package web

import (
	"net/http"
	"strings"
	"syscall"

	"github.com/darroyo/nasctl/internal/system"
)

type diskUsage struct {
	Path        string  `json:"path"`
	TotalBytes  uint64  `json:"total_bytes"`
	FreeBytes   uint64  `json:"free_bytes"`
	UsedBytes   uint64  `json:"used_bytes"`
	UsedPercent float64 `json:"used_percent"`
}

type serviceStatus struct {
	Name   string `json:"name"`
	Active bool   `json:"active"`
	State  string `json:"state"`
}

func (s *Server) handleSystemStatus(w http.ResponseWriter, r *http.Request) {
	status := map[string]any{
		"disks":    collectDiskUsage(),
		"services": collectServiceStatus(r),
	}
	writeJSON(w, http.StatusOK, status)
}

func collectDiskUsage() []diskUsage {
	paths := []string{"/"}
	var usages []diskUsage
	for _, path := range paths {
		var stat syscall.Statfs_t
		if err := syscall.Statfs(path, &stat); err != nil {
			continue
		}
		total := stat.Blocks * uint64(stat.Bsize)
		free := stat.Bavail * uint64(stat.Bsize)
		used := total - free
		var pct float64
		if total > 0 {
			pct = float64(used) / float64(total) * 100
		}
		usages = append(usages, diskUsage{
			Path:        path,
			TotalBytes:  total,
			FreeBytes:   free,
			UsedBytes:   used,
			UsedPercent: pct,
		})
	}
	return usages
}

func collectServiceStatus(r *http.Request) []serviceStatus {
	services := []string{"smbd", "nfs-server"}
	var statuses []serviceStatus
	for _, name := range services {
		stdout, _, err := system.Run(r.Context(), "systemctl", "is-active", name)
		state := strings.TrimSpace(stdout)
		if state == "" && err != nil {
			state = "unknown"
		}
		statuses = append(statuses, serviceStatus{
			Name:   name,
			Active: state == "active",
			State:  state,
		})
	}
	return statuses
}