"""Builds the dynamic per-turn context.

This handles things that change per turn: the current time, today's diary
entries, open tasks. Persona is NOT here; that's a backend configuration
concern (see models/claude_code.py docstring).
"""

import sqlite3
from datetime import datetime, timezone
from pathlib import Path


SENIA_DB = Path("/etc/senia/data/senia.db")


def _today_diary_entries() -> list[str]:
    if not SENIA_DB.exists():
        return []
    now = datetime.now(timezone.utc).astimezone()
    start = now.replace(hour=0, minute=0, second=0, microsecond=0).isoformat()
    conn = sqlite3.connect(SENIA_DB)
    try:
        return [
            f"- {row[0]} - {row[1]}"
            for row in conn.execute(
                "SELECT ts, content FROM diary_logs WHERE ts >= ? ORDER BY ts",
                (start,),
            ).fetchall()
        ]
    finally:
        conn.close()


def build_turn_context(user: str | None = None) -> str:
    diary_entries = _today_diary_entries()
    diary = (
        "\n".join(diary_entries)
        if diary_entries
        else "(no entries yet today)"
    )
    now = datetime.now(timezone.utc).astimezone().isoformat(timespec="seconds")

    time_section = f"## Current time\n{now}\n\n"
    user_section = f"## User\n{user}\n\n" if user else ""
    diary_section = f"## Today's diary so far\n{diary}"

    return f"{time_section}{user_section}{diary_section}"