import { z } from "zod";

export const EntityIdSchema = z.string().regex(/^[a-z]+_[a-zA-Z0-9_-]+$/);
export const AttachmentIdSchema = z.string().regex(/^att_[a-zA-Z0-9_-]+$/);

export const MessageInputSchema = z.object({
  text: z.string().max(100_000).default(""),
  attachmentIds: z.array(AttachmentIdSchema).max(4).default([]),
}).strict().superRefine((value, context) => {
  if (value.text.trim().length === 0 && value.attachmentIds.length === 0) {
    context.addIssue({
      code: "custom",
      path: ["text"],
      message: "A message requires text or at least one attachment",
    });
  }

  if (new Set(value.attachmentIds).size !== value.attachmentIds.length) {
    context.addIssue({
      code: "custom",
      path: ["attachmentIds"],
      message: "Attachment IDs must be unique",
    });
  }
});

export const ImageAttachmentSchema = z.object({
  attachmentId: AttachmentIdSchema,
  sessionId: z.string().regex(/^ses_[a-zA-Z0-9_-]+$/),
  name: z.string().trim().min(1).max(255),
  mediaType: z.enum(["image/jpeg", "image/png", "image/webp"]),
  byteSize: z.int().positive(),
  width: z.int().positive(),
  height: z.int().positive(),
  status: z.literal("ready"),
}).strict();

export type MessageInput = z.infer<typeof MessageInputSchema>;
export type ImageAttachment = z.infer<typeof ImageAttachmentSchema>;