import {z} from 'zod'

export type ImageURL = {detail?: (string | null) | undefined, url: string};

export type MultiModalImageMessage = {image_url: ImageURL, type?: 'image_url' | undefined};

export type MultiModalTextMessage = {text: string, type?: 'text' | undefined};

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

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

export type ChatMessage = {content: string | Array<MultiModalImageMessage | MultiModalTextMessage> | null, role: string, tool_calls?: (Array<ToolCall> | null) | undefined};

export type ChatCompletionResponseFormat = {schema?: (Record<string, never> | null) | undefined, type: string};

export type StreamOptions = {include_usage?: boolean | undefined};

export type FunctionHandle = {name: string};

export type FunctionChoice = {function: FunctionHandle, type?: 'function' | undefined};

export type FunctionDefinition = {description?: string | undefined, name: string, parameters?: Record<string, never> | undefined};

export type ToolDefinition = {function: FunctionDefinition, type?: 'function' | undefined};

export type CreateChatCompletionRequest = {frequency_penalty?: number | undefined, ignore_eos?: boolean | undefined, log_prompt?: boolean | undefined, logit_bias?: ({[key: string]: number} | null) | undefined, loglikelihood?: boolean | undefined, logprobs?: boolean | undefined, max_tokens?: number | undefined, messages: Array<ChatMessage>, min_p?: number | undefined, model: string, n?: number | undefined, peft?: (string | null) | undefined, presence_penalty?: number | undefined, repetition_penalty?: number | undefined, response_format?: (ChatCompletionResponseFormat | null) | undefined, stop?: (string | Array<string> | null) | undefined, stream?: boolean | undefined, stream_options?: StreamOptions | undefined, temperature?: number | undefined, tool_choice?: ('auto' | 'required' | FunctionChoice | null) | undefined, tools?: (Array<ToolDefinition> | null) | undefined, top_logprobs?: number | undefined, top_p?: number | undefined, user?: (string | null) | undefined};

export type CreateApiV1ChatCompletionsArgs = {body: CreateChatCompletionRequest};

export type CreateApiV1ChatCompletionsOptions = {baseUrl?: string | undefined, fetch?: typeof fetch | undefined};

export const finishReason = z.enum(["stop", "length", "tool_calls", "content_filter", "function_call", "cancelled"]);

export const topLogprobs = z.object({bytes: z.array(z.unknown()).nullable().optional(), logprob: z.number(), token: z.string()});

export const logprobsContent = z.object({bytes: z.array(z.unknown()).nullable().optional(), logprob: z.number(), token: z.string(), top_logprobs: z.array(topLogprobs).optional()});

export const logprobs = z.object({content: z.array(logprobsContent.nullable()).optional()});

export const imageURL = z.object({detail: z.string().nullable().optional(), url: z.string()});

export const multiModalImageMessage = z.object({image_url: imageURL, type: z.literal("image_url").optional()});

export const multiModalTextMessage = z.object({text: z.string(), type: z.literal("text").optional()});

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

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

export const chatMessage = z.object({content: z.union([z.string(), z.array(z.discriminatedUnion("type", [multiModalImageMessage, multiModalTextMessage]))]).nullable(), role: z.string(), tool_calls: z.array(toolCall).nullable().optional()});

export const chatCompletionChoice = z.object({finish_reason: finishReason.nullable().optional(), index: z.number().int(), logprobs: logprobs.nullable().optional(), message: chatMessage});

export const usageStats = z.object({completion_tokens: z.number().int(), prompt_tokens: z.number().int(), total_tokens: z.number().int()});

export const chatCompletionResponse = z.object({choices: z.array(chatCompletionChoice), created: z.number().int(), id: z.string(), model: z.string(), object: z.literal("chat.completion").optional(), usage: usageStats});

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
};

/**
 * Create Chat Completion
 * 
 * POST /v1/chat/completions
 */
export const createApiV1ChatCompletions = async (args: CreateApiV1ChatCompletionsArgs, options?: CreateApiV1ChatCompletionsOptions) => {
const {baseUrl = "https://text.octoai.run", 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/chat/completions${query.size > 0 ? `?${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(chatCompletionResponse, await res.json())
};