chunithm: Initial implementation code drop

No cleaner development history than this exists. It's difficult to
methodically design something when you don't yet know what it is
you're designing.

src/chunithm/sql/userActivity.ts

@@ -0,0 +1,50 @@
+import sql from "sql-bricks-postgres";
+
+import { UserActivityItem } from "../model/userActivity";
+import { UserDataItem } from "../model/userData";
+import { UserActivityRepository } from "../repo/userActivity";
+import { Id } from "../../model";
+import { Transaction } from "../../sql";
+import { T, createSqlMapper } from "../../sql/util";
+
+const { readRow, writeRow, colNames } = createSqlMapper({
+  kind: T.number,
+  activityId: T.number, // This is just called "id" on the wire
+  sortNumber: T.number,
+  param1: T.number,
+  param2: T.number,
+  param3: T.number,
+  param4: T.number,
+});
+
+export class SqlUserActivityRepository implements UserActivityRepository {
+  constructor(private readonly _txn: Transaction) {}
+
+  async load(
+    profileId: Id<UserDataItem>,
+    kind: number
+  ): Promise<UserActivityItem[]> {
+    const stmt = sql
+      .select("*")
+      .from("cm_user_activity")
+      .where("profile_id", profileId)
+      .where("kind", kind);
+
+    const rows = await this._txn.fetchRows(stmt);
+
+    return rows.map(readRow);
+  }
+
+  save(profileId: Id<UserDataItem>, obj: UserActivityItem): Promise<void> {
+    const stmt = sql
+      .insert("cm_user_activity", {
+        id: this._txn.generateId(),
+        profile_id: profileId,
+        ...writeRow(obj),
+      })
+      .onConflict("profile_id", "kind", "activity_id")
+      .doUpdate(colNames);
+
+    return this._txn.modify(stmt);
+  }
+}