-- 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'));