import {z} from 'zod'

export type FunctionCall = {name: string, arguments: string};

export type ToolCall = {id?: string | undefined, type?: 'function' | undefined, function: FunctionCall};

export type CreateApiV1McpToolExecuteArgs = {body: ToolCall};

export type CreateApiV1McpToolExecuteOptions = {baseUrl?: string | undefined, fetch?: typeof fetch | undefined};

export const messageRole = z.enum(["user", "assistant", "system", "tool"]);

export const imageURLStruct = z.object({url: z.string(), detail: z.enum(["low", "high", "auto"]).optional()});

export const contentBlock = z.discriminatedUnion("type", [z.object({type: z.literal("text"), text: z.string()}), z.object({type: z.literal("image_url"), image_url: imageURLStruct})]);

export const functionCall = z.object({name: z.string(), arguments: z.string()});

export const toolCall = z.object({id: z.string().optional(), type: z.literal("function").optional(), function: functionCall});

export const citation = z.object({start_index: z.number().int(), end_index: z.number().int(), title: z.string(), url: z.string().optional(), sources: z.unknown(), type: z.string().optional()});

export const annotation = z.object({type: z.string(), url_citation: citation});

export const bifrostMessage = z.object({role: messageRole, content: z.union([z.string(), z.array(contentBlock)]).optional(), tool_call_id: z.string().optional(), tool_calls: z.array(toolCall).optional(), refusal: z.string().optional(), annotations: z.array(annotation).optional(), thought: z.string().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
};

/**
 * Execute MCP Tool
 * 
 * POST /v1/mcp/tool/execute
 */
export const createApiV1McpToolExecute = async (args: CreateApiV1McpToolExecuteArgs, options?: CreateApiV1McpToolExecuteOptions) => {
const {baseUrl = "http://localhost:8080", fetch: fetchFn = fetch} = options ?? {}

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

const url = `${baseUrl.replace(/\/+$/, '')}/v1/mcp/tool/execute${query.size > 0 ? `?${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(bifrostMessage, await res.json())
};