"""Pydantic v2 schemas for all API request and response payloads."""

from datetime import UTC, datetime
from enum import Enum, StrEnum
from typing import Any

from pydantic import BaseModel, Field, field_validator, model_validator

# ── Generation mode ────────────────────────────────────────────────────────────

class GenerationMode(StrEnum):
    """The three AI operation modes exposed in the UI."""

    generate = "generate"
    """Personalised content generation: RAG retrieval + style adaptation."""

    proofread = "proofread"
    """Proofreading: grammar, clarity, and style-consistency review."""

    enhance = "enhance"
    """Technical enhancement: expand depth using uploaded + system documents."""


# ── Writing style ──────────────────────────────────────────────────────────────

class WritingStyleProfile(BaseModel):
    """Detected writing style extracted from the user's uploaded documents."""

    tone: str = Field(default="formal", description="Overall tone: formal | semi-formal | technical | casual")
    formality_level: str = Field(default="professional", description="Professional | academic | conversational")
    avg_sentence_complexity: str = Field(default="moderate", description="Simple | moderate | complex")
    vocabulary_level: str = Field(default="technical", description="Basic | intermediate | technical | specialist")
    common_phrases: list[str] = Field(default_factory=list, description="Frequently used phrases or openers")
    structural_patterns: list[str] = Field(default_factory=list, description="Observed sentence/paragraph patterns")
    writing_style_summary: str = Field(
        default="Professional RICS survey style with factual, measured language.",
        description="Short human-readable summary of the detected style",
    )
    example_paragraphs: list[str] = Field(
        default_factory=list,
        description="Representative paragraphs from this surveyor's reports used as few-shot style guides",
    )


# ── Upload ────────────────────────────────────────────────────────────────────

class UploadResponse(BaseModel):
    """Response returned after a successful file upload."""

    document_id: str
    tenant_id: str
    filename: str
    status: str
    message: str


class DocumentSurveyLevelUpdate(BaseModel):
    """Assign the RICS Home Survey **product** tier to an uploaded document (library filtering)."""

    survey_level: int = Field(
        ...,
        ge=1,
        le=3,
        description="1 = Condition Report, 2 = HomeBuyer / Level 2, 3 = Building Survey / Level 3",
    )


class DocumentSurveyLevelResponse(BaseModel):
    """Acknowledgement after updating ``survey_level`` on a document."""

    document_id: str
    survey_level: int
    detail: str = "survey_level saved; future RAG uses this tier for library filtering."


class SurveyLevelScoreCandidate(BaseModel):
    """One tier and its relative score from the classifier."""

    survey_level: int = Field(ge=0, le=3)
    score: float


class SurveyLevelClassificationItem(BaseModel):
    """Per-document tier suggestion with explicit rationale (no silent auto-apply).

    ``predicted_survey_level=0`` means the classifier could not determine the tier
    (file unreadable, too short, no corpus, no phrase signals). The UI should prompt
    the user to select the tier manually rather than auto-applying a guess.
    """

    document_id: str
    filename: str
    predicted_survey_level: int = Field(ge=0, le=3)
    confidence: float = Field(ge=0.0, le=1.0)
    candidates: list[SurveyLevelScoreCandidate]
    rationale: str


class SurveyLevelClassifyRequest(BaseModel):
    """Batch classify uploads using the local exemplar corpus (``knowledge_base_dirs``)."""

    document_ids: list[str] = Field(..., min_length=1, max_length=80)
    force_refresh_corpus: bool = Field(
        default=False,
        description="Rebuild cached corpus profiles from disk before scoring.",
    )

    @field_validator("document_ids")
    @classmethod
    def _dedupe_ids(cls, v: list[str]) -> list[str]:
        seen: set[str] = set()
        out: list[str] = []
        for x in v:
            s = str(x).strip()
            if not s or s in seen:
                continue
            seen.add(s)
            out.append(s)
        if not out:
            raise ValueError("document_ids must contain at least one unique id")
        return out


class SurveyLevelClassifyResponse(BaseModel):
    """Classifier output for each requested document."""

    items: list[SurveyLevelClassificationItem]
    corpus_labelled_files: int = Field(
        default=0,
        description="Exemplar KB files used to build lexical profiles (inferred tier per file).",
    )


class SurveyLevelApplyItem(BaseModel):
    """Confirm a single document's RICS product tier after user review."""

