args, **kwargs):
        super().clean(*args, **kwargs)
        file = self.document

        if file and self.document_request_id:
            format = self.document_request_id.format
            max_size = self.document_request_id.max_size
            if max_size:
                if file.size > max_size * 1024 * 1024:
                    raise ValidationError("File size exceeds the limit")

            ext = file.name.split(".")[1].lower()
            if format == "any":
                pass
            elif ext != format:
                raise ValidationError(f"Please upload {format} file only.")

    def save(self, *args, **kwargs):
        if len(self.title) < 3:
            raise ValidationError(_("Title must be at least 3 characters"))
        super().save(*args, **kwargs)
        if self.is_digital_asset:
            asset_category = AssetCategory.objects.get_or_create(
                asset_category_name="Digital Asset"
            )

            Asset.objects.create(
                asset_name=self.title,
                asset_purchase_date=date.today(),
                asset_category_id=asset_category[0],
                asset_status="Not-Available",
                asset_purchase_cost=0,
                expiry_date = self.expiry_date,
                notify_before = self.notify_before,
                asset_tracking_id = f"DIG_ID0{self.pk}",
            )


    def upload_documents_count(self):
        total_requests = Document.objects.filter(
            document_request_id=self.document_request_id
        )
        without_documents = total_requests.filter(document ='').count()
        count = total_requests.count() - without_documents
        return count