package health

import (
	"path/filepath"
	"runtime"
)

// fsKey uniquely identifies a mounted filesystem (dedupe across scan roots).
type fsKey struct {
	typ  int64
	val0 int32
	val1 int32
}

type Snapshot struct {
	UptimeSeconds      int64
	CPUUsagePercent    float64
	MemoryUsagePercent float64
	StorageTotalBytes  uint64
	StorageFreeBytes   uint64
	LibraryFileCount   int
	ActiveStreams      int
	CurrentBytesPerSec int64
	ScanStatus         string
	Errors             []string
}

func MemoryUsagePercent() float64 {
	var m runtime.MemStats
	runtime.ReadMemStats(&m)
	if m.Sys == 0 {
		return 0
	}
	return float64(m.Alloc) / float64(m.Sys) * 100
}

func DiskUsage(paths []string) (total, free uint64) {
	seenPaths := map[string]bool{}
	seenFS := map[fsKey]bool{}
	for _, p := range paths {
		if p == "" {
			continue
		}
		key := filepath.Clean(p)
		if seenPaths[key] {
			continue
		}
		seenPaths[key] = true
		t, f, fsid, ok := diskStat(p)
		if !ok {
			continue
		}
		if seenFS[fsid] {
			continue
		}
		seenFS[fsid] = true
		total += t
		free += f
	}
	return total, free
}