package miner

import (
	"os/exec"
	"strings"
)

var (
	containerLookPathFn = exec.LookPath
	containerVersionCmd = func(path string, args ...string) *exec.Cmd {
		return exec.Command(path, args...)
	}
)

// SetContainerRuntimeProbes injects lookPath/version probes for tests; pass nil to restore defaults.
func SetContainerRuntimeProbes(
	lookPath func(string) (string, error),
	versionCmd func(string, ...string) *exec.Cmd,
) {
	if lookPath == nil {
		containerLookPathFn = exec.LookPath
	} else {
		containerLookPathFn = lookPath
	}
	if versionCmd == nil {
		containerVersionCmd = func(path string, args ...string) *exec.Cmd {
			return exec.Command(path, args...)
		}
	} else {
		containerVersionCmd = versionCmd
	}
}

// DetectContainerRuntime probes docker then podman CLIs.
func DetectContainerRuntime() ContainerRuntimeInfo {
	for _, cli := range []string{"docker", "podman"} {
		if path, err := containerLookPathFn(cli); err == nil {
			out, runErr := containerVersionCmd(path, "version", "--format", "{{.Server.Version}}").CombinedOutput()
			version := strings.TrimSpace(string(out))
			if runErr != nil || version == "" {
				// Older docker without --format still counts as available.
				if _, verErr := containerVersionCmd(path, "version").CombinedOutput(); verErr == nil {
					return ContainerRuntimeInfo{Available: true, CLI: cli, Version: "unknown"}
				}
				continue
			}
			return ContainerRuntimeInfo{Available: true, CLI: cli, Version: version}
		}
	}
	return ContainerRuntimeInfo{}
}