"""
Governance & Audit — Reviews, safety signals, audit events, offshore pseudonymous review.
"""

import uuid

from django.db import models


class PhysicianReview(models.Model):
    REVIEW_TYPE_CHOICES = [
        ("intake_approval", "Intake Approval"),
        ("eligibility_decision", "Eligibility Decision"),
        ("enrollment_decision", "Enrollment Decision"),
        ("observation_approval", "Observation Approval"),
        ("pause_escalation", "Pause Escalation"),
        ("monthly_summary", "Monthly Summary"),
        ("other", "Other"),
    ]
    DECISION_CHOICES = [
        ("approved", "Approved"),
        ("rejected", "Rejected"),
        ("deferred", "Deferred"),
        ("needs_more_info", "Needs More Info"),
        ("pause", "Pause"),
        ("escalate", "Escalate"),
    ]
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    intake_record = models.ForeignKey(
        "intake.IntakeRecord",
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="physician_reviews",
    )
    beneficiary = models.ForeignKey(
        "identity.Beneficiary",
        on_delete=models.SET_NULL,
        null=True,
        blank=True,
        related_name="physician_reviews",
    )
    care_period = models.ForeignKey(
        "monitoring.CarePeriod", on_delete=models.SET_NULL, null=True, blank=True
    )
    review_type = models.TextField(choices=REVIEW_TYPE_CHOICES)
    review_subject_id = models.UUIDField(null=True, blank=True)
    review_subject_type = models.TextField()
    decision = models.TextField(choices=DECISION_CHOICES)
    notes = models.TextField(null=True, blank=True)
    reviewed_by = models.ForeignKey("identity.User", on_delete=models.PROTECT)
    reviewed_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"Review: {self.review_type} -> {self.decision}"

    class Meta:
        app_label = "governance"


class ClinicalReviewTask(models.Model):
    TASK_TYPE_CHOICES = [
        ("observation_review", "Observation Review"),
        ("safety_signal_review", "Safety Signal Review"),
        ("monthly_summary_review", "Monthly Summary Review"),
        ("adverse_event_review", "Adverse Event Review"),
    ]
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    beneficiary = models.ForeignKey(
        "identity.Beneficiary", on_delete=models.SET_NULL, null=True, blank=True
    )
    care_period = models.ForeignKey(
        "monitoring.CarePeriod", on_delete=models.SET_NULL, null=True, blank=True
    )
    assigned_to = models.ForeignKey("identity.User", on_delete=models.PROTECT)
    task_type = models.TextField(choices=TASK_TYPE_CHOICES)
    status = models.TextField(default="pending")
    assigned_at = models.DateTimeField(auto_now_add=True)
    completed_at = models.DateTimeField(null=True, blank=True)
    notes = models.TextField(null=True, blank=True)

    def __str__(self):
        return f"Task: {self.task_type} -> {self.assigned_to} ({self.status})"

    class Meta:
        app_label = "governance"


class SafetySignalEvent(models.Model):
    SEVERITY_CHOICES = [
        ("red", "Red"),
        ("yellow", "Yellow"),
        ("green", "Green"),
    ]
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    beneficiary = models.ForeignKey(
        "identity.Beneficiary", on_delete=models.PROTECT, related_name="safety_signals"
    )
    care_period = models.ForeignKey("monitoring.CarePeriod", on_delete=models.PROTECT)
    signal_severity = models.TextField(choices=SEVERITY_CHOICES)
    signal_type = models.TextField()
    signal_details = models.JSONField()
    source_record_id = models.UUIDField(null=True, blank=True)
    auto_generated = models.BooleanField(default=False)
    review_status = models.TextField(default="pending")
    reviewed_by = models.ForeignKey(
        "identity.User", on_delete=models.SET_NULL, null=True, blank=True
    )
    reviewed_at = models.DateTimeField(null=True, blank=True)
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return (
            f"Signal: {self.beneficiary} - {self.signal_type} ({self.signal_severity})"
        )

    class Meta:
        app_label = "governance"


class ClinicalEventLog(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    beneficiary = models.ForeignKey(
        "identity.Beneficiary", on_delete=models.PROTECT, related_name="event_logs"
    )
    care_period = models.ForeignKey("monitoring.CarePeriod", on_delete=models.PROTECT)
    event_date = models.DateField()
    event_type = models.TextField()
    event_details = models.TextField()
    source_system = models.TextField()
    requires_review = models.BooleanField(default=False)
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"Event: {self.beneficiary} - {self.event_type} ({self.event_date})"

