import type { Config, Redacted } from "effect"
import * as OpenAICompatibleChat from "../protocols/openai-compatible-chat"
import { Auth } from "../route/auth"
import { AuthOptions, type AtLeastOne, type ProviderAuthOption } from "../route/auth-options"
import type { RouteDefaultsInput } from "../route/client"
import { ProviderID, type ModelID } from "../schema"

export const aiGatewayID = ProviderID.make("cloudflare-ai-gateway")
export const workersAIID = ProviderID.make("cloudflare-workers-ai")
export const aiGatewayAuthEnvVars = ["CLOUDFLARE_API_TOKEN", "CF_AIG_TOKEN"] as const
export const workersAIAuthEnvVars = ["CLOUDFLARE_API_KEY", "CLOUDFLARE_WORKERS_AI_TOKEN"] as const

type CloudflareSecret = string | Redacted.Redacted | Config.Config<string | Redacted.Redacted>

type GatewayURL = AtLeastOne<{
  readonly accountId: string
  readonly baseURL: string
}> & {
  readonly gatewayId?: string
}

export type AIGatewayOptions = GatewayURL &
  RouteDefaultsInput &
  ProviderAuthOption<"optional"> & {
    /** Cloudflare AI Gateway authentication token. Sent as `cf-aig-authorization`. */
    readonly gatewayApiKey?: CloudflareSecret
  }

type WorkersAIURL = AtLeastOne<{
  readonly accountId: string
  readonly baseURL: string
}>

export type WorkersAIOptions = WorkersAIURL & RouteDefaultsInput & ProviderAuthOption<"optional">

export const aiGatewayBaseURL = (input: GatewayURL) => {
  if (input.baseURL) return input.baseURL
  if (!input.accountId) throw new Error("CloudflareAIGateway.configure requires accountId unless baseURL is supplied")
  return `https://gateway.ai.cloudflare.com/v1/${encodeURIComponent(input.accountId)}/${encodeURIComponent(input.gatewayId?.trim() || "default")}/compat`
}

const aiGatewayAuth = (input: AIGatewayOptions) => {
  if ("auth" in input && input.auth) return input.auth
  const gateway = Auth.optional(input.gatewayApiKey, "gatewayApiKey")
    .orElse(Auth.config("CLOUDFLARE_API_TOKEN"))
    .orElse(Auth.config("CF_AIG_TOKEN"))
    .pipe(Auth.bearerHeader("cf-aig-authorization"))
  if (!("apiKey" in input) || input.apiKey === undefined) return gateway
  if (input.gatewayApiKey === undefined) return Auth.bearer(input.apiKey)
  return Auth.bearerHeader("cf-aig-authorization", input.gatewayApiKey).andThen(Auth.bearer(input.apiKey))
}

export const workersAIBaseURL = (input: WorkersAIURL) => {
  if (input.baseURL) return input.baseURL
  if (!input.accountId) throw new Error("CloudflareWorkersAI.configure requires accountId unless baseURL is supplied")
  return `https://api.cloudflare.com/client/v4/accounts/${encodeURIComponent(input.accountId)}/ai/v1`
}

const workersAIAuth = (input: WorkersAIOptions) => {
  return AuthOptions.bearer(input, workersAIAuthEnvVars)
}

export const aiGatewayRoute = OpenAICompatibleChat.route.with({
  id: "cloudflare-ai-gateway",
  provider: aiGatewayID,
})

export const workersAIRoute = OpenAICompatibleChat.route.with({
  id: "cloudflare-workers-ai",
  provider: workersAIID,
})

export const routes = [aiGatewayRoute, workersAIRoute]

const aiGatewayDefaults = (options: AIGatewayOptions) => {
  const {
    accountId: _accountId,
    gatewayId: _gatewayId,
    apiKey: _apiKey,
    gatewayApiKey: _gatewayApiKey,
    baseURL: _baseURL,
    auth: _auth,
    ...rest
  } = options
  return rest
}

const workersAIDefaults = (options: WorkersAIOptions) => {
  const { accountId: _accountId, apiKey: _apiKey, auth: _auth, baseURL: _baseURL, ...rest } = options
  return rest
}

const configureAIGateway = (options: AIGatewayOptions) => {
  const route = aiGatewayRoute.with({
    ...aiGatewayDefaults(options),
    endpoint: { baseURL: aiGatewayBaseURL(options) },
    auth: aiGatewayAuth(options),
  })
  return {
    id: aiGatewayID,
    model: (modelID: string | ModelID) => route.model({ id: modelID }),
    configure: configureAIGateway,
  }
}

const configureWorkersAI = (options: WorkersAIOptions) => {
  const route = workersAIRoute.with({
    ...workersAIDefaults(options),
    endpoint: { baseURL: workersAIBaseURL(options) },
    auth: workersAIAuth(options),
  })
  return {
    id: workersAIID,
    model: (modelID: string | ModelID) => route.model({ id: modelID }),
    configure: configureWorkersAI,
  }
}

export const CloudflareAIGateway = {
  id: aiGatewayID,
  configure: configureAIGateway,
}

export const CloudflareWorkersAI = {
  id: workersAIID,
  configure: configureWorkersAI,
}