1 files changed, 93 insertions, 0 deletions
diff --git a/libdino/src/qlite/upsert_builder.vala b/libdino/src/qlite/upsert_builder.vala
new file mode 100644
index 00000000..e9a73e4f
--- /dev/null
+++ b/libdino/src/qlite/upsert_builder.vala
@@ -0,0 +1,93 @@
+using Sqlite;
+
+namespace Dino.Qlite {
+
+public class UpsertBuilder : StatementBuilder {
+    // INTO [...]
+    private Table table;
+    private string table_name;
+
+    // VALUES [...]
+    private StatementBuilder.AbstractField[] keys = {};
+    private StatementBuilder.AbstractField[] fields = {};
+
+    internal UpsertBuilder(Database db, Table table) {
+        base(db);
+        this.table = table;
+        this.table_name = table.name;
+    }
+
+    public UpsertBuilder value<T>(Column<T> column, T value, bool key = false) {
+        if (key) {
+            keys += new Field<T>(column, value);
+        } else {
+            fields += new Field<T>(column, value);
+        }
+        return this;
+    }
+
+    public UpsertBuilder value_null<T>(Column<T> column, bool key = false) {
+        if (column.not_null) error("Can't set non-null column %s to null", column.name);
+        if (key) {
+            keys += new NullField<T>(column);
+        } else {
+            fields += new NullField<T>(column);
+        }
+        return this;
+    }
+
+    internal override Statement prepare() {
+        error("prepare() not available for upsert.");
+    }
+
+    internal Statement prepare_upsert() {
+        var unique_fields = new StringBuilder();
+        var unique_values = new StringBuilder();
+        var update_fields = new StringBuilder();
+        var update_values = new StringBuilder();
+        var update_fields_vals = new StringBuilder();
+
+        for (int i = 0; i < keys.length; i++) {
+            if (i != 0) {
+                unique_fields.append(", ");
+                unique_values.append(", ");
+            }
+            unique_fields.append(keys[i].column.name);
+            unique_values.append("?");
+        }
+
+        for (int i = 0; i < fields.length; i++) {
+            if (i != 0) {
+                update_fields.append(", ");
+                update_values.append(", ");
+                update_fields_vals.append(", ");
+            }
+            update_fields.append(fields[i].column.name);
+            update_values.append("?");
+            update_fields_vals.append(fields[i].column.name).append("=excluded.").append(fields[i].column.name);
+        }
+
+        string sql = @"INSERT INTO $table_name ($(unique_fields.str), $(update_fields.str)) VALUES ($(unique_values.str), $(update_values.str)) " +
+                @"ON CONFLICT ($(unique_fields.str)) DO UPDATE SET $(update_fields_vals.str)";
+
+        Statement stmt = db.prepare(sql);
+        for (int i = 0; i < keys.length; i++) {
+            keys[i].bind(stmt, i + 1);
+        }
+        for (int i = 0; i < fields.length; i++) {
+            fields[i].bind(stmt, i + keys.length + 1);
+        }
+
+        return stmt;
+    }
+
+    public int64 perform() {
+        if (prepare_upsert().step() != DONE) {
+            critical(@"SQLite error: %d - %s", db.errcode(), db.errmsg());
+        }
+        return db.last_insert_rowid();
+    }
+
+}
+
+}