import * as z from "zod";

/** Cap for a custom ComfyUI workflow (API-format JSON). */
export const MEDIA_WORKFLOW_MAX_LENGTH = 512 * 1024;

/** Empty form fields mean "not set". */
function optionalText(max: number) {
  return z
    .string()
    .trim()
    .max(max)
    .optional()
    .transform((value) => value || undefined);
}

function isJsonObject(value: string | undefined): boolean {
  if (value === undefined) return true;
  try {
    const parsed: unknown = JSON.parse(value);
    return typeof parsed === "object" && parsed !== null && !Array.isArray(parsed);
  } catch {
    return false;
  }
}

const workflow = optionalText(MEDIA_WORKFLOW_MAX_LENGTH).refine(isJsonObject, {
  message: "Workflow must be a JSON object",
});

/** Image and video generation on the deployment owner's ComfyUI server. */
export const ComfyUiSettingsSchema = z.object({
  baseUrl: z.string().trim().min(1).max(2048),
  apiKey: optionalText(4096),
  /** Checkpoint name; the first installed checkpoint when unset. */
  imageModel: optionalText(512),
  /** Custom API-format workflows that replace the built-in defaults. */
  imageWorkflow: workflow,
  videoWorkflow: workflow,
});
export type ComfyUiSettings = z.infer<typeof ComfyUiSettingsSchema>;

/** Speech to text on an OpenAI-compatible server (`POST /v1/audio/transcriptions`). */
export const TranscriptionSettingsSchema = z.object({
  baseUrl: z.string().trim().min(1).max(2048),
  model: optionalText(512),
  apiKey: optionalText(4096),
});
export type TranscriptionSettings = z.infer<typeof TranscriptionSettingsSchema>;

/** Deployment-wide media backends; null means the backend is not configured. */
export const MediaSettingsSchema = z.object({
  comfyui: ComfyUiSettingsSchema.nullable(),
  transcription: TranscriptionSettingsSchema.nullable(),
});
export type MediaSettings = z.infer<typeof MediaSettingsSchema>;

/** What the settings screen reads: saved keys are never returned, only whether one exists. */
export const MediaSettingsViewSchema = z.object({
  comfyui: ComfyUiSettingsSchema.omit({ apiKey: true })
    .extend({ hasApiKey: z.boolean() })
    .nullable(),
  transcription: TranscriptionSettingsSchema.omit({ apiKey: true })
    .extend({ hasApiKey: z.boolean() })
    .nullable(),
});
export type MediaSettingsView = z.infer<typeof MediaSettingsViewSchema>;

const keyUpdate = z.string().trim().max(4096).optional();

/**
 * Saving replaces both backends. An omitted `apiKey` keeps the saved key while the server's
 * origin stays the same; an empty one removes it.
 */
export const MediaSettingsUpdateSchema = z.object({
  comfyui: ComfyUiSettingsSchema.extend({ apiKey: keyUpdate }).nullable(),
  transcription: TranscriptionSettingsSchema.extend({ apiKey: keyUpdate }).nullable(),
});
export type MediaSettingsUpdate = z.input<typeof MediaSettingsUpdateSchema>;