package configkit

import "io/fs"

// ResourceContext provides a passive rooted filesystem view and a
// slash-relative BaseDir for one acquired source. FS is borrowed: caller-owned
// filesystems remain under caller control, and host files are opened afresh.
// Querying this record performs no I/O. Resource contents may change after
// loading; callers must close files they open through FS.
type ResourceContext struct {
	FS      fs.FS
	BaseDir string
}

// SourceContext returns the context of an acquired source ID. Unknown IDs and
// sources without context return false. It is nil-safe and performs no I/O.
// Follow individual origin locations when an origin has multiple sources.
func (r *Result[T]) SourceContext(id string) (ResourceContext, bool) {
	if r == nil || r.inspection == nil {
		return ResourceContext{}, false
	}
	context, ok := r.inspection.SourceContext(id)
	return ResourceContext{FS: context.FS, BaseDir: context.BaseDir}, ok
}

// SourceContext returns a passive source context during the active resolution
// callback. Like other Resolution queries, it cannot be used after callback
// return and performs no filesystem operations itself.
func (r *Resolution) SourceContext(id string) (ResourceContext, bool) {
	context, ok := r.engineContext().SourceContext(id)
	return ResourceContext{FS: context.FS, BaseDir: context.BaseDir}, ok
}