refactor: Abstract createBooking in handleNewBooking [CAL-2619] (c…

…alcom#11959)

## What does this PR do?

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In anticipation of refactoring `handleSeats` we need to abstract `createBooking` in order to get the return type. This PR is purposely aiming to do one thing so nothing is missed while refactoring `handleNewBooking`

Fixes # (issue)

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## Requirement/Documentation

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- If there is ab UI/UX design document, please, share it here.

## Type of change

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- [x] Chore (refactoring code, technical debt, workflow improvements)


## How should this be tested?

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packages/features/bookings/lib/getBookingDataSchema.ts

@@ -0,0 +1,80 @@
+import { z } from "zod";
+
+import {
+  bookingCreateSchemaLegacyPropsForApi,
+  bookingCreateBodySchemaForApi,
+  extendedBookingCreateBody,
+} from "@calcom/prisma/zod-utils";
+
+import getBookingResponsesSchema from "./getBookingResponsesSchema";
+import type { getEventTypesFromDB } from "./handleNewBooking";
+
+const getBookingDataSchema = (
+  rescheduleUid: string | undefined,
+  isNotAnApiCall: boolean,
+  eventType: Awaited<ReturnType<typeof getEventTypesFromDB>>
+) => {
+  const responsesSchema = getBookingResponsesSchema({
+    eventType: {
+      bookingFields: eventType.bookingFields,
+    },
+    view: rescheduleUid ? "reschedule" : "booking",
+  });
+  const bookingDataSchema = isNotAnApiCall
+    ? extendedBookingCreateBody.merge(
+        z.object({
+          responses: responsesSchema,
+        })
+      )
+    : bookingCreateBodySchemaForApi
+        .merge(
+          z.object({
+            responses: responsesSchema.optional(),
+          })
+        )
+        .superRefine((val, ctx) => {
+          if (val.responses && val.customInputs) {
+            ctx.addIssue({
+              code: "custom",
+              message:
+                "Don't use both customInputs and responses. `customInputs` is only there for legacy support.",
+            });
+            return;
+          }
+          const legacyProps = Object.keys(bookingCreateSchemaLegacyPropsForApi.shape);
+
+          if (val.responses) {
+            const unwantedProps: string[] = [];
+            legacyProps.forEach((legacyProp) => {
+              if (typeof val[legacyProp as keyof typeof val] !== "undefined") {
+                console.error(
+                  `Deprecated: Unexpected falsy value for: ${unwantedProps.join(
+                    ","
+                  )}. They can't be used with \`responses\`. This will become a 400 error in the future.`
+                );
+              }
+              if (val[legacyProp as keyof typeof val]) {
+                unwantedProps.push(legacyProp);
+              }
+            });
+            if (unwantedProps.length) {
+              ctx.addIssue({
+                code: "custom",
+                message: `Legacy Props: ${unwantedProps.join(",")}. They can't be used with \`responses\``,
+              });
+              return;
+            }
+          } else if (val.customInputs) {
+            const { success } = bookingCreateSchemaLegacyPropsForApi.safeParse(val);
+            if (!success) {
+              ctx.addIssue({
+                code: "custom",
+                message: `With \`customInputs\` you must specify legacy props ${legacyProps.join(",")}`,
+              });
+            }
+          }
+        });
+  return bookingDataSchema;
+};
+
+export default getBookingDataSchema;