from django.db import models
from django.db.models import Q
from finance.models.base import TimestampedModel


class ImportBatch(TimestampedModel):
    document_hash = models.CharField(max_length=64)
    source_format = models.CharField(max_length=16)
    profile = models.CharField(max_length=32)
    parser_version = models.CharField(max_length=32, default="1")
    encoding = models.CharField(max_length=32)
    context = models.JSONField(default=dict)
    section_mapping = models.JSONField(default=dict)
    summary = models.JSONField(default=dict)
    snapshot = models.JSONField(default=dict)
    actor_kind = models.CharField(max_length=16)
    actor_identifier = models.CharField(max_length=200)
    state = models.CharField(max_length=16, default="PREVIEW")
    revision = models.PositiveIntegerField(default=1)
    result = models.JSONField(default=dict)

    class Meta:
        constraints = [
            models.CheckConstraint(condition=Q(state__in=["PREVIEW", "COMMITTED", "CANCELLED"]), name="import_batch_state"),
            models.CheckConstraint(condition=Q(revision__gte=1), name="import_batch_revision"),
        ]


class ImportItem(TimestampedModel):
    batch = models.ForeignKey(ImportBatch, on_delete=models.PROTECT, related_name="items")
    locator = models.CharField(max_length=255)
    candidate = models.JSONField()
    issues = models.JSONField(default=list)
    duplicates = models.JSONField(default=dict)
    decision = models.JSONField(default=dict)

    class Meta:
        constraints = [models.UniqueConstraint(fields=["batch", "locator"], name="import_item_locator_unique")]