added availability

prisma/migrations/20260430170142_booking_spike/migration.sql

@@ -0,0 +1,62 @@
+-- CreateEnum
+CREATE TYPE "BookingStatus" AS ENUM ('HOLD', 'CONFIRMED', 'COMPLETED', 'NO_SHOW', 'CANCELLED');
+
+-- CreateTable
+CREATE TABLE "Booking" (
+    "id" TEXT NOT NULL,
+    "customerId" TEXT NOT NULL,
+    "therapistId" TEXT NOT NULL,
+    "roomId" TEXT NOT NULL,
+    "serviceId" TEXT NOT NULL,
+    "startsAt" TIMESTAMPTZ(3) NOT NULL,
+    "endsAt" TIMESTAMPTZ(3) NOT NULL,
+    "roomReleasedAt" TIMESTAMPTZ(3) NOT NULL,
+    "status" "BookingStatus" NOT NULL DEFAULT 'HOLD',
+    "holdExpiresAt" TIMESTAMPTZ(3),
+    "priceCents" INTEGER NOT NULL DEFAULT 0,
+    "depositCents" INTEGER NOT NULL DEFAULT 0,
+    "createdAt" TIMESTAMPTZ(3) NOT NULL DEFAULT CURRENT_TIMESTAMP,
+    "updatedAt" TIMESTAMPTZ(3) NOT NULL,
+
+    CONSTRAINT "Booking_pkey" PRIMARY KEY ("id")
+);
+
+-- CreateIndex
+CREATE INDEX "Booking_startsAt_idx" ON "Booking"("startsAt");
+
+-- CreateIndex
+CREATE INDEX "Booking_therapistId_startsAt_idx" ON "Booking"("therapistId", "startsAt");
+
+-- CreateIndex
+CREATE INDEX "Booking_roomId_startsAt_idx" ON "Booking"("roomId", "startsAt");
+
+-- CreateIndex
+CREATE INDEX "Booking_status_holdExpiresAt_idx" ON "Booking"("status", "holdExpiresAt");
+
+-- Required extension for combining a UUID/text equality with a range type in EXCLUDE constraints.
+-- Created out-of-band by db/init/01-extensions-and-test-db.sql; safe to re-run.
+CREATE EXTENSION IF NOT EXISTS btree_gist;
+
+-- Double-booking safety net. App-level availability search prevents most conflicts;
+-- these constraints are the last line of defense for race conditions and bugs.
+-- Only HOLD and CONFIRMED rows are subject to the constraint — cancelled/completed
+-- rows are historical and may overlap freely (e.g., a no-show then a same-slot booking).
+
+-- A therapist can only be in one active booking at a time.
+ALTER TABLE "Booking"
+  ADD CONSTRAINT "Booking_no_therapist_overlap"
+  EXCLUDE USING gist (
+    "therapistId" WITH =,
+    tstzrange("startsAt", "endsAt", '[)') WITH &&
+  )
+  WHERE (status IN ('HOLD', 'CONFIRMED'));
+
+-- A room can only host one active booking at a time, including its post-service buffer.
+ALTER TABLE "Booking"
+  ADD CONSTRAINT "Booking_no_room_overlap"
+  EXCLUDE USING gist (
+    "roomId" WITH =,
+    tstzrange("startsAt", "roomReleasedAt", '[)') WITH &&
+  )
+  WHERE (status IN ('HOLD', 'CONFIRMED'));
+