"""Detached transition values crossing the messaging tree ownership boundary."""
from __future__ import annotations


from dataclasses import dataclass
from enum import Enum

from ..models import MessageScope
from .identity import TreeIdentity
from .node import MessageReferenceKind, MessageState
from .snapshot import TreeSnapshot


class CancellationUiOwner(Enum):
    """Component responsible for the final user-visible cancellation edit."""


    RUNNER = "runner"
    WORKFLOW = "workflow"


class CancellationReason(Enum):
    """Customer operation that cancelled a running messaging claim."""

    STOP = "stop"
    CLEAR = "clear"


class AdmissionRejection(Enum):
    """Why a turn was not admitted to an execution tree."""

    DUPLICATE = "duplicate"
    PARENT_REMOVED = "parent_removed"


@dataclass(frozen=True, slots=True)
class NodeUiTarget:
    """Copied node coordinates needed for an external UI effect."""

    scope: MessageScope
    node_id: str
    status_message_id: str


@dataclass(frozen=True, slots=True)
class NodeClaim:
    """Exclusive permission to execute one node in a conversation tree."""

    identity: TreeIdentity
    claim_id: str
    node: NodeUiTarget
    prompt: str
    parent_session_id: str | None


@dataclass(frozen=True, slots=True)
class QueueEntry:
    """One immutable queue-position update."""

    node: NodeUiTarget
    position: int


@dataclass(frozen=True, slots=True)
class QueueDecision:
    """Atomic result of admitting a node to a tree."""

    claim: NodeClaim | None
    position: int | None
    snapshot: TreeSnapshot | None
    rejection: AdmissionRejection | None = None

    @property
    def accepted(self) -> bool:
        return self.snapshot is not None


@dataclass(frozen=True, slots=True)
class CompletionResult:
    """Atomic result of releasing a claim and selecting its successor."""

    next_claim: NodeClaim | None
    queue: tuple[QueueEntry, ...]


@dataclass(frozen=True, slots=True)
class CancellationEffect:
    """Copied cancellation fact for the UI layer."""

    node: NodeUiTarget
    ui_owner: CancellationUiOwner


@dataclass(frozen=True, slots=True)
class TreeCancellation:
    """Single-tree cancellation transition consumed by the manager."""

    nodes: tuple[NodeUiTarget, ...]
    active_claim: NodeClaim | None
    queue_update: tuple[QueueEntry, ...] | None


@dataclass(frozen=True, slots=True)
class CancellationResult:
    """External effects and persistence snapshots from a cancellation request."""

    effects: tuple[CancellationEffect, ...] = ()
    snapshots: tuple[TreeSnapshot, ...] = ()


@dataclass(frozen=True, slots=True)
class MessageSubtreeRemoval:
    """Single-tree atomic cancellation and reference-subtree removal."""

    cancellation: TreeCancellation
    removed_message_ids: frozenset[str]
    removed_entire_tree: bool


@dataclass(frozen=True, slots=True)
class MessageSubtreeRemovalResult:
    """Manager result for a literal message-subtree clear."""

    cancellation: CancellationResult
    removed_tree_identity: TreeIdentity | None
    delete_message_ids: frozenset[str]
    tree_matched: bool


@dataclass(frozen=True, slots=True)
class ReplyTarget:
    """Resolved reply destination and advisory position before admission."""

    node_id: str
    reference_id: str
    reference_kind: MessageReferenceKind
    queue_position: int | None


@dataclass(frozen=True, slots=True)
class NodeView:
    """Immutable read model for diagnostics, tests, and smoke assertions."""

    identity: TreeIdentity
    node_id: str
    state: MessageState
    parent_id: str | None
    session_id: str | None


@dataclass(frozen=True, slots=True)
class FailureResult:
    """Atomic node failure plus copied child UI effects."""

    affected: tuple[NodeUiTarget, ...]
    queue_update: tuple[QueueEntry, ...] | None
    snapshot: TreeSnapshot | None


__all__ = [
    "AdmissionRejection",
    "CancellationEffect",
    "CancellationReason",
    "CancellationResult",
    "CancellationUiOwner",
    "CompletionResult",
    "FailureResult",
    "MessageSubtreeRemoval",
    "MessageSubtreeRemovalResult",
    "NodeClaim",
    "NodeUiTarget",
    "NodeView",
    "QueueDecision",
    "QueueEntry",
    "ReplyTarget",
    "TreeCancellation",
]