package webui

import (
	"bytes"
	"context"
	"log/slog"
	"os/exec"
	"time"

	"bee/audit/internal/app"
	"bee/audit/internal/collector"
)

const healthPollInterval = 60 * time.Second
const psuIPMITimeout = 15 * time.Second

// healthPoller runs periodic health checks for hardware components that do not
// emit kernel log events (e.g. PSU). Results are written to ComponentStatusDB.
type healthPoller struct {
	statusDB *app.ComponentStatusDB
}

func newHealthPoller(statusDB *app.ComponentStatusDB) *healthPoller {
	return &healthPoller{statusDB: statusDB}
}

func (p *healthPoller) start() {
	goRecoverLoop("health poller", 5*time.Second, p.run)
}

func (p *healthPoller) run() {
	ticker := time.NewTicker(healthPollInterval)
	defer ticker.Stop()
	for range ticker.C {
		p.pollPSU()
	}
}

func (p *healthPoller) pollPSU() {
	if p.statusDB == nil {
		return
	}
	ctx, cancel := context.WithTimeout(context.Background(), psuIPMITimeout)
	defer cancel()

	cmd := exec.CommandContext(ctx, "ipmitool", "sdr")
	var out bytes.Buffer
	cmd.Stdout = &out
	if err := cmd.Run(); err != nil {
		// IPMI not available or not a server — skip silently.
		slog.Debug("health poller: ipmitool sdr unavailable", "err", err)
		return
	}

	slots := collector.PSUSlotsFromSDR(out.String())
	if len(slots) == 0 {
		return
	}

	const source = "watchdog:psu"
	for slot, psu := range slots {
		key := "psu:" + slot
		status := psu.Status
		if status == "" {
			status = "Unknown"
		}
		detail := ""
		switch status {
		case "Critical":
			detail = "PSU sensor reported non-OK state"
		case "Warning":
			detail = "PSU sensor in warning state"
		}
		p.statusDB.Record(key, source, status, detail)
	}
}