import java.io.InputStream;
import java.nio.file.Files;
import java.nio.file.Path;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.Statement;
import java.util.Properties;

/**
 * One-off migration: adds b_i18n varchar(150) null to dbo.s_power
 * (i18n resource key for permission point names, see FMS新系统核心表结构设计.md 14.1).
 * Idempotent: skips the ALTER TABLE when the column already exists.
 */
public final class AddSPowerI18nColumn {
    public static void main(String[] args) throws Exception {
        Path apiRoot = Path.of("").toAbsolutePath().normalize();
        Path configPath = apiRoot.resolve("config/dbconfigs/g3hd.properties").normalize();

        Properties properties = new Properties();
        try (InputStream input = Files.newInputStream(configPath)) {
            properties.load(input);
        }

        try (Connection connection = DriverManager.getConnection(
                required(properties, "url"),
                required(properties, "username"),
                required(properties, "password"))) {
            if (!"FMS".equalsIgnoreCase(connection.getCatalog())) {
                throw new IllegalStateException("Refusing to alter database: " + connection.getCatalog());
            }
            try (Statement statement = connection.createStatement()) {
                boolean exists;
                try (ResultSet rows = statement.executeQuery(
                        "SELECT CASE WHEN COL_LENGTH(N'dbo.s_power', N'b_i18n') IS NULL THEN 0 ELSE 1 END")) {
                    rows.next();
                    exists = rows.getInt(1) == 1;
                }
                if (exists) {
                    System.out.println("SKIP|dbo.s_power.b_i18n already exists");
                } else {
                    statement.executeUpdate("ALTER TABLE dbo.s_power ADD b_i18n varchar(150) NULL");
                    System.out.println("APPLIED|ALTER TABLE dbo.s_power ADD b_i18n varchar(150) NULL");
                }
                try (ResultSet rows = statement.executeQuery(
                        "SELECT c.name, t.name, c.max_length, c.is_nullable "
                                + "FROM sys.columns c JOIN sys.types t ON t.user_type_id = c.user_type_id "
                                + "WHERE c.object_id = OBJECT_ID(N'dbo.s_power') AND c.name = N'b_i18n'")) {
                    if (!rows.next()) throw new IllegalStateException("Column b_i18n not found after migration");
                    System.out.println("VERIFY|" + rows.getString(1) + "|" + rows.getString(2)
                            + "(" + rows.getInt(3) + ")|nullable=" + rows.getInt(4));
                }
            }
        }
    }

    private static String required(Properties properties, String key) {
        String value = properties.getProperty(key);
        if (value == null || value.isBlank()) throw new IllegalStateException("Missing property: " + key);
        return value;
    }
}