Break up common functions and small refactor.

common/snapshot.go

@@ -0,0 +1,56 @@
+package common
+
+import (
+	"database/sql/driver"
+	"encoding/json"
+	"fmt"
+	"time"
+
+	"github.com/guregu/null/v5"
+)
+
+type LinkList []URL
+
+func (l *LinkList) Value() (driver.Value, error) {
+	return json.Marshal(l)
+}
+
+func (l *LinkList) Scan(value interface{}) error {
+	if value == nil {
+		*l = nil
+		return nil
+	}
+	b, ok := value.([]byte) // Type assertion! Converts to []byte
+	if !ok {
+		return fmt.Errorf("failed to scan LinkList: expected []byte, got %T", value)
+	}
+	return json.Unmarshal(b, l)
+}
+
+type Snapshot struct {
+	ID           int                  `db:"id" json:"id,omitempty"`
+	URL          URL                  `db:"url" json:"url,omitempty"`
+	Host         string               `db:"host" json:"host,omitempty"`
+	Timestamp    null.Time            `db:"timestamp" json:"timestamp,omitempty"`
+	MimeType     null.String          `db:"mimetype" json:"mimetype,omitempty"`
+	Data         null.Value[[]byte]   `db:"data" json:"data,omitempty"`       // For non text/gemini files.
+	GemText      null.String          `db:"gemtext" json:"gemtext,omitempty"` // For text/gemini files.
+	Header       null.String          `db:"header" json:"header,omitempty"`   // Response header.
+	Links        null.Value[LinkList] `db:"links" json:"links,omitempty"`
+	Lang         null.String          `db:"lang" json:"lang,omitempty"`
+	ResponseCode null.Int             `db:"response_code" json:"code,omitempty"` // Gemini response status code.
+	Error        null.String          `db:"error" json:"error,omitempty"`        // On network errors only
+}
+
+func SnapshotFromURL(u string) *Snapshot {
+	url, err := ParseURL(u, "")
+	if err != nil {
+		return nil
+	}
+	newSnapshot := Snapshot{
+		URL:       *url,
+		Host:      url.Hostname,
+		Timestamp: null.TimeFrom(time.Now()),
+	}
+	return &newSnapshot
+}