"""Test workflow service — state-machine transitions for the Red/Blue validation flow.

Controls which state transitions are valid and exposes high-level helpers
for each step in the test lifecycle:

    draft → red_executing → blue_evaluating → in_review → validated / rejected
                                                                  ↓
                                                           rejected → draft

Every public function validates the transition, mutates the test, and writes
an audit-log entry.  The caller (router) is responsible for committing the
session via the Unit of Work pattern.
"""

import logging
from datetime import datetime

from sqlalchemy.orm import Session

from app.config import settings
from app.domain.exceptions import InvalidOperationError, InvalidTransitionError
from app.domain.test_entity import TestEntity
from app.models.enums import TestState, TeamSide
from app.models.evidence import Evidence
from app.models.test import Test
from app.models.user import User
from app.services.audit_service import log_action
from app.services.notification_service import notify_test_state_change, create_notification

logger = logging.getLogger(__name__)

# ---------------------------------------------------------------------------
# Valid transition map
# ---------------------------------------------------------------------------

VALID_TRANSITIONS: dict[TestState, list[TestState]] = {
    TestState.draft:           [TestState.red_executing],
    TestState.red_executing:   [TestState.blue_evaluating],
    TestState.blue_evaluating: [TestState.in_review],
    TestState.in_review:       [TestState.validated, TestState.rejected],
    TestState.rejected:        [TestState.draft],
    TestState.validated:       [],  # terminal state
}


# ---------------------------------------------------------------------------
# Core helpers
# ---------------------------------------------------------------------------


def can_transition(test: Test, target_state: TestState) -> bool:
    """Return *True* if moving *test* to *target_state* is allowed."""
    current = test.state if isinstance(test.state, TestState) else TestState(test.state)
    return target_state in VALID_TRANSITIONS.get(current, [])


def transition_state(
    db: Session,
    test: Test,
    target_state: TestState,
    user: User,
    *,
    action_name: str = "transition_state",
    extra_details: dict | None = None,
) -> Test:
    """Validate and perform a state transition, log it, and flush.

    Delegates validation to :class:`TestEntity` which raises
    :class:`InvalidStateTransition` (aliased as ``InvalidTransitionError``)
    when the transition is illegal.  The entity is authoritative for which
    transitions are valid; the module-level ``VALID_TRANSITIONS`` dict is
    kept temporarily for backward compatibility of ``can_transition()``.
    """
    entity = TestEntity.from_orm(test)
    previous_state = entity.transition_to(target_state)

    test.state = entity.state
    db.flush()

    details: dict = {
        "previous_state": previous_state,
        "new_state": target_state.value,
        "test_name": test.name,
        "technique_id": str(test.technique_id),
    }
    if extra_details:
        details.update(extra_details)

    log_action(
        db,
        user_id=user.id,
        action=action_name,
        entity_type="test",
        entity_id=test.id,
        details=details,
    )

    try:
        notify_test_state_change(db, test, target_state.value)
    except Exception as e:
        logger.warning("Notification failed for test %s: %s", test.id, e, exc_info=True)

    return test


# ---------------------------------------------------------------------------
# Lifecycle convenience functions
# ---------------------------------------------------------------------------


def start_execution(db: Session, test: Test, user: User) -> Test:
    """Move from ``draft`` → ``red_executing``."""
    entity = TestEntity.from_orm(test)
    entity.start_execution()
    entity.apply_to(test)
    db.flush()

    log_action(
        db,
        user_id=user.id,
        action="start_execution",
        entity_type="test",
        entity_id=test.id,
        details={
            "previous_state": "draft",
            "new_state": test.state.value,
            "test_name": test.name,
            "technique_id": str(test.technique_id),
        },
    )

    try:
        notify_test_state_change(db, test, test.state.value)
    except Exception as e:
        logger.warning("Notification failed for test %s: %s", test.id, e, exc_info=True)

    try:
        from app.services.jira_service import push_test_event
        push_test_event(db, test, user, "red_executing")
    except Exception as e:
        logger.warning("Jira push failed for test %s: %s", test.id, e, exc_info=True)

    return test


def submit_red_evidence(db: Session, test: Test, user: User) -> Test:
    """Move from ``red_executing`` → ``blue_evaluating``.

