"""种子数据加载：从 examples/contracts_sample.csv 和 performance_sample.csv 读入。

只在 contracts 表为空时执行，幂等。
真实部署应替换为人事系统 API 调用。
"""

from __future__ import annotations

import csv
import sqlite3
from pathlib import Path

from util.logging_setup import get_skill_logger
from util.runtime_paths import get_examples_dir

logger = get_skill_logger()


def _read_csv(path: Path) -> list[dict[str, str]]:
    with open(path, "r", encoding="utf-8", newline="") as f:
        return list(csv.DictReader(f))


def load_seed_if_empty(conn: sqlite3.Connection) -> tuple[int, int]:
    """如果 contracts 表为空，从 CSV 加载种子数据。返回 (合同数, 业绩数)。"""
    n = conn.execute("SELECT COUNT(*) AS n FROM contracts").fetchone()["n"]
    if n > 0:
        logger.info("seed_data: contracts 表已有 %d 条记录，跳过加载", n)
        return (n, 0)

    examples_dir = get_examples_dir()
    contracts_csv = examples_dir / "contracts_sample.csv"
    performance_csv = examples_dir / "performance_sample.csv"

    if not contracts_csv.exists() or not performance_csv.exists():
        logger.warning("seed_data: 样例 CSV 不存在 %s / %s", contracts_csv, performance_csv)
        return (0, 0)

    contracts = _read_csv(contracts_csv)
    performance = _read_csv(performance_csv)

    with conn:
        conn.executemany(
            """
            INSERT OR REPLACE INTO contracts
                (contract_id, employee_id, teacher_name, unit_id, unit_name,
                 position, contract_type, contract_start, contract_end,
                 trial_period_end, status, last_material_id, renewed_at)
            VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?, ?, NULL, NULL)
            """,
            [
                (
                    c["contract_id"],
                    c["employee_id"],
                    c["teacher_name"],
                    c["unit_id"],
                    c["unit_name"],
                    c["position"],
                    c["contract_type"],
                    c["contract_start"],
                    c["contract_end"],
                    c["trial_period_end"],
                    c["status"],
                )
                for c in contracts
            ],
        )
        conn.executemany(
            """
            INSERT OR REPLACE INTO performance_records
                (record_id, contract_id, year, performance_score,
                 moral_teaching_score, research_score, teaching_score)
            VALUES (?, ?, ?, ?, ?, ?, ?)
            """,
            [
                (
                    p["record_id"],
                    p["contract_id"],
                    int(p["year"]),
                    float(p["performance_score"]),
                    float(p["moral_teaching_score"]),
                    float(p["research_score"]),
                    float(p["teaching_score"]),
                )
                for p in performance
            ],
        )

    logger.info("seed_data: 加载 %d 份合同 / %d 条业绩记录", len(contracts), len(performance))
    return (len(contracts), len(performance))