    document_id: str
    survey_level: int = Field(ge=1, le=3)


class SurveyLevelApplyRequest(BaseModel):
    """Persist confirmed tiers — same effect as repeated PATCH /documents/{id}/survey-level."""

    items: list[SurveyLevelApplyItem] = Field(..., min_length=1, max_length=80)


class SurveyLevelApplyResponse(BaseModel):
    """Rows updated; ingestion is not restarted (DB column drives retrieval filtering)."""

    updated: list[DocumentSurveyLevelResponse]


class SurveyLevelCorpusRefreshRequest(BaseModel):
    """Optional body for corpus profile rebuild."""

    force: bool = Field(default=True, description="When true, ignore TTL and rebuild from disk.")


class SurveyLevelCorpusRefreshResponse(BaseModel):
    """Observability after rebuilding cached corpus statistics."""

    files_used: int
    created_at_unix: int


class TemplateCatalogSection(BaseModel):
    """One row in the UI section list for a given RICS product tier."""

    code: str
    title: str
    group: str
    hint: str = Field(default="", description="Short prompt for inspection notes (derived from expected fields)")


class TemplateCatalogResponse(BaseModel):
    """Full section manifest for configuring generation — depends on survey product level."""

    survey_level: int = Field(ge=1, le=3)
    product_name: str
    docx_title: str
    sections: list[TemplateCatalogSection]
    group_labels: dict[str, str]


class BatchUploadItem(BaseModel):
    """One row from a bulk upload: accepted into the DB or rejected with a reason."""

    document_id: str | None = None
    filename: str
    status: str = Field(description="accepted | rejected")
    message: str = ""


class BulkUploadResponse(BaseModel):
    """Response from POST /upload/batch — each file is stored as its own ``Document`` row."""

    tenant_id: str
    accepted: int
    rejected: int
    items: list[BatchUploadItem]
    message: str = ""


class DocumentBatchStatusRequest(BaseModel):
    """Body for POST /documents/batch-status."""

    document_ids: list[str] = Field(
        ...,
        description="Document UUIDs to query (must belong to the authenticated tenant)",
    )

    @field_validator("document_ids")
    @classmethod
    def _cap_id_count(cls, v: list[str]) -> list[str]:
        from app.config import settings

        cap = settings.max_batch_status_document_ids
        if len(v) > cap:
            raise ValueError(f"Too many document_ids (max {cap})")
        return v


class DocumentStatusItem(BaseModel):
    document_id: str
    status: str
    filename: str = ""
    error: str | None = None


class DocumentBatchStatusResponse(BaseModel):
    """Aggregated ingestion status for many documents in one round-trip."""

    items: list[DocumentStatusItem]
    pending: int
    processing: int
    complete: int
    failed: int


# ── Parsed document structure ─────────────────────────────────────────────────

class ParsedBlock(BaseModel):
    """A single structural block extracted from a document.

    Example::

        ParsedBlock(block_type="heading", text="1. Location", level=1, page=1)
    """

    block_type: str = Field(
        description="One of: heading | paragraph | list_item | table_cell"
    )
    text: str
    level: int = Field(default=0, description="Heading depth; 0 for non-headings")
    page: int = Field(default=0, description="1-based page number (PDF only)")


# ── Chunks ────────────────────────────────────────────────────────────────────

class Chunk(BaseModel):
    """An embedding-ready text chunk with full provenance metadata.

    Example::

        Chunk(
            chunk_id="c-001", doc_id="d-abc", tenant_id="t-xyz",
            text="The property is a semi-detached...", section_type="paragraph",
            token_count=87,
        )
    """

    chunk_id: str
    doc_id: str
    tenant_id: str
    text: str
    section_type: str = Field(default="paragraph")
    token_count: int = Field(default=0)
    created_at: datetime = Field(default_factory=lambda: datetime.now(UTC))


class ChunkMetadata(BaseModel):
    """Subset of Chunk stored as FAISS / LangChain document metadata."""

    chunk_id: str
    doc_id: str
    tenant_id: str
    section_type: str
    token_count: int
    created_at: str


