package collector

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

// collectIPMISensors runs `ipmitool sensor` and returns parsed sensor readings.
// Returns nil if ipmitool is unavailable or produces no output.
func collectIPMISensors() *schema.HardwareSensors {
	out, err := exec.Command("ipmitool", "sensor").Output()
	if err != nil || len(out) == 0 {
		return nil
	}
	result := parseIPMISensorOutput(string(out))
	if result == nil {
		return nil
	}
	slog.Info("ipmi sensors: collected",
		"fans", len(result.Fans),
		"temperatures", len(result.Temperatures),
		"power", len(result.Power),
		"other", len(result.Other),
	)
	return result
}

// parseIPMISensorOutput parses `ipmitool sensor` text output.
// Each line: name | value | unit | status | lnr | lcr | lnc | unc | ucr | unr
func parseIPMISensorOutput(output string) *schema.HardwareSensors {
	result := &schema.HardwareSensors{}
	seen := map[string]struct{}{}

	for _, line := range strings.Split(output, "\n") {
		line = strings.TrimSpace(line)
		if line == "" {
			continue
		}
		parts := strings.Split(line, "|")
		if len(parts) < 4 {
			continue
		}
		name := strings.TrimSpace(parts[0])
		rawVal := strings.TrimSpace(parts[1])
		unit := strings.TrimSpace(parts[2])
		status := strings.TrimSpace(parts[3])

		if name == "" || rawVal == "na" || rawVal == "N/A" || rawVal == "" {
			continue
		}

		value, err := strconv.ParseFloat(rawVal, 64)
		if err != nil {
			continue
		}

		statusStr := normalizeIPMISensorStatus(status)

		switch {
		case strings.EqualFold(unit, "RPM"):
			if duplicateSensor(seen, "fan", name) {
				continue
			}
			rpm := int(value)
			item := schema.HardwareFanSensor{Name: name, RPM: &rpm}
			if statusStr != "" {
				item.Status = &statusStr
			}
			result.Fans = append(result.Fans, item)

		case strings.EqualFold(unit, "degrees C") || strings.EqualFold(unit, "C"):
			if duplicateSensor(seen, "temp", name) {
				continue
			}
			item := schema.HardwareTemperatureSensor{Name: name, Celsius: &value}
			if len(parts) >= 9 {
				if unc := parseIPMIThreshold(parts[7]); unc != nil {
					item.ThresholdWarningCelsius = unc
				}
				if ucr := parseIPMIThreshold(parts[8]); ucr != nil {
					item.ThresholdCriticalCelsius = ucr
				}
			}
			if statusStr != "" {
				item.Status = &statusStr
			} else {
				item.Status = deriveTemperatureStatus(item.Celsius, item.ThresholdWarningCelsius, item.ThresholdCriticalCelsius)
			}
			result.Temperatures = append(result.Temperatures, item)

		case strings.EqualFold(unit, "Volts") || strings.EqualFold(unit, "V"):
			if duplicateSensor(seen, "power", name) {
				continue
			}
			item := schema.HardwarePowerSensor{Name: name, VoltageV: &value}
			if statusStr != "" {
				item.Status = &statusStr
			}
			result.Power = append(result.Power, item)

		case strings.EqualFold(unit, "Watts") || strings.EqualFold(unit, "W"):
			if duplicateSensor(seen, "power", name) {
				continue
			}
			item := schema.HardwarePowerSensor{Name: name, PowerW: &value}
			if statusStr != "" {
				item.Status = &statusStr
			}
			result.Power = append(result.Power, item)

		case strings.EqualFold(unit, "Amps") || strings.EqualFold(unit, "A"):
			if duplicateSensor(seen, "power", name) {
				continue
			}
			item := schema.HardwarePowerSensor{Name: name, CurrentA: &value}
			if statusStr != "" {
				item.Status = &statusStr
			}
			result.Power = append(result.Power, item)

		default:
			if duplicateSensor(seen, "other", name) {
				continue
			}
			item := schema.HardwareOtherSensor{Name: name, Value: &value}
			if unit != "" {
				item.Unit = &unit
			}
			if statusStr != "" {
				item.Status = &statusStr
			}
			result.Other = append(result.Other, item)
		}
	}

	if len(result.Fans) == 0 && len(result.Temperatures) == 0 && len(result.Power) == 0 && len(result.Other) == 0 {
		return nil
	}
	return result
}

func parseIPMIThreshold(raw string) *float64 {
	s := strings.TrimSpace(raw)
	if s == "" || s == "na" || s == "N/A" {
		return nil
	}
	v, err := strconv.ParseFloat(s, 64)
	if err != nil {
		return nil
	}
	return &v
}

func normalizeIPMISensorStatus(s string) string {
	switch strings.ToLower(s) {
	case "ok":
		return statusOK
	case "cr", "ucr", "lcr":
		return statusCritical
	case "nc", "unc", "lnc", "nr", "unr", "lnr":
		return statusWarning
	case "ns", "na":
		return ""
	default:
		return ""
	}
}

// mergeIPMISensors appends IPMI sensor entries into existing, skipping names already present.
func mergeIPMISensors(existing, ipmi *schema.HardwareSensors) *schema.HardwareSensors {
	if ipmi == nil {
		return existing
	}
	if existing == nil {
		return ipmi
	}

	existingNames := map[string]struct{}{}
	for _, s := range existing.Fans {
		existingNames["fan\x00"+s.Name] = struct{}{}
	}
	for _, s := range existing.Temperatures {
		existingNames["temp\x00"+s.Name] = struct{}{}
	}
	for _, s := range existing.Power {
		existingNames["power\x00"+s.Name] = struct{}{}
	}
	for _, s := range existing.Other {
		existingNames["other\x00"+s.Name] = struct{}{}
	}

	for _, s := range ipmi.Fans {
		if _, ok := existingNames["fan\x00"+s.Name]; !ok {
			existing.Fans = append(existing.Fans, s)
		}
	}
	for _, s := range ipmi.Temperatures {
		if _, ok := existingNames["temp\x00"+s.Name]; !ok {
			existing.Temperatures = append(existing.Temperatures, s)
		}
	}
	for _, s := range ipmi.Power {
		if _, ok := existingNames["power\x00"+s.Name]; !ok {
			existing.Power = append(existing.Power, s)
		}
	}
	for _, s := range ipmi.Other {
		if _, ok := existingNames["other\x00"+s.Name]; !ok {
			existing.Other = append(existing.Other, s)
		}
	}
	return existing
}