feat: 實作 bear CLI PAT 模式 MVP（login/whoami/token/logout/status）

- 新增 Elixir + Mix escript 專案（Req 0.5+、Jason） - login --token <PAT>：以 PAT 驗證 /userinfo 後寫入憑證檔（0600） - whoami：GET /userinfo 顯示身分 claims（支援 --json） - token：印出 access token 供 pipe（--refresh 在 PAT 模式忽略） - logout：清除本機憑證；status：純本機判定 - 憑證檔採原子寫入（rename）、0600、O_CREAT|O_EXCL 防 symlink - 全域選項：--issuer/--config/--json/-v/-h/--version - 29 個單元測試；mix precommit（compile --warnings-as-errors + format + test） - 更新 README.md 與 docs/commands.md 反映 PAT 模式 MVP Device Flow 登入待伺服器端 P1（bear 倉庫）完成後再接。issue #2
2026-08-30 14:24:51 +08:00
15 changed files with 1118 additions and 8 deletions
@@ -0,0 +1,3 @@
 [
  inputs: ["{mix,.formatter}.exs", "{config,lib,test}/**/*.{ex,exs}"]
 ]
@@ -8,6 +8,7 @@ erl_crash.dump
 *.ez
 bear-*.tar
 bear_cli-*.tar
 /bear
 /tmp/
 # 憑證與本機狀態（嚴禁進入版本庫）
@@ -2,7 +2,7 @@
 **Bear CLI** 是 [澳特科技](https://alterminal.com)（Alter Technology）單點登入系統 [Bear](https://gitea.alterminal.com/alterminal/bear) 的**終端機（CLI）客戶端**：讓使用者在 Linux 終端機直接以 Bear 帳號登入、查詢身分、取得並續期 Token，作為 SSO 的終端入口。
-> **狀態：規劃階段**。本倉庫目前只規劃指令介面（command spec），**尚未實作任何程式碼**。
+> **狀態：已實作 PAT 模式 MVP（Elixir + Req）**。`login --token <PAT>`、`whoami`、`token`、`logout`、`status` 已可用；Device Authorization Grant（RFC 8628）登入待伺服器端 P1（bear 倉庫）完成後再接。
 > 伺服器端採用的 OIDC **Device Authorization Grant（RFC 8628）** 方向，詳見 bear 倉庫的設計文件 `docs/cli-feature-plan.md`（issue #17）。
 ---
@@ -28,6 +28,33 @@ Bear 目前所有流程都依賴「瀏覽器」：登入 `/login`、儀表板 La
 ---
 ## 實作狀態（MVP）
 目前已實作**個人存取權杖（PAT）模式**的最小可用版本，涵蓋 P2 指令：
 | 指令 | 狀態 |
 |------|------|
 | `bear login --token <PAT>` | ✅ 已實作（PAT 模式；Device Flow 待伺服器端 P1） |
 | `bear whoami` | ✅ 已實作（`GET /userinfo`，Bearer PAT） |
 | `bear token` | ✅ 已實作（印出 PAT；`--refresh` 在 PAT 模式下無作用） |
 | `bear logout` | ✅ 已實作（清除本機憑證；PAT 需至網頁撤銷） |
 | `bear status` | ✅ 已實作（純本機判定） |
 | `bear apps` | ⏳ P3 暫緩 |
 ### 建置與執行
 ```bash
 mix deps.get          # 安裝依賴（Req、Jason）
 mix test              # 跑單元測試
 mix escript.build     # 產生單檔可執行 `bear`
 ./bear --help
 ./bear login --token <PAT> --issuer https://alterminal.com
 ```
 > 發行格式目前採 `mix escript`（目標機需 Erlang）；self-contained release（bakeware/burrito）仍為待定方向（見 `docs/commands.md` §7）。
 ---
 ## 全域選項
 | 選項 | 說明 | 預設 |
@@ -41,7 +68,18 @@ Bear 目前所有流程都依賴「瀏覽器」：登入 `/login`、儀表板 La
 ---
-## 登入流程（`bear login`，示意）
+## 登入流程（`bear login`）
 ### PAT 模式（現行）
 ```bash
 $ bear login --token <PAT>
 已登入：alice@example.com
 ```
 以個人存取權杖（PAT）直接驗證 `GET /userinfo`，成功後將 token 寫入本機憑證檔（0600）。全程免瀏覽器。
 ### Device Flow（待伺服器端 P1，示意）
 ```
 $ bear login
@@ -1,7 +1,7 @@
 # Bear CLI 指令規劃（Command Spec）
 > 狀態：規劃草案（對應 issue #19「創建 bear cli 倉庫」）
-> 範圍：**本文件只規劃指令介面，不實作程式碼**。
+> 實作：PAT 模式 MVP 已落地（issue #2），本文件為指令介面規格；Device Flow 待伺服器端 P1。
 > 登入採用的 OIDC Device Authorization Grant（RFC 8628）細節，見 bear 倉庫 `docs/cli-feature-plan.md`（issue #17）。
 ---
@@ -34,18 +34,27 @@
 ### 3.1 `bear login`
-啟動 Device Flow 登入，取得並保存 Token。