# ── Retrieval ─────────────────────────────────────────────────────────────────

class SearchResult(BaseModel):
    """A single vector-store hit returned by the retriever."""

    chunk_id: str
    doc_id: str
    tenant_id: str
    text: str
    score: float
    section_type: str
    hierarchy_level: str = Field(
        default="paragraph",
        description="document | section | paragraph (hierarchical RAG)",
    )
    section_title: str | None = Field(default=None, description="Heading / page label when known")
    section_id: str | None = Field(default=None, description="Stable section key within the upload")
    paragraph_index: int | None = Field(default=None, description="Index within the section for paragraph rows")
    parent_chunk_id: str | None = Field(
        default=None,
        description="Optional link to parent row (reserved for future graph edges)",
    )
    source: str | None = Field(
        default=None,
        description="Optional source label (e.g. original filename when not in DB, such as knowledge base).",
    )
    kb: bool | None = Field(
        default=None,
        description="True when this chunk comes from the local knowledge base corpus.",
    )
    kb_path: str | None = Field(
        default=None,
        description="Optional file path for knowledge base chunks (best-effort; for debugging only).",
    )
    chunk_role: str | None = Field(
        default=None,
        description="boilerplate | reference | exemplar — used to bias retrieval at assembly tier.",
    )


class RerankedResult(SearchResult):
    """A retrieval result after lexical / numeric reranking."""

    rerank_score: float = 0.0


# ── Generation ────────────────────────────────────────────────────────────────

class Provenance(BaseModel):
    """Source attribution for a single retrieved snippet."""

    doc_id: str
    chunk_id: str
    score: float
    filename: str | None = Field(
        default=None,
        description="Original upload filename for doc_id (when resolved)",
    )
    snippet_preview: str | None = Field(
        default=None,
        description="Short excerpt from the retrieved chunk for UI citations",
    )
    section_hint: str | None = Field(
        default=None,
        description="Best-effort heading or chunk label for citation display",
    )


class SectionPhotoItem(BaseModel):
    """Metadata for one uploaded photo attached to a report section."""

    photo_id: str
    original_filename: str
    content_type: str
    created_at: str
    url: str


class SectionPayload(BaseModel):
    """Frontend-facing payload for a single generated report section."""

    text: str
    confidence: float
    provenance: list[Provenance]
    cached: bool = False
    mode: str = Field(default="generate", description="Mode used: generate | proofread | enhance")
    style_profile: WritingStyleProfile | None = Field(
        default=None, description="Style profile applied during generation"
    )
    ai_level: int | None = Field(
        default=None,
        description="AI interference level 1–5 used for this section",
    )
    ai_percent: int | None = Field(
        default=None,
        description="AI involvement intensity 0–100 (preferred control; overrides ai_level when provided)",
    )
    ai_transparency: dict[str, Any] | None = Field(
        default=None,
        description="Estimated AI involvement breakdown and plain-language explanation",
    )
    photos: list[SectionPhotoItem] = Field(
        default_factory=list,
        description="Uploaded photos attached to this section (for evidence and DOCX export).",
    )
    pipeline: str | None = Field(
        default=None,
        description="Generation pipeline used: agentic | standard (when available).",
    )
    fallback_used: bool | None = Field(
        default=None,
        description="True when the primary pipeline failed and the section was generated via fallback.",
    )
    inspector: dict[str, Any] | None = Field(
        default=None,
        description=(
            "When ``pipeline`` is ``agentic``, structured outputs from the OpenAI inspector "
            "tool loop (extraction audit, section plan, condition rating summary, truncated tool trace)."
        ),
    )
    interference_level: str | None = Field(
        default=None,
        description="AI interference mode used for this section: minimum | medium | maximum.",
    )
    word_count: int | None = Field(
        default=None,
        description="Approximate word count of the section body at last generation.",
    )
    generated_at: str | None = Field(
        default=None,
        description="ISO 8601 UTC timestamp when this section was last generated or updated by AI.",
    )


class AILevel(int, Enum):
    """User-controlled AI interference level (1 = RAG only, 5 = Full AI)."""
    rag_only = 1
    """Pure retrieval: the LLM does minimal prose rewriting; text closely mirrors source chunks."""
    light = 2
    """Light touch: minor phrasing improvements, facts preserved verbatim."""
    balanced = 3
    """Default: RAG evidence + moderate style adaptation to the user's voice."""
    strong = 4
    """Strong AI: richer paraphrasing, deeper style matching, more creative bridging."""
    full_ai = 5
    """Full AI: maximum style optimisation, most creative prose; unknowns must be stated as missing/ unverifiable."""


