import {z} from 'zod'

export type TemplateSectionDto = {id?: string | undefined, type?: string | undefined, content?: string | undefined, order?: (number | unknown) | undefined, columns?: (Array<TemplateSectionDto> | null) | undefined, widthPercent?: (number | unknown | null) | undefined};

export type RenderTemplatePreviewRequestDto = {sections?: Array<TemplateSectionDto> | undefined, format?: (string | null) | undefined, type?: (string | null) | undefined, category?: (string | null) | undefined, emailSubject?: (string | null) | undefined, emailBody?: (string | null) | undefined, smsBody?: (string | null) | undefined};

export type CreateApiTemplatesRenderPreviewArgs = {body: RenderTemplatePreviewRequestDto};

export type CreateApiTemplatesRenderPreviewOptions = {baseUrl?: string | undefined, Bearer?: string | undefined, fetch?: typeof fetch | undefined};

export const templatePreviewResultDto = z.object({pages: z.array(z.string()).optional(), pageCount: z.union([z.number().int(), z.string()]).optional(), widthMm: z.union([z.number(), z.string()]).optional(), heightMm: z.union([z.number(), z.string()]).optional(), dpi: z.union([z.number().int(), z.string()]).optional(), emailSubject: z.string().nullable().optional(), emailBody: z.string().nullable().optional(), smsBody: z.string().nullable().optional(), unknownVariables: z.array(z.string()).nullable().optional()});

export const validateResponse = async <Output>(
  schema: {
    readonly '~standard': {
      readonly validate: (value: unknown) => ({ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }) | Promise<{ readonly value: Output; readonly issues?: undefined } | { readonly issues: ReadonlyArray<{ readonly message: string; readonly path?: ReadonlyArray<PropertyKey | { readonly key: PropertyKey }> | undefined }> }>
    }
  },
  value: unknown
): Promise<Output> => {
  const result = await schema['~standard'].validate(value)

  if (result.issues !== undefined) {
    const detail = result.issues
      .map(({ message, path }) =>
        path?.length
          ? `${path.map((segment) => String(typeof segment === 'object' ? segment.key : segment)).join('.')}: ${message}`
          : message
      )
      .join('; ')

    throw new Error(`Response does not match the schema: ${detail}`, { cause: { issues: result.issues } })
  }

  return result.value
};

/**
 * Renders (possibly unsaved) editor sections through the real production
 * pipeline — sample data, regional compliance blocks, QuestPDF — and
 * returns one PNG per page. More than one page on a fixed-size label
 * format means the content overflows the label.
 * 
 * POST /templates/render-preview
 */
export const createApiTemplatesRenderPreview = async (args: CreateApiTemplatesRenderPreviewArgs, options?: CreateApiTemplatesRenderPreviewOptions) => {
const {baseUrl = "https://api.clinicos.vet/backend/business", fetch: fetchFn = fetch, Bearer} = options ?? {}

const query = new URLSearchParams()
const headers = new Headers()
headers.set('content-type', "application/json")
headers.set('accept', "application/json")

if (Bearer !== undefined) headers.set('authorization', `Bearer ${Bearer}`)

const url = `${baseUrl.replace(/\/+$/, '')}/templates/render-preview${query.size > 0 ? `?${query}` : ''}`

const res = await fetchFn(url, {method: "POST", headers, body: JSON.stringify(args.body)})

if (!res.ok) throw new Error(`Request failed with status ${res.status}`, {cause: {status: res.status, body: await res.text()}})

return validateResponse(templatePreviewResultDto, await res.json())
};