+登入並保存 Token。目前有兩種模式：
 - **PAT 模式（現行）**：`bear login --token <PAT>`，以個人存取權杖驗證 `GET /userinfo` 後保存 token，全程免瀏覽器。
 - **Device Flow（待 P1）**：`bear login`，啟動 Device Authorization Grant（RFC 8628），需伺服器端 P1 完成。
 ```
-bear login [--scope "openid profile email"] [--client-id ID]
+bear login [--token <PAT>] [--scope "openid profile email"] [--client-id ID]
 ```
 | 選項 | 預設 | 說明 |
 |------|------|------|
-| `--scope` | `openid profile email` | 請求的 scope（空白分隔） |
+| `--token` | — | PAT 模式：直接提供個人存取權杖（`-` 表示從 stdin 讀取） |
-| `--client-id` | 設定檔內值 | OIDC client id |
+| `--scope` | `openid profile email` | Device Flow：請求的 scope（空白分隔） |
 | `--client-id` | 設定檔內值 | Device Flow：OIDC client id |
-**行為**：
+**PAT 模式行為**：
 1. 向 `{issuer}/userinfo` 送 `Authorization: Bearer <PAT>` 驗證 token。
 2. 成功 → 寫入憑證檔（0600），印出 `已登入：<email>`；失敗（401）→ 印出錯誤，退出碼 `1`；網路錯誤 → 退出碼 `6`。
 **Device Flow 行為**：
 1. 讀取設定 → 向 `{issuer}/.well-known/openid-configuration` 取 `device_authorization_endpoint`（**動態發現，不寫死網址**）。
 2. `POST /device_authorization`（`client_id` + `scope`）。
@@ -225,3 +234,23 @@ bear apps
 | `token --refresh` | `POST /token`（refresh_token） |
 | `logout` | `POST /revoke` |
 | `apps`（P3） | 待新增「公開應用清單」API |
 ---
 ## 9. PAT 模式與原規格差異（現行實作）
 目前實作為 PAT 模式 MVP，與上方 Device Flow 規格有以下差異：
 | 指令 | 原規格（Device Flow） | PAT 模式現行行為 |
 |------|----------------------|------------------|
 | `login` | 裝置碼流程 | `--token <PAT>` 驗證 `/userinfo` 後保存 |
 | `whoami` | `GET /userinfo`（refresh 輪轉） | `GET /userinfo`（Bearer PAT，無輪轉） |
 | `token --refresh` | refresh token 輪轉換新 | 無 refresh token，`--refresh` 忽略並警告 |
 | `logout` | `POST /revoke`（撤銷 refresh token） | 僅清除本機憑證；PAT 需至網頁撤銷 |
 | `status` | 顯示 access token 剩餘秒數 | 顯示 PAT 模式與 issuer（PAT 無效期資訊） |
 憑證檔結構（PAT 模式）：
 ```json
 {"issuer": "https://alterminal.com", "access_token": "<PAT>", "email": "..."}
 ```
@@ -0,0 +1,14 @@
 defmodule BearCli do
  @moduledoc """
  Bear CLI — Bear SSO 的終端機客戶端。
  以 Bear 個人存取權杖（Personal Access Token, PAT）在終端機登入，查詢身分
  （`whoami`）、取得 Token（`token`），作為 SSO 的終端入口。Device
  Authorization Grant（RFC 8628）登入待伺服器端 P1（bear 倉庫）完成後再接上。
  """
  @version "0.1.0"
  @doc "回傳 CLI 版本字串（與 mix.exs 的 version 同步）。"
  def version, do: @version
 end
@@ -0,0 +1,54 @@
 defmodule BearCli.Api do
  @moduledoc """
  Bear 伺服器 HTTP 介面（一律使用 `Req`）。
  目前僅實作 PAT 模式所需的 `GET /userinfo`。
  """
  @finch BearCli.Finch
  @doc """
  呼叫 `GET {issuer}/userinfo`（Bearer token）。
  回傳：
    - `{:ok, claims}` — 200，claims 為 JSON map
    - `{:error, :unauthorized, description}` — 401
    - `{:error, :server_error, status}` — 其他非 2xx
    - `{:error, :network, reason}` — 傳輸層錯誤
  """
  def userinfo(issuer, token) do
    url = String.trim_trailing(issuer, "/") <> "/userinfo"
    case Req.get(url,
           headers: [authorization: "Bearer " <> token, accept: "application/json"],
           retry: false,
           finch: [name: @finch]
         ) do