def ai_level_to_percent(ai_level: int) -> int:
    """Map the legacy 1–5 scale to a 0–100 intensity."""
    level = max(1, min(5, int(ai_level)))
    return int((level - 1) * 25)


def ai_percent_to_level(ai_percent: int) -> int:
    """Map a 0–100 intensity to the legacy 1–5 scale (for backward compatibility)."""
    p = max(0, min(100, int(ai_percent)))
    # 0..24 -> 1, 25..49 -> 2, 50..74 -> 3, 75..99 -> 4, 100 -> 5
    return min(5, (p // 25) + 1)


class RetrievalLevel(StrEnum):
    """User-selected retrieval granularity for hierarchical RAG."""

    document = "document"
    """Use document-level embeddings only (whole-file intent / holistic context)."""

    section = "section"
    """Use section-level embeddings only (mid-granularity scope, e.g. page/part)."""

    paragraph = "paragraph"
    """Use paragraph/chunk-level embeddings only (fine-grained, precise evidence)."""


class InterferenceLevel(StrEnum):
    """Qualitative AI interference selector (maps to fixed internal ``ai_percent`` bands)."""

    minimum = "minimum"
    """Strict formatter: map notes onto standard structure with almost no invention."""

    medium = "medium"
    """Professional editor: light inference and bridging, traceable to notes."""

    maximum = "maximum"
    """Expert report writer: full prose within anti-hallucination constraints."""


INTERFERENCE_LEVEL_AI_PERCENT: dict[InterferenceLevel, int] = {
    InterferenceLevel.minimum: 8,
    InterferenceLevel.medium: 52,
    InterferenceLevel.maximum: 93,
}


class GenerateRequest(BaseModel):
    """Request body for POST /reports/{report_id}/generate.

    Example::

        GenerateRequest(
            template_id="D",
            bullets=["Semi-detached house, circa 1965", "Floor area 95 sqm"],
            mode=GenerationMode.generate,
            ai_level=3,
        )
    """

    template_id: str = Field(description="RICS section code, e.g. D, E2, E4, G4")
    bullets: list[str] = Field(
        description="Inspector messy notes / fact bullets (primary factual source for this section).",
        max_length=5000,
    )
    messy_notes: list[str] | None = Field(
        default=None,
        description=(
            "Optional alias for ``bullets``: same content as raw inspector notes. "
            "When ``bullets`` is empty and this is provided, it is copied into ``bullets`` before validation."
        ),
    )
    mode: GenerationMode = Field(
        default=GenerationMode.generate,
        description="generate | proofread | enhance",
    )
    ai_percent: int | None = Field(
        default=50,
        ge=0,
        le=100,
        description=(
            "AI involvement slider value (0–100). "
            "0 = pure RAG/no rewriting; 100 = maximum style optimisation. "
            "Preferred over ai_level when ``ai_involvement_tier`` is not set."
        ),
    )
    interference_level: InterferenceLevel | None = Field(
        default=None,
        description=(
            "AI interference level: minimum | medium | maximum. When set, overrides "
            "``ai_percent`` and ``ai_level`` for prompts, word targets, and token budgets. "
            "Omit to use legacy ``ai_percent`` / ``ai_level`` only."
        ),
    )
    ai_involvement_tier: str | None = Field(
        default=None,
        description="Deprecated. Use ``interference_level`` (minimum|medium|maximum). Legacy ``minimal`` maps to ``minimum``.",
        exclude=True,
    )
    ai_level: AILevel | None = Field(
        default=AILevel.balanced,
        description=(
            "Legacy AI interference level 1–5 (deprecated in favour of ai_percent). "
            "If both ai_percent and ai_level are provided, ai_percent wins."
        ),
    )
    retrieval_level: RetrievalLevel = Field(
        default=RetrievalLevel.paragraph,
        description=(
            "Hierarchical RAG retrieval granularity: document | section | paragraph. "
            "The backend will retrieve and generate strictly from this level only."
        ),
    )
    force_regenerate: bool = Field(
        default=False,
        description="Skip cache and force a fresh LLM call",
    )
    strict_uploaded_only: bool = Field(
        default=False,
        description=(
            "Hard isolation mode. When true: use ONLY documents explicitly attached to this report "
            "(primary_document_id + reference_document_ids + runtime index), and the current bullets. "
            "Do not use KB/Behrang corpora, do not use the standard-paragraph Word boilerplate, and "
            "avoid tenant-wide style/profile reuse."
        ),
    )
    reference_document_ids: list[str] = Field(
        default_factory=list,
        description=(
            "UUIDs of additional indexed PDFs/DOCX to prioritise after the report's primary upload "
            "(e.g. exemplar RICS reports such as a Beh Rang–style reference). "
            "These act as contextual ``uploaded_reports`` for retrieval alongside the primary document."
        ),
    )
    draft_paragraph: str | None = Field(
        default=None,
        max_length=5000,
        description=(
            "Optional paragraph the surveyor has drafted or edited; the model may mirror its tone, "
            "rhythm, and structure while keeping facts grounded in bullets and retrieved evidence."
        ),
    )
    template_ids: list[str] | None = Field(
        default=None,
        max_length=64,
        description=(
            "Optional extra section codes to process in the same background job "
            "(generate, proofread, or enhance). Parallel when ENABLE_ASYNC_PIPELINE=true, "
            "otherwise sequential. ``template_id`` is always included."
        ),
    )
    bullets_by_section: dict[str, list[str]] | None = Field(
        default=None,
        description=(
            "Per-section bullets when generating multiple sections via ``template_ids``. "
            "Sections omitted here reuse the top-level ``bullets`` list."
        ),
    )

