"""Phase 11: Knowledge Management models — Playbooks + Lessons Learned."""

import uuid
from datetime import datetime

from sqlalchemy import (
    Boolean, Column, DateTime, ForeignKey,
    Index, Integer, String, Text, UniqueConstraint,
)
from sqlalchemy.dialects.postgresql import UUID, JSONB
from sqlalchemy.orm import relationship

from app.database import Base


# ── Playbooks ──────────────────────────────────────────────────────────────────

class Playbook(Base):
    """
    Structured runbook for a specific technique and playbook type.

    playbook_type: attack | detect | investigate | respond | hunt
    One playbook per (technique, type).  Edits increment ``version``
    and save a snapshot to ``PlaybookVersion``.
    """
    __tablename__ = "playbooks"

    id             = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    technique_id   = Column(
        UUID(as_uuid=True), ForeignKey("techniques.id", ondelete="CASCADE"), nullable=False
    )
    playbook_type  = Column(String(32), nullable=False)   # attack/detect/investigate/respond/hunt
    title          = Column(String(255), nullable=False)
    content        = Column(Text, nullable=False, default="")
    version        = Column(Integer, default=1, nullable=False)
    tools          = Column(JSONB, default=list)          # list of tool name strings
    prerequisites  = Column(JSONB, default=list)          # list of prerequisite strings
    created_by     = Column(
        UUID(as_uuid=True), ForeignKey("users.id", ondelete="SET NULL"), nullable=True
    )
    updated_by     = Column(
        UUID(as_uuid=True), ForeignKey("users.id", ondelete="SET NULL"), nullable=True
    )
    created_at     = Column(DateTime, default=datetime.utcnow)
    updated_at     = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
    is_active      = Column(Boolean, default=True)

    # Relationships
    technique  = relationship("Technique", foreign_keys=[technique_id])
    creator    = relationship("User", foreign_keys=[created_by])
    updater    = relationship("User", foreign_keys=[updated_by])
    versions   = relationship(
        "PlaybookVersion", back_populates="playbook",
        cascade="all, delete-orphan",
        order_by="PlaybookVersion.version.desc()",
    )

    __table_args__ = (
        UniqueConstraint("technique_id", "playbook_type", name="uq_playbook_technique_type"),
        Index("ix_playbooks_technique_id", "technique_id"),
        Index("ix_playbooks_type", "playbook_type"),
    )


class PlaybookVersion(Base):
    """Immutable snapshot of a playbook at a given version number."""

    __tablename__ = "playbook_versions"

    id           = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    playbook_id  = Column(
        UUID(as_uuid=True), ForeignKey("playbooks.id", ondelete="CASCADE"), nullable=False
    )
    version      = Column(Integer, nullable=False)
    title        = Column(String(255), nullable=False)
    content      = Column(Text, nullable=False, default="")
    tools        = Column(JSONB, default=list)
    prerequisites = Column(JSONB, default=list)
    changed_by   = Column(
        UUID(as_uuid=True), ForeignKey("users.id", ondelete="SET NULL"), nullable=True
    )
    change_note  = Column(String(500), nullable=True)
    created_at   = Column(DateTime, default=datetime.utcnow)

    playbook  = relationship("Playbook", back_populates="versions")
    changer   = relationship("User", foreign_keys=[changed_by])

    __table_args__ = (
        Index("ix_pb_versions_playbook_id", "playbook_id"),
        Index("ix_pb_versions_version",     "playbook_id", "version"),
    )


# ── Lessons Learned ────────────────────────────────────────────────────────────

class LessonLearned(Base):
    """
    Immutable post-mortem record linked to a test, campaign, attack-path or
    created manually.

    severity:    critical | high | medium | low | info
    entity_type: test | campaign | attack_path | manual
    """
    __tablename__ = "lessons_learned"

    id            = Column(UUID(as_uuid=True), primary_key=True, default=uuid.uuid4)
    title         = Column(String(255), nullable=False)
    what_happened = Column(Text, nullable=False, default="")
    root_cause    = Column(Text, nullable=False, default="")
    fix_applied   = Column(Text, nullable=True)
    severity      = Column(String(16), nullable=False, default="medium")
    entity_type   = Column(String(32), nullable=False, default="manual")
    entity_id     = Column(UUID(as_uuid=True), nullable=True)
    technique_ids = Column(JSONB, default=list)  # list of UUID strings
    tags          = Column(JSONB, default=list)
    created_by    = Column(
        UUID(as_uuid=True), ForeignKey("users.id", ondelete="SET NULL"), nullable=True
    )
    created_at    = Column(DateTime, default=datetime.utcnow)
    updated_at    = Column(DateTime, default=datetime.utcnow, onupdate=datetime.utcnow)
    is_active     = Column(Boolean, default=True)   # soft-delete (admin only)

    creator = relationship("User", foreign_keys=[created_by])

    __table_args__ = (
        Index("ix_ll_entity", "entity_type", "entity_id"),
        Index("ix_ll_severity", "severity"),
        Index("ix_ll_created_by", "created_by"),
    )