import { z } from "zod";

/**
 * Lotse block of the report snapshot (client-safe, lane L9). Stored as optional `content.lotse` of
 * `ReportContent` (src/lib/reports/content.ts), so it is frozen together with the report on approval.
 *
 * Suggestions are kept SEPARATE from `content.texts`: nothing the model wrote reaches the report text
 * until a person accepts it (Spec §15.3/§15.4, Brandbook §12.4). `reviewedAt` is set on submit when
 * the submitter confirmed "Ich habe den Vorschlag geprüft" (checked server-side in submitReport).
 */

/** Report text fields the Lotse drafts (ReportDraftOutput); `problems` stays technician-only. */
export const LOTSE_TEXT_FIELDS = ["workPerformed", "deviations", "additionalWork", "openItems", "nextSteps", "hints"] as const;
export type LotseTextField = (typeof LOTSE_TEXT_FIELDS)[number];

export const LOTSE_SUGGESTION_STATES = ["pending", "accepted", "discarded"] as const;
export type LotseSuggestionState = (typeof LOTSE_SUGGESTION_STATES)[number];

export const LOTSE_TEXT_MAX = 10_000;
export const LOTSE_MISSING_MAX = 20;

const isoDateTime = z.string().datetime({ offset: true });

export const lotseSuggestionSchema = z.object({
  field: z.enum(LOTSE_TEXT_FIELDS),
  text: z.string().max(LOTSE_TEXT_MAX),
  state: z.enum(LOTSE_SUGGESTION_STATES),
  decidedAt: isoDateTime.nullable(),
});
export type LotseSuggestion = z.infer<typeof lotseSuggestionSchema>;

export const lotseBlockSchema = z.object({
  generationId: z.string(),
  model: z.string(),
  draftedAt: isoDateTime,
  draftedById: z.string().nullable(),
  suggestions: z.array(lotseSuggestionSchema),
  /** plain-language hints of what the model could not find in the data */
  missingInformation: z.array(z.string().max(500)).max(LOTSE_MISSING_MAX),
  reviewedAt: isoDateTime.nullable(),
  reviewedById: z.string().nullable(),
});
export type LotseBlock = z.infer<typeof lotseBlockSchema>;

export const LOTSE_ADDRESS_FORMS = ["sie", "du"] as const;
export type LotseAddressForm = (typeof LOTSE_ADDRESS_FORMS)[number];

export function pendingSuggestions(block: LotseBlock | null | undefined): LotseSuggestion[] {
  return block ? block.suggestions.filter((s) => s.state === "pending") : [];
}