      {:ok, %Req.Response{status: 200, body: body}} ->
        {:ok, decode_body(body)}
      {:ok, %Req.Response{status: 401, body: body}} ->
        {:error, :unauthorized, error_description(body)}
      {:ok, %Req.Response{status: status}} ->
        {:error, :server_error, status}
      {:error, exception} ->
        {:error, :network, Exception.message(exception)}
    end
  end
  defp decode_body(%{} = body), do: body
  defp decode_body(body) when is_binary(body), do: Jason.decode!(body)
  defp decode_body(_), do: %{}
  defp error_description(body) when is_binary(body) do
    case Jason.decode(body) do
      {:ok, %{"error_description" => desc}} when is_binary(desc) -> desc
      {:ok, %{"error" => err}} when is_binary(err) -> err
      _ -> "invalid_token"
    end
  end
  defp error_description(_), do: "invalid_token"
 end
@@ -0,0 +1,414 @@
 defmodule BearCli.CLI do
  @moduledoc """
  `bear` 指令的命令列入口與指令分派。
  支援指令：`login`（PAT 模式）、`whoami`、`token`、`logout`、`status`。
  """
  alias BearCli.{Api, Config, Credentials}
  @global_switches [
    issuer: :string,
    config: :string,
    json: :boolean,
    verbose: :boolean,
    help: :boolean,
    version: :boolean
  ]
  @global_aliases [v: :verbose, h: :help]
  @login_switches [token: :string, scope: :string, "client-id": :string]
  @token_switches [refresh: :boolean]
  # -- escript 入口 --
  @doc "escript 主函式。執行後以 `System.halt/1` 設定退出碼。"
  def main(argv) do
    start_apps()
    code = argv |> parse() |> dispatch()
    System.halt(code)
  end
  # Req 預設用 Finch 作為 HTTP adapter，escript 需自行啟動一個 pool。
  defp start_apps do
    _ = Application.ensure_all_started(:req)
    _ = Application.ensure_all_started(:finch)
    case Finch.start_link(name: BearCli.Finch) do
      {:ok, _} -> :ok
      {:error, _} -> :ok
    end
    :ok
  end
  # -- 解析 --
  @doc """
  解析 argv，回傳：
    - `{:version, opts}`
    - `{:help, opts}`
    - `{:ok, command, opts}`（opts 為 atom key 的 map）
    - `{:error, message, exit_code}`
  """
  def parse(argv) do
    argv = Enum.map(argv, &to_string/1)
    case OptionParser.parse_head(argv, strict: @global_switches, aliases: @global_aliases) do
      {global, rest, []} ->
        do_parse(global, rest)
      {_global, _rest, [{opt, _} | _]} ->
        {:error, "未知選項：#{opt}", 2}
    end
  end
  defp do_parse(global, rest) do
    cond do
      global[:version] ->
        {:version, %{}}
      global[:help] == true and rest == [] ->
        {:help, %{}}
      rest == [] ->
        {:help, %{}}
      true ->
        [command | args] = rest
        parse_command(command, args, global)
    end
  end
  defp parse_command("login", args, global) do
    with {:ok, opts} <- parse_opts(args, @global_switches ++ @login_switches) do
      {:ok, :login, merge_opts(global, opts)}
    end
  end
  defp parse_command("whoami", args, global) do
    with {:ok, opts} <- parse_opts(args, @global_switches) do
