added IMAP, LetsEncrypt, update layout

internal/mailstore/spam_test.go

@@ -0,0 +1,52 @@
+package mailstore
+
+import (
+	"net"
+	"testing"
+)
+
+// TestSpamScoreArithmetic exercises SpamScore's own weighting logic with synthetic
+// dkimPass/spfPass inputs — CheckDNSBL still runs (it does live DNS), so this only
+// asserts the score is monotonically at least as high when signals get worse, rather
+// than pinning an exact network-dependent number.
+func TestSpamScoreArithmetic(t *testing.T) {
+	clean := SpamScore("203.0.113.1", map[string]string{"subject": "hello"}, true, true)
+	noDKIM := SpamScore("203.0.113.1", map[string]string{"subject": "hello"}, false, true)
+	noSPF := SpamScore("203.0.113.1", map[string]string{"subject": "hello"}, true, false)
+	keyword := SpamScore("203.0.113.1", map[string]string{"subject": "WIN THE LOTTERY WINNER NOW"}, true, true)
+
+	if noDKIM <= clean {
+		t.Fatalf("missing DKIM should raise the score: clean=%d noDKIM=%d", clean, noDKIM)
+	}
+	if noSPF <= clean {
+		t.Fatalf("failing SPF should raise the score: clean=%d noSPF=%d", clean, noSPF)
+	}
+	if keyword <= clean {
+		t.Fatalf("a spam keyword in the subject should raise the score: clean=%d keyword=%d", clean, keyword)
+	}
+}
+
+func TestEvalSPF(t *testing.T) {
+	ip := net.ParseIP("203.0.113.10")
+	other := net.ParseIP("198.51.100.5")
+
+	tests := []struct {
+		name   string
+		record string
+		ip     net.IP
+		want   bool
+	}{
+		{"ip4 match passes", "v=spf1 ip4:203.0.113.0/24 -all", ip, true},
+		{"ip4 no match hard fails", "v=spf1 ip4:203.0.113.0/24 -all", other, false},
+		{"no all and no match is neutral", "v=spf1 ip4:203.0.113.0/24", other, true},
+		{"soft fail all is neutral for unmatched ip", "v=spf1 ip4:203.0.113.0/24 ~all", other, true},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := evalSPF(tt.record, tt.ip, "example.com", 0)
+			if got != tt.want {
+				t.Fatalf("evalSPF(%q) = %v, want %v", tt.record, got, tt.want)
+			}
+		})
+	}
+}