    @model_validator(mode="before")
    @classmethod
    def _merge_aliases_and_interference_level(cls, data: Any) -> Any:
        if not isinstance(data, dict):
            return data
        d = dict(data)
        # Optional alias: messy_notes → bullets when bullets omitted
        bullets = d.get("bullets")
        if (not bullets) and d.get("messy_notes") is not None:
            mn = d["messy_notes"]
            if isinstance(mn, list):
                d["bullets"] = [str(x).strip() for x in mn if str(x).strip()]
            elif isinstance(mn, str):
                d["bullets"] = [x.strip() for x in mn.splitlines() if x.strip()]
        # Legacy ai_involvement_tier → interference_level
        if d.get("interference_level") is None and d.get("ai_involvement_tier") is not None:
            leg = str(d.get("ai_involvement_tier")).strip().lower()
            if leg == "minimal":
                leg = "minimum"
            d["interference_level"] = leg
        raw_il = d.get("interference_level")
        if raw_il is None:
            return d
        try:
            tier = raw_il if isinstance(raw_il, InterferenceLevel) else InterferenceLevel(str(raw_il).strip().lower())
        except Exception as exc:  # noqa: BLE001
            raise ValueError(
                "interference_level must be exactly one of: minimum, medium, maximum."
            ) from exc
        pct = INTERFERENCE_LEVEL_AI_PERCENT[tier]
        return {**d, "ai_percent": pct, "ai_level": ai_percent_to_level(pct)}

    @field_validator("bullets", mode="before")
    @classmethod
    def _normalise_bullets(cls, v: object) -> list[str]:
        # Accept empty lists (the UI may intentionally omit bullets so the user
        # can fill missing sections after generation). We do not hard-fail here
        # because the backend may choose to persist a blank section instead.
        if v is None:
            return []
        if isinstance(v, str):
            # Defensive: allow a newline-joined string payload.
            raw = [x.strip() for x in v.splitlines()]
        elif isinstance(v, list):
            raw = [str(x).strip() for x in v]
        else:
            return []
        # Remove empty items but do NOT enforce a strict max here; the service
        # layer will clamp/dedupe to its operational limit and can surface a
        # user-friendly warning in the UI if desired.
        return [x for x in raw if x]

    @field_validator("reference_document_ids", mode="before")
    @classmethod
    def _normalise_reference_document_ids(cls, v: object) -> list[str]:
        if v is None:
            return []
        if not isinstance(v, list):
            return []
        return [str(x).strip() for x in v if str(x).strip()]