      {:ok, :whoami, merge_opts(global, opts)}
    end
  end
  defp parse_command("token", args, global) do
    with {:ok, opts} <- parse_opts(args, @global_switches ++ @token_switches) do
      {:ok, :token, merge_opts(global, opts)}
    end
  end
  defp parse_command("logout", args, global) do
    with {:ok, opts} <- parse_opts(args, @global_switches) do
      {:ok, :logout, merge_opts(global, opts)}
    end
  end
  defp parse_command("status", args, global) do
    with {:ok, opts} <- parse_opts(args, @global_switches) do
      {:ok, :status, merge_opts(global, opts)}
    end
  end
  defp parse_command(unknown, _args, _global) do
    {:error, "未知指令：#{unknown}（可用 bear --help 查看說明）", 2}
  end
  defp parse_opts(args, switches) do
    case OptionParser.parse(args, strict: switches) do
      {opts, [], []} ->
        {:ok, opts}
      {_opts, extra, []} ->
        {:error, "不接受的參數：#{Enum.join(extra, " ")}", 2}
      {_opts, _extra, [{opt, _} | _]} ->
        {:error, "無法解析選項：#{opt}", 2}
    end
  end
  defp merge_opts(global, opts) do
    Map.merge(Map.new(global), Map.new(opts))
  end
  # -- 分派 --
  @doc """
  執行已解析的指令，回傳退出碼。`opts[:api]` 可注入假的 userinfo 函式供測試。
  """
  def dispatch(parsed, opts \\ []) do
    api = opts[:api] || (&Api.userinfo/2)
    case parsed do
      {:version, _} ->
        IO.puts(BearCli.version())
        0
      {:help, _} ->
        print_help()
        0
      {:error, message, code} ->
        IO.puts(:stderr, "錯誤：#{message}")
        code
      {:ok, command, cmd_opts} ->
        cond do
          cmd_opts[:version] ->
            IO.puts(BearCli.version())
            0
          cmd_opts[:help] ->
            print_help()
            0
          true ->
            run(command, cmd_opts, api)
        end
    end
  end
  # -- 指令實作 --
  defp run(:login, opts, api) do
    case opts[:token] do
      nil ->
        IO.puts(:stderr, "Device Flow 登入尚未開放（伺服器端 P1 未實作）。")
        IO.puts(:stderr, "請改用個人存取權杖登入：bear login --token <PAT>")
        2
      "" ->
        fail(opts, "token 不可為空", 2)
      token ->
        token = if token == "-", do: read_token_from_stdin(), else: token
        do_login(opts, token, api)
    end
  end
  defp run(:whoami, opts, api) do
    case Credentials.load() do
      {:ok, creds} ->
        issuer = resolve_issuer(opts, creds["issuer"])
        token = creds["access_token"]
        if blank?(token) do
          fail(opts, "憑證檔缺少 access_token，請重新 bear login", 7)
        else
          if opts[:verbose], do: IO.puts(:stderr, "issuer: #{issuer}")
          case api.(issuer, token) do
            {:ok, claims} ->
              if opts[:json] do
                IO.puts(Jason.encode!(%{ok: true, claims: claims}))
              else
                print_claims(claims)
              end
              0
            {:error, :unauthorized, desc} ->
