// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

package conditions

import (
	"context"
	"fmt"
	"os"
	"time"
)

type file string

func (filename file) Wait(ctx context.Context) error {
	for {
		_, err := os.Stat(string(filename))
		if err == nil {
			return nil
		}

		if !os.IsNotExist(err) {
			return err
		}

		select {
		case <-ctx.Done():
			return ctx.Err()
		case <-time.After(1 * time.Second):
		}
	}
}

func (filename file) String() string {
	return fmt.Sprintf("file %q to exist", string(filename))
}

// WaitForFileToExist is a service condition that will wait for the existence of
// a file.
func WaitForFileToExist(filename string) Condition {
	return file(filename)
}

// WaitForFilesToExist is a service condition that will wait for the existence of all the files.
func WaitForFilesToExist(filenames ...string) Condition {
	conditions := make([]Condition, len(filenames))
	for i := range filenames {
		conditions[i] = WaitForFileToExist(filenames[i])
	}

	return WaitForAll(conditions...)
}