    @field_validator("ai_percent", mode="before")
    @classmethod
    def _normalise_ai_percent(cls, v: object) -> int | None:
        if v is None:
            return None
        try:
            p = int(v)  # allow numeric strings
        except Exception:  # noqa: BLE001
            return None
        return max(0, min(100, p))

    @field_validator("ai_level", mode="before")
    @classmethod
    def _normalise_ai_level(cls, v: object) -> AILevel | None:
        if v is None:
            return None
        try:
            level = int(v)
        except Exception:  # noqa: BLE001
            return None
        level = max(1, min(5, level))
        return AILevel(level)

    @field_validator("ai_level")
    @classmethod
    def _coerce_ai_level_when_percent_missing(cls, v: AILevel | None, info: Any) -> AILevel:
        # If ai_percent was explicitly set (including 0), we keep ai_level as-is
        # and let the service treat ai_percent as the source of truth.
        data = getattr(info, "data", {}) or {}
        if data.get("ai_percent", None) is None:
            # ai_percent missing → ensure ai_level has a sensible default
            return v or AILevel.balanced
        return v or AILevel(ai_percent_to_level(int(data["ai_percent"])))

    @field_validator("draft_paragraph")
    @classmethod
    def _normalise_draft_paragraph(cls, v: str | None) -> str | None:
        if v is None:
            return None
        s = v.strip()
        return s if s else None

    @field_validator("bullets")
    @classmethod
    def _validate_bullets(cls, v: list[str]) -> list[str]:
        """Validate bullets (may be empty).

        Empty bullets are allowed because generation can intentionally persist a
        blank section (see `app/services/generation.py`), enabling the UI to
        prompt the user to fill missing sections inline.
        """
        oversized = [i for i, b in enumerate(v) if len(b) > 2000]
        if oversized:
            raise ValueError(
                f"Bullet(s) at index {oversized} exceed 2000 characters. "
                "Split long notes into shorter bullets."
            )
        return v

    @field_validator("template_id")
    @classmethod
    def _require_valid_template_id(cls, v: str) -> str:
        from app.templates.registry import ALL_VALID_SECTION_CODES

        code = v.strip()
        if not code:
            raise ValueError("template_id must not be blank.")
        if code not in ALL_VALID_SECTION_CODES:
            valid = ", ".join(sorted(ALL_VALID_SECTION_CODES))
            raise ValueError(
                f"template_id {code!r} is not a valid RICS section code "
                f"(depends on survey product tier 1/2/3). Known codes across all tiers: {valid}"
            )
        return code


class ExtractNotesResponse(BaseModel):
    """Response from POST /extract-notes — parsed raw text lines from an uploaded doc.

    Also reports the survey tier the *content* of the notes appears to come from,
    so the frontend can warn when the user has uploaded e.g. Level 3 inspection
    detail onto a Level 1 report (where it would otherwise be silently misrouted
    into the Introduction section).
    """

    filename: str
    lines: list[str]
    line_count: int
    # Tier the notes content reads as. 0 means the classifier had insufficient signal
    # (typically very short notes) — frontend should treat 0 as "unknown" and skip
    # the mismatch modal rather than surface a meaningless warning.
    predicted_survey_level: int = Field(0, ge=0, le=3)
    confidence: float = Field(0.0, ge=0.0, le=1.0)
    rationale: str = ""


class GenerateResponse(BaseModel):
    report_id: str
    status: str
    message: str
    workflow_id: str | None = Field(
        default=None,
        description="Temporal workflow id when ENABLE_TEMPORAL_WORKFLOW=true and start succeeded.",
    )


class RuntimeRagSyncBody(BaseModel):
    """Body for POST /reports/{report_id}/rag/runtime/sync — push edited text into the index."""

    section_code: str = Field(description="RICS section code, same as template_id / generate.template_id")
    text: str = Field(description="Edited section body; becomes source of truth for retrieval")
    section_title: str | None = Field(
        default=None,
        description="Optional label for overview metadata (defaults to section_code)",
    )