    Called by **red_tech** once they have finished documenting the attack.
    Requires at least one Red Team evidence file to be uploaded.
    Stops the Red Team timer and creates an automatic worklog.
    Starts the Blue Team timer by recording ``blue_started_at``.
    """
    # Evidence is mandatory before submitting
    red_evidence_count = (
        db.query(Evidence)
        .filter(Evidence.test_id == test.id, Evidence.team == TeamSide.red)
        .count()
    )
    if red_evidence_count == 0:
        raise InvalidOperationError(
            "Cannot submit to Blue Team: at least one Red Team evidence file must be uploaded first."
        )

    now = datetime.utcnow()

    # Auto-resume if paused
    paused_extra = 0
    if test.paused_at is not None:
        paused_extra = max(int((now - test.paused_at).total_seconds()), 0)
        test.paused_at = None

    test = transition_state(
        db, test, TestState.blue_evaluating, user,
        action_name="submit_red_evidence",
    )

    # Create automatic worklog for Red Team phase (subtract paused time)
    _create_phase_worklog(
        db,
        test=test,
        user=user,
        phase_started_at=test.red_started_at,
        phase_ended_at=now,
        paused_seconds=(test.red_paused_seconds or 0) + paused_extra,
        activity_type="red_team_execution",
        description=f"Red Team execution: {test.name}",
    )

    # Start Blue Team timer
    test.blue_started_at = now
    test.blue_paused_seconds = 0

    try:
        from app.services.jira_service import push_test_event
        push_test_event(db, test, user, "blue_evaluating")
    except Exception as e:
        logger.warning("Jira push failed for test %s: %s", test.id, e, exc_info=True)

    return test


def start_blue_work(db: Session, test: Test, user: User) -> Test:
    """Mark that a blue tech has picked up this test to start evaluating.

    Sets blue_work_started_at. Only valid in blue_evaluating state and
    only if blue_work_started_at is not already set.
    """
    if test.state != TestState.blue_evaluating:
        raise InvalidOperationError(
            f"Cannot start blue work in '{test.state.value}' state"
        )
    if test.blue_work_started_at is not None:
        raise InvalidOperationError("Blue work already started")

    test.blue_work_started_at = datetime.utcnow()
    db.flush()

    log_action(
        db,
        user_id=user.id,
        action="start_blue_work",
        entity_type="test",
        entity_id=test.id,
        details={"test_name": test.name},
    )

    try:
        notify_test_state_change(db, test, "blue_work_started")
    except Exception as e:
        logger.warning("Notification failed for test %s: %s", test.id, e, exc_info=True)

    return test


def submit_blue_evidence(db: Session, test: Test, user: User) -> Test:
    """Move from ``blue_evaluating`` → ``in_review``.

    Called by **blue_tech** once they have finished documenting detection.
    Requires at least one Blue Team evidence file to be uploaded.
    Stops the Blue Team timer and creates an automatic worklog.
    Uses blue_work_started_at as the phase start for Tempo if available,
    otherwise falls back to blue_started_at (queue-entry timestamp).
    """
    # Evidence is mandatory before submitting
    blue_evidence_count = (
        db.query(Evidence)
        .filter(Evidence.test_id == test.id, Evidence.team == TeamSide.blue)
        .count()
    )
    if blue_evidence_count == 0:
        raise InvalidOperationError(
            "Cannot submit for review: at least one Blue Team evidence file must be uploaded first."
        )

    now = datetime.utcnow()

    # Auto-resume if paused
    paused_extra = 0
    if test.paused_at is not None:
        paused_extra = max(int((now - test.paused_at).total_seconds()), 0)
        test.paused_at = None

    test = transition_state(
        db, test, TestState.in_review, user,
        action_name="submit_blue_evidence",
    )

