always set lane

packages/db/package.json

@@ -16,6 +16,7 @@
     "db:migrate": "drizzle-kit migrate",
     "check-types": "tsc --noEmit",
     "lint": "eslint .",
+    "db:fix-lanes": "node --env-file=../../apps/web/.env --import=tsx src/scripts/fix-lanes.ts",
     "db:start": "docker compose up -d",
     "db:watch": "docker compose up",
     "db:stop": "docker compose stop",
@@ -34,6 +35,7 @@
     "@zendegi/eslint-config": "workspace:*",
     "drizzle-kit": "^0.31.8",
     "eslint": "^9.17.0",
+    "tsx": "^4.21.0",
     "typescript": "catalog:"
   }
 }

packages/db/src/schema/timeline.ts

@@ -42,6 +42,7 @@ export const timelineItem = pgTable("timeline_item", {
   start: timestamp("start", { withTimezone: true }).notNull().defaultNow(),
   // Allow null to denote a event without duration
   end: timestamp("end", { withTimezone: true }),
+  lane: integer("lane").notNull().default(1),
   ...timestamps,
 });
 

packages/db/src/scripts/fix-lanes.ts

@@ -0,0 +1,88 @@
+/**
+ * One-time script to backfill lane values for existing timeline items.
+ *
+ * For each group: fetches items ordered by start, assigns lanes with
+ * the greedy algorithm, and updates the DB.
+ *
+ * Run from repo root:
+ *   node --env-file=apps/web/.env --import=tsx packages/db/src/scripts/fix-lanes.ts
+ */
+import { eq } from "drizzle-orm";
+import { drizzle } from "drizzle-orm/node-postgres";
+import { timelineGroup, timelineItem } from "../schema/timeline";
+
+const DATABASE_URL = process.env.DATABASE_URL;
+if (!DATABASE_URL) {
+  throw new Error("DATABASE_URL is required");
+}
+
+interface ItemForLane {
+  id: string;
+  start: Date;
+  end: Date | null;
+  lane: number;
+}
+
+function assignLane(
+  existing: ItemForLane[],
+  newStart: Date,
+  newEnd: Date | null
+): number {
+  const end = newEnd ?? new Date(newStart.getTime() + 24 * 60 * 60 * 1000);
+
+  for (let lane = 1; lane <= 100; lane++) {
+    const hasConflict = existing.some((item) => {
+      if (item.lane !== lane) return false;
+      const itemEnd =
+        item.end ?? new Date(item.start.getTime() + 24 * 60 * 60 * 1000);
+      return newStart < itemEnd && end > item.start;
+    });
+    if (!hasConflict) return lane;
+  }
+  return 1;
+}
+
+async function main() {
+  const db = drizzle(DATABASE_URL!);
+
+  const groups = await db.select({ id: timelineGroup.id }).from(timelineGroup);
+  console.log(`Found ${groups.length} groups`);
+
+  for (const group of groups) {
+    const items = await db
+      .select()
+      .from(timelineItem)
+      .where(eq(timelineItem.timelineGroupId, group.id))
+      .orderBy(timelineItem.start);
+
+    if (items.length === 0) continue;
+
+    const assigned: ItemForLane[] = [];
+    let updated = 0;
+
+    for (const item of items) {
+      const lane = assignLane(assigned, item.start, item.end);
+      assigned.push({ id: item.id, start: item.start, end: item.end, lane });
+
+      if (item.lane !== lane) {
+        await db
+          .update(timelineItem)
+          .set({ lane })
+          .where(eq(timelineItem.id, item.id));
+        updated++;
+      }
+    }
+
+    console.log(
+      `Group ${group.id}: ${items.length} items, ${updated} lanes updated`
+    );
+  }
+
+  console.log("Done");
+  process.exit(0);
+}
+
+main().catch((err) => {
+  console.error(err);
+  process.exit(1);
+});