    @field_validator("section_code")
    @classmethod
    def _valid_section_code(cls, v: str) -> str:
        from app.templates.registry import ALL_VALID_SECTION_CODES

        code = v.strip()
        if not code:
            raise ValueError("section_code must not be blank.")
        if code not in ALL_VALID_SECTION_CODES:
            valid = ", ".join(sorted(ALL_VALID_SECTION_CODES))
            raise ValueError(
                f"section_code {code!r} is not a valid RICS section code across product tiers. Valid codes: {valid}"
            )
        return code


class RuntimeRagSyncResponse(BaseModel):
    """Result of a runtime RAG re-index operation."""

    virtual_doc_id: str
    chunks_indexed: int


class ReportStatusResponse(BaseModel):
    report_id: str
    status: str
    created_at: datetime
    updated_at: datetime
    error_message: str | None = None
    survey_level: int | None = Field(
        default=None,
        description="RICS Home Survey product tier used for this report job (1 / 2 / 3).",
    )


class SectionsResponse(BaseModel):
    report_id: str
    sections: dict[str, SectionPayload]


# Hard cap for inline-edited section bodies.
# Counted in UTF-8 bytes (not characters) so multibyte text is bounded too.
SECTION_TEXT_MAX_BYTES: int = 200 * 1024  # 200 KB


class SectionTextUpdateBody(BaseModel):
    """Body for ``PATCH /reports/{report_id}/sections/{section_code}``.

    Persists an inline-edited section body. Empty string is accepted (the user
    may want to clear the section). The 200 KB cap is enforced **inside the
    endpoint** rather than as a Pydantic ``max_length`` constraint so we can
    return HTTP 413 (Payload Too Large) instead of Pydantic's default 422.

    Note: This body has exactly one field. Do not add new fields here without
    a paired backend change in ``update_section_text``.
    """

    text: str = Field(
        ...,
        description=(
            "New section body (UTF-8 string; empty string is allowed to clear the section). "
            f"The endpoint rejects bodies whose UTF-8 byte length exceeds {SECTION_TEXT_MAX_BYTES} bytes "
            "(200 KB) with HTTP 413."
        ),
    )


# ── Style profile endpoint ───────────────────────────────────────────────────

class StyleProfileResponse(BaseModel):
    """Response for GET /tenants/{tenant_id}/style-profile."""

    tenant_id: str
    profile: WritingStyleProfile
    analysed_at: datetime = Field(default_factory=lambda: datetime.now(UTC))


# ── Similarity / deduplication (notes vs library & other sections) ────────────


class SimilarContentRequest(BaseModel):
    """Body for POST /content/similar — find overlapping uploads and draft notes."""

    text: str = Field(..., max_length=50_000, description="Paragraph or bullet block to check")
    section_code: str | None = Field(
        default=None,
        description="Current RICS section code (excluded from peer overlap scan)",
    )
    limit: int = Field(default=8, ge=1, le=20, description="Max library matches to return")
    min_relevance_percent: float = Field(
        default=28.0,
        ge=0.0,
        le=100.0,
        description="Drop library hits weaker than this %% of the strongest match in the batch",
    )
    peer_sections: dict[str, str] = Field(
        default_factory=dict,
        description="Other sections' draft notes: section_code → bullets text (for duplicate detection)",
    )
    exclude_document_ids: list[str] = Field(
        default_factory=list,
        description=(
            "Omit these uploaded document UUIDs from library matches — e.g. the primary survey file "
            "so results highlight separate guidance / regulation uploads"
        ),
    )

    @field_validator("exclude_document_ids")
    @classmethod
    def _normalize_exclude_ids(cls, v: list[str]) -> list[str]:
        if len(v) > 48:
            raise ValueError("exclude_document_ids: at most 48 entries")
        return [x.strip() for x in v if x.strip()]


class LibrarySimilarMatch(BaseModel):
    """A chunk from the tenant's indexed uploads that is semantically close to the query text."""

    chunk_id: str
    document_id: str
    filename: str | None = None
    snippet: str = Field(description="Short excerpt from the indexed document")
    relevance_percent: float = Field(description="0–100, relative to strongest hit in this response")
    section_type: str = "paragraph"


class DraftOverlapMatch(BaseModel):
    """Another section's notes (or a line within them) that overlaps the submitted text."""