    class Meta:
        app_label = "governance"


class CareTeamReviewTask(models.Model):
    TRIGGER_CHOICES = [
        ("safety_signal", "Safety Signal"),
        ("missed_checkin", "Missed Checkin"),
        ("symptom_escalation", "Symptom Escalation"),
        ("monthly_summary", "Monthly Summary"),
        ("adverse_event", "Adverse Event"),
    ]
    PRIORITY_CHOICES = [
        ("low", "Low"),
        ("medium", "Medium"),
        ("high", "High"),
        ("urgent", "Urgent"),
    ]
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    beneficiary = models.ForeignKey(
        "identity.Beneficiary", on_delete=models.PROTECT, related_name="care_team_tasks"
    )
    care_period = models.ForeignKey("monitoring.CarePeriod", on_delete=models.PROTECT)
    assigned_to = models.ForeignKey(
        "identity.User", on_delete=models.SET_NULL, null=True, blank=True
    )
    trigger_type = models.TextField(choices=TRIGGER_CHOICES)
    trigger_record_id = models.UUIDField()
    priority = models.TextField(choices=PRIORITY_CHOICES)
    status = models.TextField(default="pending")
    notes = models.TextField(null=True, blank=True)
    assigned_at = models.DateTimeField(auto_now_add=True)
    completed_at = models.DateTimeField(null=True, blank=True)

    def __str__(self):
        return f"Task: {self.beneficiary} - {self.trigger_type} ({self.priority})"

    class Meta:
        app_label = "governance"


class AuditEvent(models.Model):
    ACTION_CHOICES = [
        ("view", "View"),
        ("create", "Create"),
        ("edit", "Edit"),
        ("approve", "Approve"),
        ("reject", "Reject"),
        ("export", "Export"),
        ("delete", "Delete"),
        ("lock", "Lock"),
        ("submit_to_cms", "Submit to CMS"),
    ]
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    # auth.User (Django's login user), not identity.User: audit rows record who
    # acted via request.user in the admin/API; system paths leave it null.
    user = models.ForeignKey(
        "auth.User", on_delete=models.SET_NULL, null=True, blank=True
    )
    action = models.TextField(choices=ACTION_CHOICES)
    target_table = models.TextField()
    target_record_id = models.UUIDField()
    changed_fields = models.JSONField(null=True, blank=True)
    old_value_hash = models.TextField(null=True, blank=True)
    new_value_hash = models.TextField(null=True, blank=True)
    ip_address = models.TextField(null=True, blank=True)
    user_agent = models.TextField(null=True, blank=True)
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"Audit: {self.user} {self.action} on {self.target_table}"

    class Meta:
        app_label = "governance"
        ordering = ["-created_at"]
        indexes = [
            models.Index(fields=["target_table", "target_record_id"]),
            models.Index(fields=["user", "created_at"]),
        ]


class PseudonymousCaseRecord(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    beneficiary = models.ForeignKey(
        "identity.Beneficiary",
        on_delete=models.PROTECT,
        related_name="pseudonymous_cases",
    )
    case_id = models.TextField(unique=True)
    age_band = models.TextField(null=True, blank=True)
    sex = models.TextField()
    clinical_track = models.TextField(null=True, blank=True)
    care_period = models.ForeignKey("monitoring.CarePeriod", on_delete=models.PROTECT)
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"Case: {self.case_id} (track={self.clinical_track}, sex={self.sex})"

    class Meta:
        app_label = "governance"


class PseudonymousClinicalPacket(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, editable=False)
    case_record = models.ForeignKey(
        PseudonymousCaseRecord, on_delete=models.CASCADE, related_name="packets"
    )
    packet_type = models.TextField()
    structured_data = models.JSONField()
    deidentified_at = models.DateTimeField(auto_now_add=True)
    deidentification_method = models.TextField(null=True, blank=True)
    review_status = models.TextField(default="pending")
    reviewed_by = models.ForeignKey(
        "identity.User", on_delete=models.SET_NULL, null=True, blank=True
    )
    reviewed_at = models.DateTimeField(null=True, blank=True)
    created_at = models.DateTimeField(auto_now_add=True)

    def __str__(self):
        return f"Packet: {self.case_record} ({self.packet_type})"

    class Meta:
        app_label = "governance"