    # Create automatic worklog for Blue Team phase (subtract paused time).
    # Use blue_work_started_at (actual pick-up time) when available so the
    # Tempo worklog reflects real working time, not just queue time.
    _create_phase_worklog(
        db,
        test=test,
        user=user,
        phase_started_at=test.blue_work_started_at or test.blue_started_at,
        phase_ended_at=now,
        paused_seconds=(test.blue_paused_seconds or 0) + paused_extra,
        activity_type="blue_team_evaluation",
        description=f"Blue Team evaluation: {test.name}",
    )

    try:
        from app.services.jira_service import push_test_event
        push_test_event(db, test, user, "in_review")
    except Exception as e:
        logger.warning("Jira push failed for test %s: %s", test.id, e, exc_info=True)

    return test


def pause_timer(db: Session, test: Test, user: User) -> Test:
    """Pause the active phase timer.

    Can only be called when the test is in ``red_executing`` or
    ``blue_evaluating`` and is not already paused.
    """
    if test.state not in (TestState.red_executing, TestState.blue_evaluating):
        raise InvalidOperationError(
            f"Cannot pause timer in '{test.state.value}' state"
        )
    if test.paused_at is not None:
        raise InvalidOperationError("Timer is already paused")

    test.paused_at = datetime.utcnow()
    log_action(
        db,
        user_id=user.id,
        action="pause_timer",
        entity_type="test",
        entity_id=test.id,
        details={"state": test.state.value},
    )
    return test


def resume_timer(db: Session, test: Test, user: User) -> Test:
    """Resume a paused phase timer.

    Accumulates the paused duration into the appropriate counter so
    it is subtracted from the final worklog.
    """
    if test.paused_at is None:
        raise InvalidOperationError("Timer is not paused")

    now = datetime.utcnow()
    paused_seconds = max(int((now - test.paused_at).total_seconds()), 0)

    if test.state == TestState.red_executing:
        test.red_paused_seconds = (test.red_paused_seconds or 0) + paused_seconds
    elif test.state == TestState.blue_evaluating:
        test.blue_paused_seconds = (test.blue_paused_seconds or 0) + paused_seconds

    test.paused_at = None
    log_action(
        db,
        user_id=user.id,
        action="resume_timer",
        entity_type="test",
        entity_id=test.id,
        details={"paused_seconds": paused_seconds, "state": test.state.value},
    )
    return test


def _create_phase_worklog(
    db: Session,
    *,
    test: Test,
    user: User,
    phase_started_at: datetime | None,
    phase_ended_at: datetime,
    paused_seconds: int = 0,
    activity_type: str,
    description: str,
) -> None:
    """Create an automatic, integrity-hashed worklog for a completed phase.

    Subtracts accumulated *paused_seconds* from the gross elapsed time
    so the worklog reflects only active working time.
    Also triggers Tempo sync if the test has a Jira link.
    """
    if not phase_started_at:
        logger.warning(
            "No phase start timestamp for test %s (%s), skipping worklog",
            test.id, activity_type,
        )
        return

    gross_seconds = int((phase_ended_at - phase_started_at).total_seconds())
    duration_seconds = max(gross_seconds - paused_seconds, 1)

    try:
        from app.services.worklog_service import create_worklog

        wl = create_worklog(
            db,
            entity_type="test",
            entity_id=test.id,
            user_id=user.id,
            activity_type=activity_type,
            started_at=phase_started_at,
            ended_at=phase_ended_at,
            duration_seconds=duration_seconds,
            description=description,
        )
        logger.info(
            "Auto-worklog created for test %s: %s, %ds (worklog %s)",
            test.id, activity_type, duration_seconds, wl.id,
        )

        # Sync to Tempo: only red_team_execution, using the already-computed
        # duration so the Tempo entry is identical to the Aegis worklog.
        try:
            from app.services.tempo_service import auto_log_test_worklog
            tempo_result = auto_log_test_worklog(db, test, user, activity_type, duration_seconds)
            if tempo_result and isinstance(tempo_result, dict):
                wl.tempo_synced = datetime.utcnow()
                wl.tempo_worklog_id = str(tempo_result.get("tempoWorklogId", ""))
                db.flush()
        except Exception as e:
            logger.warning("Tempo sync failed for worklog: %s", e, exc_info=True)

    except Exception as e:
        logger.error("Failed to create auto-worklog for test %s: %s", test.id, e, exc_info=True)


def validate_as_red_lead(
    db: Session,
    test: Test,
    user: User,
    validation_status: str,
    notes: str | None = None,
) -> Test:
    """Record Red Lead's validation decision.

