package nix

import (
	"context"
	"io"
	"iter"
	"os/exec"
)

// Context holds configuration and environment information for interacting with nix.
type Context interface {
	// Streams returns the stdout and stderr writers held by this [Context].
	Streams() (stdout, stderr io.Writer)

	// Nix returns the [exec.Cmd] struct to execute a nix command.
	Nix(ctx context.Context, arg ...string) *exec.Cmd
	// WriteStdin calls [WriteStdin] for [exec.Cmd]. The function f points to is called if [WriteStdin] succeeds.
	WriteStdin(cmd *exec.Cmd, installables iter.Seq[string], f func() error) (int, error)

	// Unwrap returns the stored [context.Context]
	Unwrap() context.Context
}