//! Startup checks the binary owes the database it opens.
//!
//! go-mcp is built from the same source as the desktop app and selects the
//! columns that source assumes, so it has to apply pending migrations itself.
//! Leaving that to the app made every window where the app had not been
//! launched since a migration landed a window where every MCP read failed with
//! a bare `no such column`, mid-session and with no clue attached.

use std::path::Path;

use goingson_db_sqlite::Db;

/// Apply pending migrations, or explain what to run by hand.
///
/// The error names the database and the command that closes the gap, because
/// the failure a caller sees otherwise is a missing column with no context.
pub fn migrate(db: &Db, db_path: &Path) -> Result<(), String> {
    goingson_db_sqlite::run_migrations(db).map_err(|e| {
        format!(
            "could not migrate {path}: {e}\n\
             go-mcp will not serve a database whose schema it does not match.\n\
             Close GoingsOn, back the file up, and run:\n    \
             cargo run -p goingson-db-sqlite --example migrate -- {path}",
            path = db_path.display()
        )
    })
}