              fail(opts, "token 無效或已過期（#{desc}），請重新 bear login", 1)
            {:error, :network, reason} ->
              fail(opts, "無法連線到 #{issuer}：#{reason}", 6)
            {:error, :server_error, status} ->
              fail(opts, "伺服器回應 #{status}", 6)
          end
        end
      :error ->
        fail(opts, "未登入（請先執行 bear login）", 3)
    end
  end
  defp run(:token, opts, _api) do
    case Credentials.load() do
      {:ok, creds} ->
        if opts[:refresh] do
          IO.puts(:stderr, "警告：PAT 模式無 refresh token，--refresh 已忽略。")
        end
        case creds["access_token"] do
          token when is_binary(token) and token != "" ->
            # token 指令只輸出 token 本體（單行、無前綴），供 pipe 使用。
            IO.puts(token)
            0
          _ ->
            fail_token("憑證檔缺少 access_token，請重新 bear login", 7)
        end
      :error ->
        fail_token("未登入（請先執行 bear login）", 3)
    end
  end
  defp run(:logout, opts, _api) do
    case Credentials.delete() do
      :ok ->
        if opts[:json] do
          IO.puts(Jason.encode!(%{ok: true}))
        else
          IO.puts("已登出（本機憑證已清除）。")
          IO.puts("注意：PAT 本身仍在伺服器端有效，如需撤銷請至 Bear 網頁「個人存取權杖」頁面。")
        end
        0
      {:error, reason} ->
        fail(opts, "清除憑證失敗：#{inspect(reason)}", 1)
    end
  end
  defp run(:status, opts, _api) do
    case Credentials.load() do
      {:ok, creds} ->
        if opts[:json] do
          IO.puts(
            Jason.encode!(%{
              ok: true,
              logged_in: true,
              email: creds["email"],
              issuer: creds["issuer"],
              mode: "pat"
            })
          )
        else
          IO.puts("已登入：#{creds["email"] || "(未知)"}")
          IO.puts("模式：個人存取權杖（PAT）")
          IO.puts("issuer：#{creds["issuer"]}")
        end
        0
      :error ->
        if opts[:json] do
          IO.puts(Jason.encode!(%{ok: false, logged_in: false, error: "未登入", code: 3}))
        else
          IO.puts("未登入")
        end
        3
    end
  end
  # -- 指令實作輔助 --
  defp do_login(opts, token, api) do
    issuer = resolve_issuer(opts)
    if opts[:verbose], do: IO.puts(:stderr, "issuer: #{issuer}")
    case api.(issuer, token) do
      {:ok, claims} ->
        email = claims["email"]
        creds = %{"issuer" => issuer, "access_token" => token, "email" => email}
        case Credentials.save(creds) do
          :ok ->
            if opts[:json] do
              IO.puts(Jason.encode!(%{ok: true, email: email}))
            else
              IO.puts("已登入：#{email || "(無 email claim)"}")
            end
            0
          {:error, reason} ->
            fail(opts, "憑證檔寫入失敗：#{inspect(reason)}", 1)
        end
      {:error, :unauthorized, desc} ->
        fail(opts, "token 無效或已過期（#{desc}）", 1)
      {:error, :network, reason} ->
        fail(opts, "無法連線到 #{issuer}：#{reason}", 6)
