Implement DB auto init

db.go

@@ -3,6 +3,7 @@ package main
 import (
 	"database/sql"
 	"fmt"
+	"log"
 	"time"
 
 	_ "github.com/mattn/go-sqlite3"
@@ -44,6 +45,58 @@ func (db *DB) Open() error {
 	return nil
 }
 
+func (db *DB) Init(ddl string) error {
+	if !db.Ready {
+		return fmt.Errorf("database not ready")
+	}
+
+	var rows map[string]struct{} = make(map[string]struct{})
+	// TODO: Maybe make this better one day...
+	var expected = map[string]struct{}{
+		"food":     {},
+		"weight":   {},
+		"settings": {},
+	}
+
+	res, err := db.readConn.Query("SELECT name FROM sqlite_master WHERE type='table';")
+	if err != nil {
+		Error.Printf("%++v", err)
+		return err
+	}
+	defer res.Close()
+	for res.Next() {
+		var name string
+		err := res.Scan(&name)
+		if err != nil {
+			Error.Printf("%++v", err)
+			return err
+		}
+		rows[name] = struct{}{}
+	}
+
+	var needsInit bool
+	for table := range expected {
+		if _, ok := rows[table]; !ok {
+			log.Printf("Table %s not found, initializing", table)
+			needsInit = true
+			break;
+		}
+	}
+
+	if !needsInit {
+		log.Printf("Database already initialized")
+		return nil
+	}
+
+	_, err = db.writeConn.Exec(ddl)
+	if err != nil {
+		Error.Printf("%++v", err)
+		return err
+	}
+
+	return nil
+}
+
 func (db *DB) Close() error {
 	err := db.writeConn.Close()
 	if err != nil {