"""首响时长+回复率聚合列(msg_daily_stats / stat_daily_staff 各 3 列)

Revision ID: d9e0f1a2b3c4
Revises: c3d4e5f6a7b8
Create Date: 2026-09-07

数据分析板块批1(A1+A2,2026-09-07):管理层要看「每个人的响应质量」。
两表各加 cust_threads / threads_answered / fr_sum_ms——消息串算法见
app/storage/summary.py(口径与 8-24 spec 对齐,日切近似 v1)。
fr_cnt ≡ threads_answered(被回串数=样本数),不单列。

幂等:sa.inspect 先查列存在则跳过(照 9b0d0c133035 惯例,SQLite/MySQL
通用);downgrade 对称删列。模型侧 models.py 同步双声明,防 alembic
autogenerate 反 DROP。NOT NULL + server_default 0:旧行/旧构造不传也不炸。
"""
from collections.abc import Sequence

import sqlalchemy as sa
from alembic import op


# revision identifiers, used by Alembic.
revision: str = "d9e0f1a2b3c4"
down_revision: str | Sequence[str] | None = "c3d4e5f6a7b8"
branch_labels: str | Sequence[str] | None = None
depends_on: str | Sequence[str] | None = None

_COLUMNS: tuple[tuple[str, str, sa.types.TypeEngine], ...] = (
    ("msg_daily_stats", "cust_threads", sa.Integer()),
    ("msg_daily_stats", "threads_answered", sa.Integer()),
    ("msg_daily_stats", "fr_sum_ms", sa.BigInteger()),
    ("stat_daily_staff", "cust_threads", sa.Integer()),
    ("stat_daily_staff", "threads_answered", sa.Integer()),
    ("stat_daily_staff", "fr_sum_ms", sa.BigInteger()),
)


def _has_column(bind, table: str, column: str) -> bool:
    insp = sa.inspect(bind)
    if not insp.has_table(table):
        return False
    return column in {c["name"] for c in insp.get_columns(table)}


def upgrade() -> None:
    """Upgrade schema."""
    bind = op.get_bind()
    for table, column, type_ in _COLUMNS:
        if _has_column(bind, table, column):
            continue  # 幂等:已加过则跳过
        op.add_column(
            table,
            sa.Column(column, type_, nullable=False, server_default=sa.text("0")),
        )


def downgrade() -> None:
    """Downgrade schema."""
    bind = op.get_bind()
    for table, column, _ in _COLUMNS:
        if _has_column(bind, table, column):
            op.drop_column(table, column)