package mysqlite

import (
	"fmt"
	"zombiezen.com/go/sqlite"
)

type Query struct {
	stmt *sqlite.Stmt
	err  error
}

func (d *Db) Query(query string) *Query {
	stmt, remaining, err := d.Db.PrepareTransient(query)
	if err != nil {
		return &Query{err: err}
	}
	if remaining != 0 {
		return &Query{err: fmt.Errorf("remaining bytes: %s", remaining)}
	}
	return &Query{stmt: stmt}
}

//func (q *Query) Args(args ...any) *Query {
//	return q
//}

func (q *Query) Exec() error {
	if q.stmt != nil {
		defer q.stmt.Finalize()
	}
	if q.err != nil {
		return q.err
	}
	rowReturned, err := q.stmt.Step()
	if err != nil {
		return err
	}
	if rowReturned {
		return fmt.Errorf("row returned unexpectedly")
	}
	return err
}

func (q *Query) ScanSingle(results ...any) error {
	if q.stmt != nil {
		defer q.stmt.Finalize()
	}
	if q.err != nil {
		return q.err
	}
	rowReturned, err := q.stmt.Step()
	if err != nil {
		return err
	}
	if !rowReturned {
		return fmt.Errorf("did not return any rows")
	}

	for i, arg := range results {
		if asString, ok := arg.(*string); ok {
			*asString = q.stmt.ColumnText(i)
		} else if asInt, ok := arg.(*int); ok {
			*asInt = q.stmt.ColumnInt(i)
		} else if asBool, ok := arg.(*bool); ok {
			*asBool = q.stmt.ColumnBool(i)
		} else {
			return fmt.Errorf("unsupported column type at index %d", i)
		}
	}
	return nil
}