package qbitrun

import (
	"io"
	"io/fs"
	"os"
	"path/filepath"
)

type WorkflowDir interface {
	Files() []io.ReadCloser
}

type workflowFiles []io.ReadCloser

func (wf workflowFiles) Files() []io.ReadCloser {
	return wf
}

// OpenDir opens a directory and returns a WorkflowDir.
//
// Set filter to filter out unwanted files.
func OpenDir(dir string, filters ...func(path string, d fs.FileInfo) bool) (WorkflowDir, error) {
	var files []io.ReadCloser
	err := filepath.Walk(dir, func(path string, info fs.FileInfo, err error) error {
		if err != nil {
			return err
		}
		if info.IsDir() {
			return nil
		}
		ok := true
		for _, filter := range filters {
			ok = filter(path, info)
			if !ok {
				break
			}
		}
		if ok {
			file, err := os.Open(path)
			if err != nil {
				return err
			}
			files = append(files, file)
		}
		return nil
	})
	if err != nil {
		return nil, err
	}

	return workflowFiles(files), nil
}

// WorkflowFromReadClosers creates a WorkflowDir from a list of io.ReadCloser.
func WorkflowFromReadClosers(rcs ...io.ReadCloser) WorkflowDir {
	return workflowFiles(rcs)
}

// WorkflowFromReaders creates a WorkflowDir from a list of io.Reader.
//
// If the Reader implements io.ReadCloser, it will be used as is.
// If not, it will be wrapped with io.NopCloser.
func WorkflowFromReaders(readers ...io.Reader) WorkflowDir {
	var rcs []io.ReadCloser
	for _, r := range readers {
		if rc, ok := r.(io.ReadCloser); ok {
			rcs = append(rcs, rc)
		} else {
			rcs = append(rcs, io.NopCloser(r))
		}
	}
	return workflowFiles(rcs)
}