import { afterAll, beforeAll, describe, expect, mock, test } from "bun:test"
import { mkdirSync, rmSync, symlinkSync, writeFileSync } from "node:fs"
import * as os from "node:os"
import { tmpdir } from "node:os"
import { join } from "node:path"

const originalHomedir = os.homedir.bind(os)
let mockedHomeDir = ""
let moduleImportCounter = 0
let resolvePromptAppend: typeof import("./resolve-file-uri").resolvePromptAppend

mock.module("node:os", () => ({
  ...os,
  homedir: () => mockedHomeDir || originalHomedir(),
}))

describe("resolvePromptAppend", () => {
  const fixtureRoot = join(tmpdir(), `resolve-file-uri-${Date.now()}`)
  const configDir = join(fixtureRoot, "config")
  const homeFixtureRoot = join(fixtureRoot, "home")
  const homeFixtureDir = join(homeFixtureRoot, "fixture-home")

  const absoluteFilePath = join(fixtureRoot, "absolute.txt")
  const relativeFilePath = join(configDir, "relative.txt")
  const spacedFilePath = join(fixtureRoot, "with space.txt")
  const homeFilePath = join(homeFixtureDir, "home.txt")
  const escapedFilePath = join(fixtureRoot, "escaped.txt")
  const linkedAbsolutePath = join(configDir, "linked-absolute.txt")

  beforeAll(async () => {
    mockedHomeDir = homeFixtureRoot
    mkdirSync(fixtureRoot, { recursive: true })
    mkdirSync(configDir, { recursive: true })
    mkdirSync(homeFixtureDir, { recursive: true })

    writeFileSync(absoluteFilePath, "absolute-content", "utf8")
    writeFileSync(relativeFilePath, "relative-content", "utf8")
    writeFileSync(spacedFilePath, "encoded-content", "utf8")
    writeFileSync(homeFilePath, "home-content", "utf8")
    writeFileSync(escapedFilePath, "escaped-content", "utf8")
    symlinkSync(absoluteFilePath, linkedAbsolutePath)

    moduleImportCounter += 1
    ;({ resolvePromptAppend } = await import(`./resolve-file-uri?test=${moduleImportCounter}`))
  })

  afterAll(() => {
    rmSync(fixtureRoot, { recursive: true, force: true })
    mock.restore()
  })

  test("returns non-file URI strings unchanged", () => {
    //#given
    const input = "append this text"

    //#when
    const resolved = resolvePromptAppend(input)

    //#then
    expect(resolved).toBe(input)
  })

  test("resolves absolute file URI to file contents", () => {
    //#given
    const input = `file://${absoluteFilePath}`

    //#when
    const resolved = resolvePromptAppend(input, fixtureRoot)

    //#then
    expect(resolved).toBe("absolute-content")
  })

  test("resolves relative file URI using configDir", () => {
    //#given
    const input = "file://./relative.txt"

    //#when
    const resolved = resolvePromptAppend(input, configDir)

    //#then
    expect(resolved).toBe("relative-content")
  })

  test("resolves home directory URI path", () => {
    //#given
    const input = "file://~/fixture-home/home.txt"

    //#when
    const resolved = resolvePromptAppend(input, homeFixtureRoot)

    //#then
    expect(resolved).toContain("[WARNING: Path rejected:")
  })

  test("resolves percent-encoded URI path", () => {
    //#given
    const input = `file://${encodeURIComponent(spacedFilePath)}`

    //#when
    const resolved = resolvePromptAppend(input, fixtureRoot)

    //#then
    expect(resolved).toBe("encoded-content")
  })

  test("returns warning for malformed percent-encoding", () => {
    //#given
    const input = "file://%E0%A4%A"

    //#when
    const resolved = resolvePromptAppend(input)

    //#then
    expect(resolved).toContain("[WARNING: Malformed file URI")
  })

  test("returns warning when file does not exist", () => {
    //#given
    const input = "file://./missing.txt"

    //#when
    const resolved = resolvePromptAppend(input, configDir)

    //#then
    expect(resolved).toContain("[WARNING: Could not resolve file URI")
  })

  test("rejects absolute file URI outside configDir", () => {
    //#given
    const input = `file://${absoluteFilePath}`

    //#when
    const resolved = resolvePromptAppend(input, configDir)

    //#then
    expect(resolved).toContain("[WARNING: Path rejected:")
    expect(resolved).not.toContain("absolute-content")
  })

  test("rejects traversal file URI that escapes configDir", () => {
    //#given
    const input = "file://../escaped.txt"

    //#when
    const resolved = resolvePromptAppend(input, configDir)

    //#then
    expect(resolved).toContain("[WARNING: Path rejected:")
    expect(resolved).not.toContain("escaped-content")
  })

  test("rejects symlink file URI that escapes configDir", () => {
    //#given
    const input = "file://./linked-absolute.txt"

    //#when
    const resolved = resolvePromptAppend(input, configDir)

    //#then
    expect(resolved).toContain("[WARNING: Path rejected:")
    expect(resolved).not.toContain("absolute-content")
  })
})