"""迁移 026：用户产品小册子资料库与海报产品来源快照。"""
import logging

from sqlalchemy import inspect, text

logger = logging.getLogger(__name__)


def _primary_key_sql(dialect: str) -> str:
    if dialect == "postgresql":
        return "BIGSERIAL PRIMARY KEY"
    if dialect in ("mysql", "mariadb"):
        return "BIGINT AUTO_INCREMENT PRIMARY KEY"
    return "INTEGER PRIMARY KEY AUTOINCREMENT"


def _column_names(db, table_name: str) -> set[str]:
    return {item["name"] for item in inspect(db.engine).get_columns(table_name)}


def _index_names(db, table_name: str) -> set[str]:
    return {item["name"] for item in inspect(db.engine).get_indexes(table_name)}


def migrate():
    """幂等创建用户资料表并扩展海报关联字段。"""
    from insurance.db.compat import db

    dialect = db.engine.dialect.name
    inspector = inspect(db.engine)
    if not inspector.has_table("insurance_user_product_materials"):
        db.session.execute(text(f"""
            CREATE TABLE insurance_user_product_materials (
                id {_primary_key_sql(dialect)},
                owner_user_id VARCHAR(64) NOT NULL,
                tenant_id VARCHAR(64) NOT NULL DEFAULT 'default',
                company_id VARCHAR(50),
                company_name VARCHAR(100),
                product_name VARCHAR(150),
                plan_type VARCHAR(20),
                original_name VARCHAR(200) NOT NULL,
                file_key VARCHAR(500) NOT NULL,
                file_size BIGINT NOT NULL DEFAULT 0,
                page_count INTEGER,
                sha256 VARCHAR(64) NOT NULL,
                parse_status VARCHAR(20) NOT NULL DEFAULT 'pending',
                parse_message VARCHAR(500) NOT NULL DEFAULT '',
                parse_error TEXT,
                parse_task_id VARCHAR(200),
                parse_started_at TIMESTAMP,
                parse_finished_at TIMESTAMP,
                parsed_rules TEXT,
                confirmed_rules TEXT,
                confirmed_by VARCHAR(64),
                confirmed_at TIMESTAMP,
                review_status VARCHAR(20) NOT NULL DEFAULT 'private',
                status SMALLINT NOT NULL DEFAULT 1,
                deleted_at TIMESTAMP,
                created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP,
                updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
            )
        """))
        db.session.commit()
        logger.info("[migrate_026] 已创建 insurance_user_product_materials")

    desired_indexes = {
        "idx_user_material_owner_updated": "owner_user_id, updated_at",
        "idx_user_material_owner_sha256": "owner_user_id, sha256",
        "idx_user_material_parse_status": "parse_status",
    }
    existing_indexes = _index_names(db, "insurance_user_product_materials")
    for index_name, columns in desired_indexes.items():
        if index_name not in existing_indexes:
            db.session.execute(text(
                f"CREATE INDEX {index_name} "
                f"ON insurance_user_product_materials ({columns})"
            ))

    extra_columns = {
        "product_source_type": "VARCHAR(20)",
        "product_source_id": "VARCHAR(64)",
        "product_snapshot_json": "TEXT",
    }
    for table_name in ("poster_case_uploads", "poster_records"):
        current_columns = _column_names(db, table_name)
        for column_name, column_type in extra_columns.items():
            if column_name not in current_columns:
                db.session.execute(text(
                    f"ALTER TABLE {table_name} ADD COLUMN {column_name} {column_type}"
                ))

        db.session.execute(text(
            f"UPDATE {table_name} "
            "SET product_source_type = 'library_product', product_source_id = product_id "
            "WHERE product_id IS NOT NULL AND product_id <> '' "
            "AND (product_source_type IS NULL OR product_source_type = '')"
        ))

    db.session.commit()
    logger.info("[migrate_026] 用户产品资料库迁移完成")