/**
 * V9 case open request/response contracts.
 *
 * The browser submits only an intent + idempotency key (+ exact sessionId for
 * the session intent). The server owns profile normalization, baseline
 * snapshot/fingerprint generation, candidate range derivation and every
 * disposition decision.
 */
import { z } from "zod";
import {
  isRectificationCaseStatus,
  type RectificationCaseStatus,
} from "./case-status";

export const OPEN_RECTIFICATION_INTENTS = [
  "homepage",
  "session",
  "new",
] as const;

export type OpenRectificationIntent =
  (typeof OPEN_RECTIFICATION_INTENTS)[number];

export const openRectificationCaseRequestSchema = z.discriminatedUnion(
  "intent",
  [
    z
      .object({
        intent: z.literal("homepage"),
        requestId: z.string().uuid(),
      })
      .strict(),
    z
      .object({
        intent: z.literal("session"),
        requestId: z.string().uuid(),
        sessionId: z.string().uuid(),
      })
      .strict(),
    z
      .object({
        intent: z.literal("new"),
        requestId: z.string().uuid(),
        supersedeActive: z.literal(false).optional(),
      })
      .strict(),
  ],
);

export type OpenRectificationCaseRequest = z.infer<
  typeof openRectificationCaseRequestSchema
>;

export const openRectificationDispositions = [
  "created",
  "resumed",
  "readonly",
] as const;

export type OpenRectificationDisposition =
  (typeof openRectificationDispositions)[number];

export type OpenRectificationCaseResponse = Readonly<{
  disposition: OpenRectificationDisposition;
  caseId: string;
  sessionId: string;
  status: RectificationCaseStatus;
  shouldStartOpening: boolean;
  skillVersion: string;
}>;

/** Entry-summary contract used by the homepage card. */
export type RectificationEntrySummary = Readonly<{
  hasResumableCase: boolean;
  hasTerminalCaseWithTime: boolean;
  latestResumable: Readonly<{
    caseId: string;
    status: RectificationCaseStatus;
    lastActivityAt: string;
  }> | null;
  latestTerminal: Readonly<{
    caseId: string;
    status: RectificationCaseStatus;
    hasUsableTime: boolean;
  }> | null;
}>;

export function parseOpenRectificationCaseRequest(
  value: unknown,
): OpenRectificationCaseRequest | null {
  const parsed = openRectificationCaseRequestSchema.safeParse(value);
  return parsed.success ? parsed.data : null;
}

export function isOpenRectificationDisposition(
  value: unknown,
): value is OpenRectificationDisposition {
  return (
    typeof value === "string" &&
    (openRectificationDispositions as readonly string[]).includes(value)
  );
}

/**
 * shouldStartOpening is server-owned: true only for a freshly created case
 * that has never started (no turns). Resumed cases and readonly history must
 * never auto-generate an opening.
 */
export function shouldStartOpening(
  disposition: OpenRectificationDisposition,
  turnCount: number,
): boolean {
  if (disposition !== "created") return false;
  return turnCount === 0;
}

export function openResponse(
  value: unknown,
): OpenRectificationCaseResponse | null {
  if (!value || typeof value !== "object") return null;
  const row = value as Record<string, unknown>;
  const caseId = typeof row.case_id === "string" ? row.case_id : "";
  const sessionId = typeof row.session_id === "string" ? row.session_id : "";
  const skillVersion =
    typeof row.skill_version === "string" ? row.skill_version : "";
  if (
    !caseId ||
    !sessionId ||
    !skillVersion ||
    !isOpenRectificationDisposition(row.disposition) ||
    !isRectificationCaseStatus(row.status)
  ) {
    return null;
  }
  return {
    disposition: row.disposition,
    caseId,
    sessionId,
    status: row.status,
    shouldStartOpening: row.should_start_opening === true,
    skillVersion,
  };
}

/** Profile fields the server requires before a case may be opened. */
export const PROFILE_COMPLETENESS_REQUIREMENTS = [
  "birth_date",
  "latitude",
  "longitude",
  "timezone_offset",
  "birth_time_source",
] as const;