import { z } from 'zod';

/**
 * Page schemas and views shared between api and web (issue #23). A page
 * carries a Yjs document from day one (ADR 0003); in M2 its state is
 * saved wholesale over REST as a base64 string.
 */

export const pageTitleSchema = z
  .string()
  .trim()
  .min(1, 'validation.required')
  .max(200, 'validation.tooLong');

export const pageSlugSchema = z
  .string()
  .trim()
  .min(1, 'validation.required')
  .max(60, 'validation.tooLong');

export const createPageInputSchema = z.object({
  title: pageTitleSchema,
});
export type CreatePageInput = z.infer<typeof createPageInputSchema>;

export const updatePageInputSchema = z
  .object({
    title: pageTitleSchema,
    slug: pageSlugSchema,
  })
  .partial();
export type UpdatePageInput = z.infer<typeof updatePageInputSchema>;

/**
 * Move a page in the manual sidebar order (issue #45): place it between the
 * `afterId` page (its new predecessor) and the `beforeId` page (its new
 * successor); either is `null` at an end of the list. The server recomputes
 * only the moved page's `sort_key`.
 */
export const repositionPageInputSchema = z.object({
  afterId: z.string().min(1).nullable(),
  beforeId: z.string().min(1).nullable(),
});
export type RepositionPageInput = z.infer<typeof repositionPageInputSchema>;

export const savePageStateInputSchema = z.object({
  /** Base64-encoded Yjs state (`Y.encodeStateAsUpdate`). */
  state: z.string().min(1, 'validation.required'),
});
export type SavePageStateInput = z.infer<typeof savePageStateInputSchema>;

/** Max Yjs document size (operations.md §Limits) — a fixed operational
 * ceiling, not a per-pond/user quota. */
export const MAX_PAGE_DOCUMENT_BYTES = 5 * 1024 * 1024;

export interface PageView {
  id: string;
  pondId: string;
  title: string;
  slug: string;
  sortKey: string;
  createdAt: string;
  updatedAt: string;
  deletedAt: string | null;
}

/** What `GET /pages/:id` returns: page meta plus its base64 Yjs state. */
export interface PageStateView extends PageView {
  state: string;
}

/**
 * A page in the sidebar list (`GET /ponds/:id/pages`) with the ids of the
 * labels assigned to it (issue #44). The sidebar maps these to colours/names
 * via the pond's label tree for chips and filters by them (descendant-inclusive
 * via the shared tree helpers) — so no per-label detail is repeated here.
 */
export interface PageListItemView extends PageView {
  labelIds: string[];
}

/** Why a version snapshot exists (ADR 0013): automatic (session end / active
 * interval), a named manual snapshot, or the automatic pre-restore snapshot. */
export type PageVersionTrigger = 'auto' | 'manual' | 'pre_restore';

export const createVersionInputSchema = z.object({
  label: z.string().trim().min(1, 'validation.required').max(100, 'validation.tooLong'),
});
export type CreateVersionInput = z.infer<typeof createVersionInputSchema>;

/** A version in the history list (issue #41; no snapshot bytes). */
export interface PageVersionView {
  id: string;
  pageId: string;
  trigger: PageVersionTrigger;
  label: string | null;
  /** Editor for manual/pre-restore versions; null for automatic snapshots. */
  createdBy: string | null;
  /** Users who edited since the previous version. */
  contributorIds: string[];
  /** Display names for contributorIds; deleted accounts are omitted. */
  contributors: { id: string; name: string }[];
  createdAt: string;
}

/** A single version with its rendered content, for viewing/diffing (issue #42). */
export interface PageVersionContentView extends PageVersionView {
  /** Read-only HTML render of the snapshot. */
  html: string;
  /** Markdown of the snapshot, for the diff against the current page. */
  markdown: string;
}