package inspurlegacy

import (
	"regexp"
	"strings"
	"time"

	"git.mchus.pro/mchus/logpile/internal/models"
)

var blackboxLineRe = regexp.MustCompile(`^\[(\d{4}-\d{2}-\d{2} \d{2}:\d{2}:\d{2})\]\s*:\s*(.*)$`)

const blackboxTimeLayout = "2006-01-02 15:04:05"

// blackboxCritical / blackboxWarning classify the free-text message.
var (
	blackboxCritical = []string{"fault", "error", "under voltage protection", "power good detect pin changed from 1 to 0", "critical"}
	blackboxWarning  = []string{"warning", "predfail", "changed from 0 to 1"}
)

// ParseBlackbox parses blackbox.log ("[YYYY-MM-DD HH:MM:SS] : message"), the
// BMC's persistent power/thermal/RAID fault ring buffer.
func ParseBlackbox(content []byte) []models.Event {
	var events []models.Event
	seq := 0
	for _, line := range strings.Split(string(content), "\n") {
		line = strings.TrimSpace(line)
		m := blackboxLineRe.FindStringSubmatch(line)
		if m == nil {
			continue
		}
		ts, err := time.Parse(blackboxTimeLayout, m[1])
		if err != nil || bogusYear(ts) {
			continue
		}
		msg := strings.TrimSpace(m[2])
		msg = strings.TrimPrefix(msg, "[*]")
		seq++

		events = append(events, models.Event{
			ID:          "blackbox_" + ts.Format("20060102T150405") + "_" + itoa(seq),
			Timestamp:   ts,
			Source:      "BMC/blackbox",
			SensorType:  "blackbox",
			SensorName:  blackboxSubject(msg),
			Severity:    classify(msg, blackboxCritical, blackboxWarning),
			Description: msg,
			RawData:     line,
		})
	}
	return events
}

var blackboxSubjectRe = regexp.MustCompile(`^(PSU-?\d+|psu \d+|RAID|raid\s*\d+|CPU-?\d+|FAN-?\d+)`)

func blackboxSubject(msg string) string {
	if m := blackboxSubjectRe.FindString(msg); m != "" {
		return strings.TrimSpace(m)
	}
	return "blackbox"
}

func classify(msg string, critical, warning []string) models.Severity {
	low := strings.ToLower(msg)
	for _, p := range critical {
		if strings.Contains(low, p) {
			return models.SeverityCritical
		}
	}
	for _, p := range warning {
		if strings.Contains(low, p) {
			return models.SeverityWarning
		}
	}
	return models.SeverityInfo
}

func itoa(i int) string {
	if i == 0 {
		return "0"
	}
	neg := i < 0
	if neg {
		i = -i
	}
	var b [20]byte
	pos := len(b)
	for i > 0 {
		pos--
		b[pos] = byte('0' + i%10)
		i /= 10
	}
	if neg {
		pos--
		b[pos] = '-'
	}
	return string(b[pos:])
}