# Generated by Django 4.2.16 on 2024-09-21 15:44
import os

import pikepdf
from django.conf import settings
from django.db import migrations
from django.db import models
from django.utils.termcolors import colorize as colourise


def source_path(self):
    if self.filename:
        fname = str(self.filename)

    return os.path.join(settings.ORIGINALS_DIR, fname)


def add_number_of_pages_to_pages_count(apps, schema_editor):
    Document = apps.get_model("documents", "Document")

    if not Document.objects.all().exists():
        return

    for doc in Document.objects.filter(mime_type="application/pdf"):
        print(
            "    {} {} {}".format(
                colourise("*", fg="green"),
                colourise("Calculating number of pages for", fg="white"),
                colourise(doc.filename, fg="cyan"),
            ),
        )

        try:
            pdf = pikepdf.open(doc.source_path)

            if pdf.pages is not None:
                doc.pages_count = len(pdf.pages)
                doc.save()
        except Exception as e:  # pragma: no cover
            print(f"Error retrieving number of pages for {doc.filename}: {e}")


def remove_number_of_pages_to_pages_count(apps, schema_editor):
    Document = apps.get_model("documents", "Document")

    if not Document.objects.all().exists():
        return

    for document in Document.objects.filter(mime_type="application/pdf"):
        document.pages_count = 0
        document.save()


class Migration(migrations.Migration):
    dependencies = [
        ("documents", "1052_document_transaction_id"),
    ]

    operations = [
        migrations.AddField(
            model_name="document",
            name="pages_count",
            field=models.PositiveIntegerField(
                blank=False,
                null=True,
                unique=False,
                db_index=False,
            ),
        ),
        migrations.RunPython(
            add_number_of_pages_to_pages_count,
            remove_number_of_pages_to_pages_count,
        ),
    ]