import { describe, expect, test } from "bun:test"
import path from "path"
import { InstructionPrompt } from "../../src/session/instruction"
import { Instance } from "../../src/project/instance"
import { tmpdir } from "../fixture/fixture"

describe("InstructionPrompt.resolve", () => {
  test("returns empty when AGENTS.md is at project root (already in systemPaths)", async () => {
    await using tmp = await tmpdir({
      init: async (dir) => {
        await Bun.write(path.join(dir, "AGENTS.md"), "# Root Instructions")
        await Bun.write(path.join(dir, "src", "file.ts"), "const x = 1")
      },
    })
    await Instance.provide({
      directory: tmp.path,
      fn: async () => {
        const system = await InstructionPrompt.systemPaths()
        expect(system.has(path.join(tmp.path, "AGENTS.md"))).toBe(true)

        const results = await InstructionPrompt.resolve([], path.join(tmp.path, "src", "file.ts"))
        expect(results).toEqual([])
      },
    })
  })

  test("returns AGENTS.md from subdirectory (not in systemPaths)", async () => {
    await using tmp = await tmpdir({
      init: async (dir) => {
        await Bun.write(path.join(dir, "subdir", "AGENTS.md"), "# Subdir Instructions")
        await Bun.write(path.join(dir, "subdir", "nested", "file.ts"), "const x = 1")
      },
    })
    await Instance.provide({
      directory: tmp.path,
      fn: async () => {
        const system = await InstructionPrompt.systemPaths()
        expect(system.has(path.join(tmp.path, "subdir", "AGENTS.md"))).toBe(false)

        const results = await InstructionPrompt.resolve([], path.join(tmp.path, "subdir", "nested", "file.ts"))
        expect(results.length).toBe(1)
        expect(results[0].filepath).toBe(path.join(tmp.path, "subdir", "AGENTS.md"))
      },
    })
  })
})