    Delegates validation rules and state mutation entirely to
    :meth:`TestEntity.validate_red`.  If both leads have voted the
    entity will also advance the test to ``validated`` or ``rejected``.
    """
    entity = TestEntity.from_orm(test)
    entity.validate_red(validation_status, by=user.id, notes=notes)
    entity.apply_to(test)
    db.flush()

    log_action(
        db,
        user_id=user.id,
        action="validate_as_red_lead",
        entity_type="test",
        entity_id=test.id,
        details={
            "validation_status": validation_status,
            "notes": notes,
            "technique_id": str(test.technique_id),
        },
    )

    _dispatch_dual_validation_effects(db, test, entity, actor=user)
    return test


def validate_as_blue_lead(
    db: Session,
    test: Test,
    user: User,
    validation_status: str,
    notes: str | None = None,
) -> Test:
    """Record Blue Lead's validation decision.

    Delegates validation rules and state mutation entirely to
    :meth:`TestEntity.validate_blue`.  If both leads have voted the
    entity will also advance the test to ``validated`` or ``rejected``.
    """
    entity = TestEntity.from_orm(test)
    entity.validate_blue(validation_status, by=user.id, notes=notes)
    entity.apply_to(test)
    db.flush()

    log_action(
        db,
        user_id=user.id,
        action="validate_as_blue_lead",
        entity_type="test",
        entity_id=test.id,
        details={
            "validation_status": validation_status,
            "notes": notes,
            "technique_id": str(test.technique_id),
        },
    )

    _dispatch_dual_validation_effects(db, test, entity, actor=user)
    return test


def check_dual_validation(db: Session, test: Test) -> Test:
    """Evaluate both leads' decisions and advance the test if both have voted.

    All state mutation is delegated to :meth:`TestEntity.check_dual_validation`.
    This function never assigns ``test.state`` directly.
    """
    entity = TestEntity.from_orm(test)
    entity.check_dual_validation()
    entity.apply_to(test)

    _dispatch_dual_validation_effects(db, test, entity)
    return test


def _dispatch_dual_validation_effects(
    db: Session, test: Test, entity: TestEntity, actor: User | None = None
) -> None:
    """Dispatch side effects (notifications, cache, Jira) based on domain events."""
    for event in entity.events:
        if event.name == "dual_validation_approved":
            try:
                from app.services.score_cache import invalidate
                invalidate()
            except Exception as e:
                logger.warning("Score cache invalidation failed: %s", e, exc_info=True)
            try:
                notify_test_state_change(db, test, "validated")
            except Exception as e:
                logger.warning(
                    "Notification failed for test %s (validated): %s",
                    test.id, e, exc_info=True,
                )
            if actor:
                try:
                    from app.services.jira_service import push_test_event
                    push_test_event(db, test, actor, "validated")
                except Exception as e:
                    logger.warning("Jira push failed for test %s: %s", test.id, e, exc_info=True)

        elif event.name == "dual_validation_rejected":
            try:
                notify_test_state_change(db, test, "rejected")
            except Exception as e:
                logger.warning(
                    "Notification failed for test %s (rejected): %s",
                    test.id, e, exc_info=True,
                )
            if actor:
                try:
                    from app.services.jira_service import push_test_event
                    push_test_event(db, test, actor, "rejected")
                except Exception as e:
                    logger.warning("Jira push failed for test %s: %s", test.id, e, exc_info=True)


def handle_remediation_completed(db: Session, test: Test, user: User) -> Test | None:
    """Create a re-test when remediation is completed.

