package seriatim

import "context"

// NoopRunner is a deterministic no-op seriatim adapter.
type NoopRunner struct{}

// Run returns the requested output path with placeholder metadata.
func (n *NoopRunner) Run(ctx context.Context, req MergeRequest) (MergeResult, error) {
	if err := ctx.Err(); err != nil {
		return MergeResult{}, err
	}
	return MergeResult{MergedTranscriptPath: req.OutputMergedTranscriptPath, Metadata: map[string]any{"placeholder": true}}, nil
}

// FakeRunner captures merge requests and returns deterministic responses.
type FakeRunner struct {
	Requests []MergeRequest
	Err      error
	Result   MergeResult
}

// Run records request and returns configured response.
func (f *FakeRunner) Run(ctx context.Context, req MergeRequest) (MergeResult, error) {
	if err := ctx.Err(); err != nil {
		return MergeResult{}, err
	}
	f.Requests = append(f.Requests, req)
	if f.Err != nil {
		return MergeResult{}, f.Err
	}
	res := f.Result
	if res.MergedTranscriptPath == "" {
		res.MergedTranscriptPath = req.OutputMergedTranscriptPath
	}
	if res.Metadata == nil {
		res.Metadata = map[string]any{"fake": true}
	}
	return res, nil
}