package collector

import (
	"bee/audit/internal/schema"
	"encoding/json"
	"log/slog"
	"os/exec"
	"strings"
)

func collectStorage() []schema.HardwareStorage {
	devs := lsblkDevices()
	result := make([]schema.HardwareStorage, 0, len(devs))
	for _, dev := range devs {
		var s schema.HardwareStorage
		if strings.HasPrefix(dev.Name, "nvme") {
			s = enrichWithNVMe(dev)
		} else {
			s = enrichWithSmartctl(dev)
		}
		result = append(result, s)
	}
	slog.Info("storage: collected", "count", len(result))
	return result
}

// lsblkDevice is a minimal lsblk JSON record.
type lsblkDevice struct {
	Name     string `json:"name"`
	Type     string `json:"type"`
	Size     string `json:"size"`
	Serial   string `json:"serial"`
	Model    string `json:"model"`
	Tran     string `json:"tran"`
	Hctl     string `json:"hctl"`
}

type lsblkRoot struct {
	Blockdevices []lsblkDevice `json:"blockdevices"`
}

func lsblkDevices() []lsblkDevice {
	out, err := exec.Command("lsblk", "-J", "-d",
		"-o", "NAME,TYPE,SIZE,SERIAL,MODEL,TRAN,HCTL").Output()
	if err != nil {
		slog.Warn("storage: lsblk failed", "err", err)
		return nil
	}
	var root lsblkRoot
	if err := json.Unmarshal(out, &root); err != nil {
		slog.Warn("storage: lsblk parse failed", "err", err)
		return nil
	}
	var disks []lsblkDevice
	for _, d := range root.Blockdevices {
		if d.Type == "disk" {
			disks = append(disks, d)
		}
	}
	return disks
}

// smartctlInfo is the subset of smartctl -j -a output we care about.
type smartctlInfo struct {
	ModelFamily  string `json:"model_family"`
	ModelName    string `json:"model_name"`
	SerialNumber string `json:"serial_number"`
	FirmwareVer  string `json:"firmware_version"`
	RotationRate int    `json:"rotation_rate"`
	UserCapacity struct {
		Bytes int64 `json:"bytes"`
	} `json:"user_capacity"`
	AtaSmartAttributes struct {
		Table []struct {
			ID    int    `json:"id"`
			Name  string `json:"name"`
			Raw   struct{ Value int64 `json:"value"` } `json:"raw"`
		} `json:"table"`
	} `json:"ata_smart_attributes"`
	PowerOnTime struct {
		Hours int `json:"hours"`
	} `json:"power_on_time"`
	PowerCycleCount int `json:"power_cycle_count"`
}

func enrichWithSmartctl(dev lsblkDevice) schema.HardwareStorage {
	present := true
	s := schema.HardwareStorage{Present: &present}

	tran := strings.ToLower(dev.Tran)
	devPath := "/dev/" + dev.Name

	// determine device type (refined by smartctl rotation_rate below)
	var devType string
	switch {
	case strings.HasPrefix(dev.Name, "nvme"):
		devType = "NVMe"
	case tran == "usb":
		devType = "USB"
	case tran == "sata" || tran == "sas":
		devType = "HDD" // refined to SSD below if rotation_rate==0
	default:
		devType = "Unknown"
	}

	iface := strings.ToUpper(tran)
	if iface != "" {
		s.Interface = &iface
	}

	// slot from HCTL (host:channel:target:lun)
	if dev.Hctl != "" {
		s.Slot = &dev.Hctl
	}

	// run smartctl
	out, err := exec.Command("smartctl", "-j", "-a", devPath).Output()
	if err != nil {
		// still fill what lsblk gave us
		if v := strings.TrimSpace(dev.Model); v != "" {
			s.Model = &v
		}
		if v := strings.TrimSpace(dev.Serial); v != "" {
			s.SerialNumber = &v
		}
		s.Type = &devType
		return s
	}

	var info smartctlInfo
	if err := json.Unmarshal(out, &info); err == nil {
		if v := cleanDMIValue(info.ModelName); v != "" {
			s.Model = &v
		}
		if v := cleanDMIValue(info.SerialNumber); v != "" {
			s.SerialNumber = &v
		}
		if v := cleanDMIValue(info.FirmwareVer); v != "" {
			s.Firmware = &v
		}
		if info.UserCapacity.Bytes > 0 {
			gb := int(info.UserCapacity.Bytes / 1_000_000_000)
			s.SizeGB = &gb
		}

