import {z} from 'zod'

export type FunctionParameters = {type?: string | undefined, properties: {[key: string]: Record<string, never>}, required: Array<string> | null};

export type ToolFunctionDetail = {name: string, description?: (string | null) | undefined, parameters: FunctionParameters};

export type ToolFunctionInput = {type?: 'function' | undefined, function: ToolFunctionDetail};

export type ToolChoiceFunction = {name: string};

export type ToolChoice = {type?: ('function' | 'json_object' | null) | undefined, function?: (ToolChoiceFunction | null) | undefined};

export type RequestResponseFormat = {type: 'text' | 'json_object'};

export type RoleContentChatChoiceContentImageUrl = {url: string};

export type RoleContentChatChoiceContent = {type: 'text' | 'image_url', text?: (string | null) | undefined, image_url?: (RoleContentChatChoiceContentImageUrl | null) | undefined};

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

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

export type RoleContentChatChoiceInput = {role: 'user' | 'assistant' | 'system', content: string | Array<RoleContentChatChoiceContent> | null, tool_calls?: (Array<ToolCall> | null) | undefined};

export type ChatCompletionRequestPayload = {model?: (string | null) | undefined, max_tokens?: (number | null) | undefined, temperature?: (number | null) | undefined, top_p?: (number | null) | undefined, tools?: (Array<ToolFunctionInput> | null) | undefined, tool_choice?: ('none' | 'auto' | ToolChoice) | undefined, n?: (number | null) | undefined, stream?: (boolean | null) | undefined, logprobs?: (number | null) | undefined, stop?: (string | Array<string> | null) | undefined, presence_penalty?: (number | null) | undefined, frequency_penalty?: (number | null) | undefined, best_of?: (number | null) | undefined, logit_bias?: (Record<string, never> | null) | undefined, response_format?: (RequestResponseFormat | null) | undefined, messages: Array<RoleContentChatChoiceInput>, plugins?: Array<string> | undefined};

export type CreateApiV1ChatCompletionsArgs = {body: ChatCompletionRequestPayload};

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

export const roleContentChatChoiceContentImageUrl = z.object({url: z.string()});

export const roleContentChatChoiceContent = z.object({type: z.enum(["text", "image_url"]), text: z.string().nullable().optional(), image_url: roleContentChatChoiceContentImageUrl.nullable().optional()});

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

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

export const roleContentChatChoiceOutput = z.object({role: z.enum(["user", "assistant", "system"]), content: z.union([z.string(), z.array(roleContentChatChoiceContent)]).nullable(), tool_calls: z.array(toolCall).nullable().optional()});

export const responseCompletionChatChoice = z.object({index: z.number().int(), finish_reason: z.string().nullable().optional(), message: roleContentChatChoiceOutput});

export const modelParts = z.object({model: z.string(), provider: z.string().nullable().optional(), owner: z.string().nullable().optional(), namespace: z.string(), at: z.string().nullable().optional()});

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

export const pulzeGeneratedArtifacts = z.object({items: z.array(z.object({})).optional()});

export const pulzeSearchResults = z.object({items: z.array(z.object({})).optional()});

export const rankedScoringModels = z.object({best_models: z.array(z.record(z.string(), z.number())).optional(), candidates: z.array(z.record(z.string(), z.number())).nullable().optional()});

export const pulzeEngineResponseMetadata = z.object({app_id: z.string().optional(), model: modelParts.nullable().optional(), costs: pulzeEngineTokens.optional(), cost_savings: pulzeEngineTokens.optional(), generated_artifacts: pulzeGeneratedArtifacts.optional(), search_results: pulzeSearchResults.optional(), latency: z.number().nullable().optional(), labels: z.record(z.string(), z.string()).nullable().optional(), error: z.string().nullable().optional(), scores: rankedScoringModels.nullable().optional(), score: z.number().nullable().optional(), temperature: z.union([z.number(), z.number().int()]).nullable().optional(), max_tokens: z.number().int().gte(-1).nullable().optional(), status_code: z.number().int().nullable().optional(), retries: z.number().int().optional(), extra: z.object({}).nullable().optional(), warning: z.string().nullable().optional()});

export const pulzeEngineResponseChatCompletion = z.object({choices: z.array(responseCompletionChatChoice), created: z.number().int().optional(), metadata: pulzeEngineResponseMetadata.optional(), id: z.string().optional(), usage: pulzeEngineTokens.optional(), model: z.string(), object: z.enum(["text_completion", "chat.completion"])}).and(z.record(z.string(), z.unknown()));

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
};

/**
 * Chat Completions
 * 
 * POST /v1/chat/completions
 */
export const createApiV1ChatCompletions = async (args: CreateApiV1ChatCompletionsArgs, options: CreateApiV1ChatCompletionsOptions) => {
const {baseUrl, fetch: fetchFn = fetch, HTTPBearer} = options ?? {}

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

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

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(pulzeEngineResponseChatCompletion, await res.json())
};