better indexing and classifier

pkg/index/classify.go

@@ -0,0 +1,30 @@
+package index
+
+import (
+	"regexp"
+)
+
+var classes = []class{
+	{regexp.MustCompile(`(?i)[^e]rechnung|quittung|beleg|invoice|bill|check`), []string{"invoice", "rechnung"}},
+	{regexp.MustCompile(`(?i)steuer|lohn|tax|salary`), []string{"tax", "steuer"}},
+	{regexp.MustCompile(`(?i)vertrag|kündigung|vereinbarung|contract|termination|agreement`), []string{"contract", "vertrag"}},
+	{regexp.MustCompile(`(?i)versicherung|versichert|insurance|insured`), []string{"insurance", "versicherung"}},
+}
+
+type class struct {
+	r *regexp.Regexp
+	k []string
+}
+
+func classify(text string) (keyword []string) {
+	keyword = []string{"", ""}
+	n := 0
+	for _, v := range classes {
+		num := len(v.r.FindAllString(text, -1))
+		if num > n && num >= 2 {
+			keyword = v.k
+			n = num
+		}
+	}
+	return
+}