"""Explicit journal draft generation. Never overwrites the current user entry."""
from __future__ import annotations

from context_builder import assemble_text, build_internal_context
from dialogue_store import StoreError, list_conversations_for_day, list_messages
from engine import execute_prompt, load_active_prompt
from journal_policy import require_explicit_generate, source_conversation_ids
from identity_store import list_mappings
from journal_body import clean_title
from journal_shape import shape_journal
from journal_store import current_draft, current_entries, get_day, insert_draft
from writing_profile_store import compile_style_signals, remember_dialogue_style


def _message_ids(profile_id: str, conversation_ids: list[str]) -> list[str]:
    ids: list[str] = []
    for conversation_id in conversation_ids:
        for message in list_messages(profile_id, conversation_id):
            ids.append(message["id"])
    return ids


def _split_title(content: str) -> tuple[str, str]:
    text = (content or "").strip()
    if not text:
        return "", ""
    lines = text.splitlines()
    title = clean_title(lines[0])
    body = "\n".join(lines[1:]).strip() if len(lines) > 1 else text
    if not title or len(title) > 80:
        return "", text
    return title, body or text


def generate_draft(
    profile_id: str,
    journal_day_id: str,
    conversation_ids: list[str] | None = None,
    include_existing: bool = False,
    explicit: bool = True,
) -> dict:
    require_explicit_generate(explicit)
    day = get_day(profile_id, journal_day_id)
    day_conversations = list_conversations_for_day(profile_id, journal_day_id)
    selected = source_conversation_ids(
        conversation_ids,
        [item["id"] for item in day_conversations],
    )
    remember_dialogue_style(profile_id, exclude_conversation_ids=selected)
    existing_text = ""
    if include_existing:
        draft = current_draft(profile_id, journal_day_id)
        entries = current_entries(profile_id, journal_day_id)
        if draft:
            existing_text = draft.get("body") or ""
        elif entries:
            existing_text = entries[0].get("body") or ""
    context = build_internal_context(
        profile_id,
        space_id=day["space_id"],
        journal_day_id=journal_day_id,
        purpose="journal_generate",
        include_existing=include_existing,
        conversation_ids=selected,
        existing_text=existing_text,
        conversation_id=selected[0] if selected else None,
    )
    assembled = assemble_text(context)
    source_user = [
        message.get("body") or ""
        for conversation_id in selected
        for message in list_messages(profile_id, conversation_id)
        if message.get("role") == "user"
    ]
    signals = compile_style_signals(source_user)
    profile = assembled.get("writing_profile") or ""
    if signals and signals not in profile:
        assembled["writing_profile"] = "\n\n".join(part for part in (profile, signals) if part)
    prompt = load_active_prompt("mvp.journal_generate")
    result = execute_prompt(
        prompt,
        profile_id,
        purpose="journal_generate",
        data_class="B",
        context=assembled,
    )
    title, body = _split_title(result.get("content") or "")
    person_labels = [
        (item.get("local_label") or "").strip()
        for item in list_mappings(profile_id)
        if (item.get("local_label") or "").strip()
        and str(item.get("token") or "").upper().lstrip("[").startswith("PERSON:")
    ]
    title, body = shape_journal(title, body, source_user, person_labels=person_labels)
    before_entries = {item["id"]: item.get("current_version_id") for item in current_entries(profile_id, journal_day_id)}
    draft = insert_draft(
        profile_id,
        journal_day_id,
        title=title,
        body=body,
        source_conversation_ids=selected,
        source_message_ids=_message_ids(profile_id, selected),
    )
    after_entries = current_entries(profile_id, journal_day_id)
    for item in after_entries:
        previous = before_entries.get(item["id"])
        if previous is not None and previous != item.get("current_version_id"):
            raise StoreError("policy_violation", "Generate darf die Nutzerfassung nicht verändern", 500)
    draft["trace"] = result.get("trace")
    return draft