import { describe, expect, test } from "bun:test"
import { OpenApi } from "effect/unstable/httpapi"
import { PublicApi } from "../../src/server/routes/instance/httpapi/public"

type Method = "get" | "post" | "put" | "delete" | "patch"
type OpenApiSchema = { readonly $ref?: string }
type OpenApiResponse = {
  readonly description?: string
  readonly content?: Record<string, { readonly schema?: OpenApiSchema }>
}
type OpenApiOperation = {
  readonly responses?: Record<string, OpenApiResponse>
  readonly security?: unknown
}
type OpenApiPathItem = Partial<Record<Method, OpenApiOperation>>
type OpenApiSpec = { readonly paths: Record<string, OpenApiPathItem> }

const methods = ["get", "post", "put", "delete", "patch"] as const

const allowedV2BuiltInEndpointErrors = [
  "GET /api/session 400 effect_HttpApiError_BadRequest",
  "GET /api/session/{sessionID}/message 400 effect_HttpApiError_BadRequest",
]

function v2Operations(spec: OpenApiSpec) {
  return Object.entries(spec.paths).flatMap(([path, item]) =>
    path.startsWith("/api/")
      ? methods.flatMap((method) => {
          const operation = item[method]
          return operation ? [{ method, path, operation }] : []
        })
      : [],
  )
}

function responseRef(response: OpenApiResponse | undefined) {
  return response?.content?.["application/json"]?.schema?.$ref
}

function componentName(ref: string) {
  return ref.replace("#/components/schemas/", "")
}

function isBuiltInEndpointError(name: string) {
  return name.startsWith("EffectHttpApiError") || name.startsWith("effect_HttpApiError_")
}

describe("PublicApi OpenAPI v2 errors", () => {
  test("preserves /api auth responses", () => {
    const spec = OpenApi.fromApi(PublicApi) as OpenApiSpec

    for (const route of v2Operations(spec)) {
      expect(route.operation.responses?.["401"], `${route.method.toUpperCase()} ${route.path}`).toBeDefined()
      expect(route.operation.security, `${route.method.toUpperCase()} ${route.path}`).toEqual([])
    }
  })

  test("does not rewrite /api endpoint errors to legacy error components", () => {
    const spec = OpenApi.fromApi(PublicApi) as OpenApiSpec
    const refs = v2Operations(spec)
      .flatMap((route) =>
        Object.entries(route.operation.responses ?? {}).flatMap(([status, response]) => {
          const ref = responseRef(response)
          return ref ? [`${route.method.toUpperCase()} ${route.path} ${status} ${componentName(ref)}`] : []
        }),
      )
      .filter((entry) => entry.includes("BadRequestError") || entry.includes("NotFoundError"))

    expect(refs).toEqual(["GET /api/provider/{providerID} 404 NotFoundError"])
  })

  test("new /api endpoint errors cannot use built-in components without an explicit allowlist", () => {
    const spec = OpenApi.fromApi(PublicApi) as OpenApiSpec
    const builtInEndpointErrors = v2Operations(spec)
      .flatMap((route) =>
        Object.entries(route.operation.responses ?? {}).flatMap(([status, response]) => {
          if (status === "401") return []
          const ref = responseRef(response)
          if (!ref) return []
          const name = componentName(ref)
          return isBuiltInEndpointError(name) ? [`${route.method.toUpperCase()} ${route.path} ${status} ${name}`] : []
        }),
      )
      .sort()

    expect(builtInEndpointErrors).toEqual(allowedV2BuiltInEndpointErrors)
  })
})