    other_section_code: str
    overlap_kind: str = Field(description="line | block")
    similarity: float = Field(ge=0.0, le=1.0, description="Lexical similarity (Jaccard on tokens)")
    your_preview: str = Field(description="The line or excerpt from your current text")
    other_preview: str = Field(description="Matching line or excerpt from the other section")


class SimilarContentResponse(BaseModel):
    """Similarity scan results for informed deduplication / refresh decisions."""

    library_matches: list[LibrarySimilarMatch]
    draft_overlaps: list[DraftOverlapMatch]
    message: str = ""


# ── Canonical paragraph rollout (library-wide semantic upgrade) ───────────────


class CanonicalRolloutRequest(BaseModel):
    """Body for POST /content/canonical-scan — find indexed chunks to upgrade."""

    canonical_text: str = Field(
        ...,
        max_length=50_000,
        description="Improved standard paragraph to match against the tenant index",
    )
    limit: int = Field(default=24, ge=1, le=100, description="Max candidate chunks after filters")
    min_relevance_percent: float = Field(
        default=28.0,
        ge=0.0,
        le=100.0,
        description="Relative to strongest hit in the batch (same idea as /content/similar)",
    )
    min_jaccard_vs_canonical: float = Field(
        default=0.06,
        ge=0.0,
        le=1.0,
        description="Minimum token Jaccard between chunk text and canonical (reduces false positives)",
    )
    document_ids: list[str] | None = Field(
        default=None,
        description="If set, only consider chunks from these uploaded document UUIDs",
    )
    exclude_document_ids: list[str] = Field(
        default_factory=list,
        description="Exclude these document UUIDs from results",
    )
    adapt_with_llm: bool = Field(
        default=False,
        description="If true and OPENAI_API_KEY is set, merge canonical with doc-specific facts via LLM",
    )

    @field_validator("document_ids")
    @classmethod
    def _scope_document_ids(cls, v: list[str] | None) -> list[str] | None:
        if v is None:
            return None
        if len(v) > 200:
            raise ValueError("document_ids: at most 200 entries")
        return [x.strip() for x in v if x.strip()]

    @field_validator("exclude_document_ids")
    @classmethod
    def _normalize_exclude_rollout(cls, v: list[str]) -> list[str]:
        if len(v) > 200:
            raise ValueError("exclude_document_ids: at most 200 entries")
        return [x.strip() for x in v if x.strip()]


class CanonicalRolloutMatch(BaseModel):
    """One indexed chunk that semantically matches the canonical paragraph."""

    chunk_id: str
    document_id: str
    filename: str | None = None
    original_snippet: str = Field(description="Full chunk text (may be long)")
    relevance_percent: float
    jaccard_vs_canonical: float = Field(ge=0.0, le=1.0)
    compatibility: str = Field(
        description="high | review | low — auto-apply only for high after human policy review",
    )
    proposed_replacement: str
    preservation_note: str = Field(
        default="",
        description="Numbers or phrases in the chunk to preserve if adapting manually",
    )


class CanonicalRolloutResponse(BaseModel):
    """Candidates for upgrading library text to a canonical paragraph."""

    matches: list[CanonicalRolloutMatch]
    message: str = ""


class CanonicalApplyRequest(BaseModel):
    """Body for POST /content/canonical-apply — rewrite one chunk in a .docx and re-ingest."""

    document_id: str
    chunk_id: str
    replacement_text: str = Field(..., max_length=50_000)
    confirm_destructive_docx: bool = Field(
        default=False,
        description="Must be true: apply rebuilds the .docx as plain paragraphs (layout may change)",
    )


class CanonicalApplyResponse(BaseModel):
    """After apply: file updated on disk and vector index refreshed for that document."""

    document_id: str
    chunk_id: str
    filename: str
    detail: str
    chunks_indexed: int


class DocumentDeleteResponse(BaseModel):
    """Confirmation after removing a document from the library."""

    document_id: str
    removed: bool = True
    detail: str = ""


# ── Dev / test endpoints ──────────────────────────────────────────────────────

class TestIngestRequest(BaseModel):
    """Body for POST /test/ingest (dev-only endpoint)."""

    file_path: str = Field(description="Absolute path to a sample file on disk")
    tenant_id: str = Field(default="test_tenant")