"""Shared data models for the structural rewrite engine."""

from __future__ import annotations

from dataclasses import dataclass, field
from typing import Any


@dataclass
class DocumentBlock:
    """A contiguous document region with rewrite policy."""

    text: str
    kind: str = "paragraph"  # paragraph|heading|list|table|code|formula|bibliography|blank
    rewriteable: bool = True
    index: int = 0
    meta: dict[str, Any] = field(default_factory=dict)


@dataclass
class SentenceSlots:
    """Constituent spans extracted for template fill."""

    text: str
    subject: str = ""
    verb: str = ""
    verb_phrase: str = ""
    object: str = ""
    place: str = ""
    time: str = ""
    manner: str = ""
    negation: str = ""
    leftover: str = ""
    entities: list[str] = field(default_factory=list)
    auxiliaries: list[str] = field(default_factory=list)
    subject_is_proper: bool = False
    verb_starts_with_aux: bool = False
    confidence: float = 0.0
    sentence_type: str = "unsupported"
    reasons: list[str] = field(default_factory=list)


@dataclass
class TemplateCandidate:
    template_id: str
    confidence: float


@dataclass
class LexicalChange:
    """One context-validated vocabulary substitution."""

    original: str
    replacement: str
    token_index: int
    lemma: str = ""
    synset_id: str = ""
    confidence: float = 0.0


@dataclass
class RewritePlan:
    """Decision object before generation."""

    safe: bool
    slots: SentenceSlots | None = None
    template_id: str = ""
    candidates: list[TemplateCandidate] = field(default_factory=list)
    fixed_spans: list[str] = field(default_factory=list)
    movable: list[str] = field(default_factory=list)
    skip_reason: str = ""
    confidence: float = 0.0


@dataclass
class SentenceRecord:
    """Per-sentence rewrite report."""

    index: int
    original: str
    rewritten: str
    confidence: float
    status: str  # rewritten|skipped|reverted|passthrough
    template_id: str = ""
    sentence_type: str = ""
    reasons: list[str] = field(default_factory=list)
    block_index: int = 0
    lexical_changes: list[LexicalChange] = field(default_factory=list)


@dataclass
class EngineStats:
    batches: int = 0
    blocks: int = 0
    sentences: int = 0
    rewritten: int = 0
    skipped: int = 0
    reverted: int = 0
    passthrough: int = 0
    lexical_refined: int = 0
    forced_rewrites: int = 0
    paraphrased: int = 0
    seconds: float = 0.0
    reasons: dict[str, int] = field(default_factory=dict)

    def bump(self, reason: str) -> None:
        key = (reason or "other").split(":")[0]
        self.reasons[key] = self.reasons.get(key, 0) + 1


@dataclass
class EngineResult:
    text: str
    sentences: list[SentenceRecord] = field(default_factory=list)
    skipped: list[SentenceRecord] = field(default_factory=list)
    mapping: list[tuple[str, str]] = field(default_factory=list)
    stats: EngineStats = field(default_factory=EngineStats)
    notes: str = ""
    engine: str = "structural-reorder"
    input_words: int = 0
    output_words: int = 0
    changed: bool = False
    similarity: float = 1.0