//go:build linux

package main

import (
	"os"
	"path/filepath"
	"testing"
)

type supply map[string]string

func buildTree(t *testing.T, supplies map[string]supply) string {
	t.Helper()
	root := t.TempDir()
	for name, fields := range supplies {
		dir := filepath.Join(root, name)
		if err := os.MkdirAll(dir, 0o755); err != nil {
			t.Fatal(err)
		}
		for key, value := range fields {
			if err := os.WriteFile(filepath.Join(dir, key), []byte(value+"\n"), 0o644); err != nil {
				t.Fatal(err)
			}
		}
	}
	return root
}

func TestSysfsOnBatteryTable(t *testing.T) {
	cases := []struct {
		name     string
		supplies map[string]supply
		want     bool
	}{
		{"desktop without battery", map[string]supply{"AC": {"type": "Mains", "online": "1"}}, false},
		{"empty tree", map[string]supply{}, false},
		{"laptop discharging", map[string]supply{"BAT0": {"type": "Battery", "status": "Discharging"}, "AC": {"type": "Mains", "online": "0"}}, true},
		{"laptop charging", map[string]supply{"BAT0": {"type": "Battery", "status": "Charging"}, "AC": {"type": "Mains", "online": "1"}}, false},
		{"laptop full on mains", map[string]supply{"BAT0": {"type": "Battery", "status": "Full"}, "AC": {"type": "Mains", "online": "1"}}, false},
		{"discharging but usb-c online", map[string]supply{"BAT0": {"type": "Battery", "status": "Discharging"}, "ucsi": {"type": "USB", "online": "1"}}, false},
		{"discharging usb-c offline", map[string]supply{"BAT0": {"type": "Battery", "status": "Discharging"}, "ucsi": {"type": "USB_C", "online": "0"}}, true},
		{"adp supply online", map[string]supply{"BAT1": {"type": "Battery", "status": "Discharging"}, "ADP1": {"type": "ADP", "online": "1"}}, false},
		{"peripheral battery ignored", map[string]supply{"hid": {"type": "Battery", "status": "Discharging", "scope": "Device"}, "AC": {"type": "Mains", "online": "1"}}, false},
		{"peripheral only", map[string]supply{"hid": {"type": "Battery", "status": "Discharging", "scope": "Device"}}, false},
		{"unknown status", map[string]supply{"BAT0": {"type": "Battery", "status": "Unknown"}}, false},
	}
	for _, item := range cases {
		got, err := sysfsOnBattery(buildTree(t, item.supplies))
		if err != nil || got != item.want {
			t.Errorf("%s: got %v err %v", item.name, got, err)
		}
	}
}

func TestSysfsMissingRootIsAnError(t *testing.T) {
	if _, err := sysfsOnBattery(filepath.Join(t.TempDir(), "nope")); err == nil {
		t.Fatal("expected an error")
	}
}