		// refine type from rotation_rate
		if info.RotationRate == 0 && devType != "NVMe" && devType != "USB" {
			devType = "SSD"
		} else if info.RotationRate > 0 {
			devType = "HDD"
		}

		// telemetry
		tel := map[string]any{}
		if info.PowerOnTime.Hours > 0 {
			tel["power_on_hours"] = info.PowerOnTime.Hours
		}
		if info.PowerCycleCount > 0 {
			tel["power_cycles"] = info.PowerCycleCount
		}
		for _, attr := range info.AtaSmartAttributes.Table {
			switch attr.ID {
			case 5:
				tel["reallocated_sectors"] = attr.Raw.Value
			case 177:
				tel["wear_leveling_pct"] = attr.Raw.Value
			case 231:
				tel["life_remaining_pct"] = attr.Raw.Value
			case 241:
				tel["total_lba_written"] = attr.Raw.Value
			}
		}
		if len(tel) > 0 {
			s.Telemetry = tel
		}
	}

	s.Type = &devType
	status := "OK"
	s.Status = &status
	return s
}

// nvmeSmartLog is the subset of `nvme smart-log -o json` output we care about.
type nvmeSmartLog struct {
	PercentageUsed   int   `json:"percentage_used"`
	PowerOnHours     int64 `json:"power_on_hours"`
	PowerCycles      int64 `json:"power_cycles"`
	UnsafeShutdowns  int64 `json:"unsafe_shutdowns"`
	DataUnitsWritten int64 `json:"data_units_written"`
	ControllerBusy   int64 `json:"controller_busy_time"`
}

// nvmeIDCtrl is the subset of `nvme id-ctrl -o json` output.
type nvmeIDCtrl struct {
	ModelNumber    string `json:"mn"`
	SerialNumber   string `json:"sn"`
	FirmwareRev    string `json:"fr"`
	TotalCapacity  int64  `json:"tnvmcap"`
}

func enrichWithNVMe(dev lsblkDevice) schema.HardwareStorage {
	present := true
	devType := "NVMe"
	iface := "NVMe"
	status := "OK"
	s := schema.HardwareStorage{
		Present:   &present,
		Type:      &devType,
		Interface: &iface,
		Status:    &status,
	}

	devPath := "/dev/" + dev.Name

	// id-ctrl: model, serial, firmware, capacity
	if out, err := exec.Command("nvme", "id-ctrl", devPath, "-o", "json").Output(); err == nil {
		var ctrl nvmeIDCtrl
		if json.Unmarshal(out, &ctrl) == nil {
			if v := cleanDMIValue(strings.TrimSpace(ctrl.ModelNumber)); v != "" {
				s.Model = &v
			}
			if v := cleanDMIValue(strings.TrimSpace(ctrl.SerialNumber)); v != "" {
				s.SerialNumber = &v
			}
			if v := cleanDMIValue(strings.TrimSpace(ctrl.FirmwareRev)); v != "" {
				s.Firmware = &v
			}
			if ctrl.TotalCapacity > 0 {
				gb := int(ctrl.TotalCapacity / 1_000_000_000)
				s.SizeGB = &gb
			}
		}
	}

	// smart-log: wear telemetry
	if out, err := exec.Command("nvme", "smart-log", devPath, "-o", "json").Output(); err == nil {
		var log nvmeSmartLog
		if json.Unmarshal(out, &log) == nil {
			tel := map[string]any{}
			if log.PowerOnHours > 0 {
				tel["power_on_hours"] = log.PowerOnHours
			}
			if log.PowerCycles > 0 {
				tel["power_cycles"] = log.PowerCycles
			}
			if log.UnsafeShutdowns > 0 {
				tel["unsafe_shutdowns"] = log.UnsafeShutdowns
			}
			if log.PercentageUsed > 0 {
				tel["percentage_used"] = log.PercentageUsed
			}
			if log.DataUnitsWritten > 0 {
				tel["data_units_written"] = log.DataUnitsWritten
			}
			if log.ControllerBusy > 0 {
				tel["controller_busy_time"] = log.ControllerBusy
			}
			if len(tel) > 0 {
				s.Telemetry = tel
			}
		}
	}

	return s
}