import { mkdtemp, rm, writeFile } from 'node:fs/promises'
import { tmpdir } from 'node:os'
import { join } from 'node:path'
import { pathToFileURL } from 'node:url'
import { afterEach, describe, expect, it } from 'vitest'
import { Context } from 'cordis'
import Loader from '@cordisjs/plugin-loader'
import Include from '@cordisjs/plugin-include'
import LlmService from '@deepseek-ai/dsh-llm'
import TokenMeterService from '@deepseek-ai/dsh-token-meter'
import BasicCompactService from '@deepseek-ai/dsh-compact-basic'

let root: string | undefined
let context: Context | undefined

afterEach(async () => {
  await context?.fiber.dispose()
  context = undefined
  if (root !== undefined) await rm(root, { recursive: true, force: true })
  root = undefined
})

describe('real Loader composition', () => {
  it('loads the zero-config token-meter then compact-basic YAML pair', async () => {
    root = await mkdtemp(join(tmpdir(), 'dsh-token-meter-loader-'))
    const configPath = join(root, 'cordis.yml')
    await writeFile(configPath, [
      "- name: '@deepseek-ai/dsh-llm'",
      "- name: '@deepseek-ai/dsh-token-meter'",
      "- name: '@deepseek-ai/dsh-compact-basic'",
      '',
    ].join('\n'))

    context = new Context()
    context.baseUrl = pathToFileURL(root).href + '/'
    await context.plugin(Loader)
    context.loader.builtins.include = Include
    const modules = new Map<string, unknown>([
      ['@deepseek-ai/dsh-llm', LlmService],
      ['@deepseek-ai/dsh-token-meter', TokenMeterService],
      ['@deepseek-ai/dsh-compact-basic', BasicCompactService],
    ])
    context.loader.internal = {
      version: 'v2',
      async import(specifier: string) {
        if (!modules.has(specifier)) throw new Error(`unexpected Loader import: ${specifier}`)
        return modules.get(specifier)
      },
    } as unknown as NonNullable<typeof context.loader.internal>
    await context.loader.create({
      name: 'cordis:include',
      config: { path: pathToFileURL(configPath).href },
    })
    await context.loader.await()

    const unloaded = [...context.loader.entries()]
      .filter(entry => entry.fiber === undefined && !entry.disabled)
      .map(entry => entry.options.name)
    expect(unloaded).toEqual([])
    expect(context.tokenMeter.resolve('deepseek-v4-flash')).toMatchObject({
      contextWindow: 128_000,
      charsPerToken: 4,
    })
    expect(context.get('compact')).toBeInstanceOf(BasicCompactService)
  })
})