refactor: use parser package for file monitor

parser/regex_parser.go

@@ -0,0 +1,64 @@
+package parser
+
+import (
+	"log/slog"
+	"regexp"
+	"strings"
+	"tixel_watch/helpers"
+	"tixel_watch/models"
+)
+
+type RegexLogParser struct {
+	Pattern  *regexp.Regexp
+	Fields   map[string]string
+	Toolname string
+}
+
+func (p *RegexLogParser) Parse(line string) (models.LogMessage, error) {
+	entry := models.LogMessage{Type: "log_entry"}
+	entry.Tool = p.Toolname
+	entry.Raw = line
+	hostname, err := helpers.GetHostname()
+	if err != nil {
+		slog.Warn("cannot get hostname")
+		return entry, err
+	}
+	entry.Host = hostname
+
+	fields := p.parseWithPattern(line)
+	if fields != nil {
+		entry.Fields = fields
+	} else {
+		entry.LogMessage = strings.TrimSpace(line)
+	}
+
+	return entry, nil
+}
+
+func (p *RegexLogParser) parseWithPattern(text string) map[string]any {
+	matches := p.Pattern.FindStringSubmatch(text)
+	if matches == nil {
+		return nil
+	}
+
+	fields := make(map[string]any)
+	subexpNames := p.Pattern.SubexpNames()
+
+	for i, match := range matches {
+		if i == 0 {
+			continue
+		}
+
+		if i < len(subexpNames) && subexpNames[i] != "" {
+			fieldName := subexpNames[i]
+
+			if mappedName, exists := p.Fields[fieldName]; exists {
+				fieldName = mappedName
+			}
+
+			fields[fieldName] = match
+		}
+	}
+
+	return fields
+}