"""
CMS Integration — API requests/responses, payments, recoupment.
"""

import uuid

from django.conf import settings
from django.db import models
from django.utils.translation import gettext_lazy as _

# Patient-level FHIR keys redacted from stored CMS payloads when
# ALLOW_SYNTHETIC_MBI is disabled. The wire payload sent to CMS is untouched —
# only what we persist in audit rows is scrubbed. Identifiers (incl. MBI) are
# kept so submissions stay traceable. Scrubbing applies inside Patient
# resources only: FHIR Parameters use "name" for parameter labels, which must
# survive intact.
_PHI_PATIENT_KEYS = ("name", "birthDate", "telecom", "address")


def _scrub_phi(value):
    """Recursively redact PHI fields of any Patient resource in a payload."""
    if isinstance(value, dict):
        scrubbed = {key: _scrub_phi(item) for key, item in value.items()}
        if scrubbed.get("resourceType") == "Patient":
            for key in _PHI_PATIENT_KEYS:
                if key in scrubbed:
                    scrubbed[key] = "[REDACTED]"
        return scrubbed
    if isinstance(value, list):
        return [_scrub_phi(item) for item in value]
    return value


class CMSApiRequest(models.Model):
    class ApiCategory(models.TextChoices):
        ELIGIBILITY = "eligibility", _("Eligibility")
        ALIGNMENT = "alignment", _("Alignment")
        UNALIGNMENT = "unalignment", _("Unalignment")
        DATA_REPORTING = "data_reporting", _("Data Reporting")

    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    api_category = models.TextField(choices=ApiCategory.choices)
    endpoint = models.TextField()
    method = models.TextField()
    request_payload = models.JSONField()
    request_headers = models.JSONField()
    status_code = models.IntegerField(null=True, blank=True)
    beneficiary = models.ForeignKey(
        "identity.Beneficiary",
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="cms_requests",
    )
    requested_at = models.DateTimeField(auto_now_add=True)

    def save(self, *args, **kwargs):
        if not settings.ALLOW_SYNTHETIC_MBI:
            self.request_payload = _scrub_phi(self.request_payload)
        super().save(*args, **kwargs)

    def __str__(self):
        return f"{self.api_category}: {self.endpoint} ({self.status_code})"

    class Meta:
        app_label = "cms_integration"


class CMSApiResponse(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    request = models.ForeignKey(
        CMSApiRequest, on_delete=models.CASCADE, related_name="responses"
    )
    response_payload = models.JSONField()
    response_headers = models.JSONField()
    status_code = models.IntegerField()
    received_at = models.DateTimeField(auto_now_add=True)

    def save(self, *args, **kwargs):
        if not settings.ALLOW_SYNTHETIC_MBI:
            self.response_payload = _scrub_phi(self.response_payload)
        super().save(*args, **kwargs)

    def __str__(self):
        return f"Response: {self.request} ({self.status_code})"

    class Meta:
        app_label = "cms_integration"


class CMSApiSubmissionStatus(models.Model):
    """Durable tracking of a submitted CMS ACCESS operation.

    Created when an operation POST returns 202 + submission ID (per the CMS
    Operations Manual v0.9.12, clients must store submission IDs and request
    context so polling can resume after interruption/timeout). Each poll
    attempt is logged as its own CMSApiRequest/CMSApiResponse pair; this row
    records where to look next (next_poll_at) and which business record the
    final outcome applies to (target_table/target_record_id).
    """

    class Status(models.TextChoices):
        PENDING = "pending", _("Pending")
        IN_PROGRESS = "in_progress", _("In Progress")
        ERROR = "error", _("Error")
        COMPLETE = "complete", _("Complete")

    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    api_category = models.TextField(choices=CMSApiRequest.ApiCategory.choices)
    source_endpoint = models.TextField(
        default="",
        help_text="Operation that produced this submission (e.g. $check-eligibility)",
    )
    status = models.TextField(choices=Status.choices, default=Status.PENDING)
    submission_id = models.TextField(null=True, blank=True, unique=True)
    requested_at = models.DateTimeField(auto_now_add=True)
    next_poll_at = models.DateTimeField(null=True, blank=True)
    poll_attempts = models.PositiveIntegerField(default=0)
    target_table = models.TextField(
        null=True, blank=True, help_text="Model name the final outcome applies to"
    )
    target_record_id = models.UUIDField(null=True, blank=True)

    def __str__(self):
        return f"{self.api_category} {self.submission_id}: {self.status}"

    class Meta:
        app_label = "cms_integration"


class CMSClaimsFile(models.Model):
    class FileType(models.TextChoices):
        CLAIM = "claim", _("Claim")
        PAYMENT = "payment", _("Payment")
        RECOUPMENT = "recoupment", _("Recoupment")

    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    beneficiary = models.ForeignKey(
        "identity.Beneficiary",
        on_delete=models.PROTECT,
        related_name="cms_claims_files",
    )
    file_name = models.TextField()
    file_reference = models.TextField(null=True, blank=True)
    file_type = models.TextField(choices=FileType.choices)
    received_at = models.DateField()
    processed_at = models.DateTimeField(null=True, blank=True)
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"CMS file: {self.file_name} ({self.file_type})"

    class Meta:
        app_label = "cms_integration"


class CMSPaymentFile(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    beneficiary = models.ForeignKey(
        "identity.Beneficiary",
        on_delete=models.PROTECT,
        related_name="cms_payment_files",
    )
    care_period = models.ForeignKey(
        "monitoring.CarePeriod", on_delete=models.SET_NULL, null=True, blank=True
    )
    file_name = models.TextField()
    file_reference = models.TextField(null=True, blank=True)
    oap_amount = models.FloatField()
    payment_date = models.DateField()
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"Payment: {self.beneficiary} - ${self.oap_amount}"

    class Meta:
        app_label = "cms_integration"


class RecoupmentEvent(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    beneficiary = models.ForeignKey(
        "identity.Beneficiary",
        on_delete=models.PROTECT,
        related_name="recoupment_events",
    )
    care_period = models.ForeignKey("monitoring.CarePeriod", on_delete=models.PROTECT)
    amount = models.FloatField()
    reason = models.TextField(null=True, blank=True)
    event_date = models.DateField()
    status = models.TextField(default="notified")
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"Recoupment: {self.beneficiary} - ${self.amount} ({self.reason})"

    class Meta:
        app_label = "cms_integration"