    When a test's remediation_status changes to 'completed', this function
    creates a new test (retest) with the same base data to verify that the
    fix was effective.

    Prevents infinite loops by enforcing ``MAX_RETEST_COUNT``.

    Returns the new retest or *None* if the limit was reached.
    """
    # Always reference the original test, not an intermediate retest
    original_test_id = test.retest_of or test.id

    if test.retest_count >= settings.MAX_RETEST_COUNT:
        # Max retests reached — notify and bail out
        if test.created_by:
            create_notification(
                db,
                user_id=test.created_by,
                type="max_retests_reached",
                title="Maximum retests reached",
                message=(
                    f'Test "{test.name}" has reached the maximum of '
                    f'{settings.MAX_RETEST_COUNT} retests. Manual review required.'
                ),
                entity_type="test",
                entity_id=test.id,
            )

        log_action(
            db,
            user_id=user.id,
            action="max_retests_reached",
            entity_type="test",
            entity_id=test.id,
            details={
                "retest_count": test.retest_count,
                "max_allowed": settings.MAX_RETEST_COUNT,
                "original_test_id": str(original_test_id),
            },
        )
        return None

    retest = Test(
        technique_id=test.technique_id,
        name=f"[Retest #{test.retest_count + 1}] {test.name.replace(f'[Retest #{test.retest_count}] ', '')}",
        description=test.description,
        platform=test.platform,
        procedure_text=test.procedure_text,
        tool_used=test.tool_used,
        state=TestState.draft,
        created_by=test.created_by,
        retest_of=original_test_id,
        retest_count=test.retest_count + 1,
    )
    db.add(retest)
    db.flush()

    log_action(
        db,
        user_id=user.id,
        action="create_retest",
        entity_type="test",
        entity_id=retest.id,
        details={
            "original_test_id": str(original_test_id),
            "retest_number": retest.retest_count,
            "source_test_id": str(test.id),
        },
    )

    # Notify the test creator and any red_tech users
    if test.created_by:
        create_notification(
            db,
            user_id=test.created_by,
            type="retest_created",
            title="Re-test created",
            message=(
                f'A re-test has been automatically created for "{test.name}" '
                f'after remediation was completed.'
            ),
            entity_type="test",
            entity_id=retest.id,
        )

    db.flush()
    return retest


def get_retest_chain(db: Session, test_id) -> list[Test]:
    """Return the full chain of retests for a given test.

    Includes the original test and all subsequent retests, ordered
    by retest_count.
    """
    import uuid as _uuid

    tid = _uuid.UUID(str(test_id)) if not isinstance(test_id, _uuid.UUID) else test_id

    # Find the original test first
    test = db.query(Test).filter(Test.id == tid).first()
    if not test:
        return []

    original_id = test.retest_of or test.id

    # Get original
    original = db.query(Test).filter(Test.id == original_id).first()
    if not original:
        return [test]

    # Get all retests of the original
    retests = (
        db.query(Test)
        .filter(Test.retest_of == original_id)
        .order_by(Test.retest_count)
        .all()
    )

    return [original] + retests


def reopen_test(db: Session, test: Test, user: User) -> Test:
    """Move a ``rejected`` test back to ``draft``, clearing validation fields.

    This allows the teams to redo the test cycle.
    """
    test = transition_state(
        db, test, TestState.draft, user,
        action_name="reopen_test",
    )

    # Clear dual-validation fields
    test.red_validation_status = None
    test.red_validated_by = None
    test.red_validated_at = None
    test.red_validation_notes = None

    test.blue_validation_status = None
    test.blue_validated_by = None
    test.blue_validated_at = None
    test.blue_validation_notes = None

    # Clear phase timing fields
    test.red_started_at = None
    test.blue_started_at = None
    test.blue_work_started_at = None
    test.paused_at = None
    test.red_paused_seconds = 0
    test.blue_paused_seconds = 0

    try:
        from app.services.jira_service import push_test_event
        push_test_event(db, test, user, "draft")
    except Exception as e:
        logger.warning("Jira push failed for test %s: %s", test.id, e, exc_info=True)

    return test