"""Journal-adapter editorial policy. Not a general provenance or privacy rule.

Fact fidelity is not wording fidelity. Editorial mode is chosen locally, without
a second model call. Historical texts are style references, never today's facts.
"""
from __future__ import annotations

import hashlib
import re
from difflib import SequenceMatcher

from journal_body import plain_text
from writing_profile_schema import is_meta_style_text, recency_weight
from writing_profile_store import (
    clip_field,
    get_profile,
    has_confirmed_profile,
    list_style_sources,
)

PROSE_EDIT = "prose_edit"
NOTES_TO_JOURNAL = "notes_to_journal"
EDITORIAL_MODES = (PROSE_EDIT, NOTES_TO_JOURNAL)

STYLE_EXAMPLE_MAX = 2
STYLE_EXAMPLE_CHARS = 900
MIN_EXAMPLE_CHARS = 40

INSTRUCTIONS = {
    PROSE_EDIT: (
        "Modus prose_edit: Der Rohtext ist bereits erzählerisch. "
        "Gute Formulierungen bewahren. Rechtschreibung, Grammatik und Zeichensetzung "
        "korrigieren. Holprige Stellen glätten, Wiederholungen reduzieren, Absätze und "
        "Übergänge verbessern. Die persönliche Schreibstimme anwenden. "
        "Keine unnötige vollständige Neufassung erzwingen."
    ),
    NOTES_TO_JOURNAL: (
        "Modus notes_to_journal: Die Quellen sind Stichpunkte, Kurztexte oder Fragmente. "
        "Daraus zusammenhängende Journalprosa bilden. Nur sprachlich nötige Verbindungen "
        "herstellen. Keine neuen Tatsachen, Ursachen oder Bewertungen ergänzen. "
        "Die Stichpunkte nicht inklusive ihrer Fehler hintereinanderkopieren."
    ),
}

EMPTY_STYLE_EXAMPLES = (
    "Keine historischen Stilbeispiele. Es gilt nur WRITING_PROFILE "
    "(oder der neutrale Journalstil)."
)


def choose_editorial_mode(user_bodies: list[str]) -> str:
    """MVP mode choice. No classifier model.

    A source block counts as already narrative when it contains `.`, `!` or `?`.
    Mixed default: `prose_edit` when at least half of the non-empty blocks are
    narrative; otherwise `notes_to_journal`.
    """
    blocks = [(item or "").strip() for item in user_bodies if (item or "").strip()]
    if not blocks:
        return NOTES_TO_JOURNAL
    narrative = sum(1 for block in blocks if any(mark in block for mark in ".!?"))
    if narrative * 2 >= len(blocks):
        return PROSE_EDIT
    return NOTES_TO_JOURNAL


def editorial_instructions(mode: str) -> str:
    return INSTRUCTIONS.get(mode) or INSTRUCTIONS[PROSE_EDIT]


def lexical_similarity(left: str, right: str) -> float:
    """Diagnostic only. Must not reject a draft or trigger a retry."""
    a = re.sub(r"\s+", " ", (left or "").strip().lower())
    b = re.sub(r"\s+", " ", (right or "").strip().lower())
    if not a or not b:
        return 0.0
    return round(SequenceMatcher(None, a, b).ratio(), 3)


def narration_sources_text(artifact: dict) -> str:
    """Present attested day facts to the model. Not a wording template, not JSON."""
    parts: list[str] = []
    for item in artifact.get("sources") or []:
        if not isinstance(item, dict):
            continue
        text = (item.get("text") or "").strip()
        if not text:
            continue
        source_id = (item.get("source_id") or "").strip()
        prefix = f"[{source_id}]\n" if source_id else ""
        parts.append(prefix + text)
    if parts:
        return "\n\n".join(parts)
    from journal_reconstruct import claim_texts

    fallback = [str(part).strip() for part in claim_texts(artifact) if str(part).strip()]
    return "\n\n".join(fallback)


def format_style_examples(examples: list[dict]) -> str:
    if not examples:
        return EMPTY_STYLE_EXAMPLES
    lines = [
        "Nur Ton, Rhythmus und sprachliche Entscheidungen. "
        "Ereignisse, Personen, Orte und Bewertungen aus diesen Beispielen "
        "sind keine Tatsachen des heutigen Eintrags und dürfen nicht übernommen werden."
    ]
    for index, item in enumerate(examples, start=1):
        kind = item.get("kind") or "style"
        when = (item.get("occurred_at") or "")[:10]
        header = f"Beispiel {index} ({kind}" + (f", {when}" if when else "") + "):"
        lines.append(header)
        lines.append((item.get("excerpt") or "").strip())
    return "\n".join(part for part in lines if part).strip()


def _content_digest(text: str) -> str:
    body = re.sub(r"\s+", " ", plain_text(text or "")).strip().lower()
    return hashlib.sha256(body.encode("utf-8")).hexdigest()


def _eligible_excerpt(body: str, limit: int) -> str:
    text = plain_text(body or "").strip()
    if len(text) < MIN_EXAMPLE_CHARS or is_meta_style_text(text):
        return ""
    return clip_field(text, limit)


def select_journal_style_examples(
    profile_id: str,
    *,
    exclude_dates: list[str] | None = None,
    exclude_entry_ids: list[str] | None = None,
    max_n: int = STYLE_EXAMPLE_MAX,
    max_chars: int = STYLE_EXAMPLE_CHARS,
) -> list[dict]:
    """Final accepted journal texts first, then imports, then trait excerpts.

    Current-day sources are excluded. Dialogue is never a style authority.
    """
    excluded_dates = {(item or "")[:10] for item in (exclude_dates or []) if item}
    excluded_ids = {item for item in (exclude_entry_ids or []) if item}
    ranked = list_style_sources(profile_id)
    buckets = [
        ("journal_entry", ranked.get("journal_entry") or []),
        ("imported_text", ranked.get("imported_text") or []),
    ]
    picked: list[dict] = []
    seen: set[str] = set()

    def consider(kind: str, item: dict, excerpt: str) -> None:
        if len(picked) >= max_n or not excerpt:
            return
        digest = _content_digest(excerpt)
        if digest in seen:
            return
        seen.add(digest)
        picked.append(
            {
                "kind": kind,
                "excerpt": excerpt,
                "occurred_at": item.get("occurred_at") or item.get("created"),
                "entry_id": item.get("entry_id"),
                "weight": item.get("weight") or recency_weight(item.get("occurred_at")),
            }
        )

    for kind, rows in buckets:
        ordered = sorted(
            rows,
            key=lambda row: (
                -float(row.get("weight") or 0),
                -recency_weight(row.get("occurred_at") or row.get("created")),
            ),
        )
        for item in ordered:
            if len(picked) >= max_n:
                return picked
            entry_id = (item.get("entry_id") or "").strip()
            if entry_id and entry_id in excluded_ids:
                continue
            when = (item.get("occurred_at") or "")[:10]
            if when and when in excluded_dates:
                continue
            consider(kind, item, _eligible_excerpt(item.get("body") or "", max_chars))

    if picked:
        return picked

    profile = get_profile(profile_id)
    if not has_confirmed_profile(profile_id):
        return picked
    for trait in profile.get("traits") or []:
        if len(picked) >= max_n:
            break
        for ref in trait.get("exemplars") or []:
            excerpt = _eligible_excerpt(ref.get("excerpt") or "", max_chars)
            consider("trait_exemplar", ref, excerpt)
            if len(picked) >= max_n:
                break
    return picked