      {:error, :server_error, status} ->
        fail(opts, "伺服器回應 #{status}", 6)
    end
  end
  # -- 輔助 --
  # 優先取 --issuer flag；否則取憑證內記錄的 issuer；最後才回落 config/env/預設。
  defp resolve_issuer(opts, stored_issuer \\ nil) do
    opts[:issuer] || stored_issuer || Config.resolve_issuer(nil, opts[:config])
  end
  defp read_token_from_stdin do
    IO.read(:stdio, :line) |> to_string() |> String.trim()
  end
  defp fail(opts, message, code) do
    if opts[:json] do
      IO.puts(Jason.encode!(%{ok: false, error: message, code: code}))
    else
      IO.puts(:stderr, "錯誤：#{message}")
    end
    code
  end
  # token 指令的錯誤一律走 stderr，避免污染 stdout（pipe 的對象）。
  defp fail_token(message, code) do
    IO.puts(:stderr, "錯誤：#{message}")
    code
  end
  @preferred_claims ~w(sub email name preferred_username nickname picture)
  defp print_claims(claims) do
    preferred =
      Enum.filter(@preferred_claims, &Map.has_key?(claims, &1))
    rest =
      claims
      |> Map.drop(@preferred_claims)
      |> Enum.sort_by(fn {k, _} -> to_string(k) end)
    Enum.each(preferred, fn k ->
      IO.puts("#{String.pad_trailing(k, 20)}: #{format_value(claims[k])}")
    end)
    Enum.each(rest, fn {k, v} ->
      IO.puts("#{String.pad_trailing(to_string(k), 20)}: #{format_value(v)}")
    end)
  end
  defp format_value(v) when is_binary(v), do: v
  defp format_value(v) when is_number(v), do: to_string(v)
  defp format_value(v) when is_boolean(v), do: to_string(v)
  defp format_value(v) when is_nil(v), do: ""
  defp format_value(v), do: Jason.encode!(v)
  defp blank?(nil), do: true
  defp blank?(""), do: true
  defp blank?(_), do: false
  defp print_help do
    IO.puts("""
    Bear CLI — Bear SSO 終端機客戶端
    用法：bear <指令> [選項]
    指令：
      login --token <PAT>   以個人存取權杖登入（PAT 模式；Device Flow 尚未開放）
      whoami                顯示目前登入身分
      token [--refresh]     印出 access token（PAT 模式下 --refresh 為無作用）
      logout                登出（清除本機憑證）
      status                顯示登入狀態
    全域選項：
      --issuer URL          Bear（OIDC Provider）位址（預設 https://alterminal.com）
      --config PATH         設定檔路徑（預設 ~/.config/bear/config.json）
      --json                機器可讀輸出（JSON）
      -v, --verbose         顯示詳細日誌
      -h, --help            顯示說明
      --version             顯示版本
    """)
  end
 end
@@ -0,0 +1,84 @@
 defmodule BearCli.Config do
  @moduledoc """
  設定檔與憑證檔的路徑及讀取。
  設定優先序：CLI flag ＞ 環境變數（`BEAR_ISSUER`）＞ 設定檔 ＞ 內建預設。
  """
  @default_issuer "https://alterminal.com"
  @doc "內建預設 issuer。"
  def default_issuer, do: @default_issuer
  @doc """
  設定檔路徑：`~/.config/bear/config.json`（可用 `BEAR_CONFIG` 覆寫）。
  """
  def config_path do
    System.get_env("BEAR_CONFIG") || Path.join(config_home(), "config.json")
  end
  @doc """
  憑證檔路徑：`~/.local/state/bear/credentials.json`（可用 `BEAR_CREDENTIALS` 覆寫）。
  """
  def credentials_path do
    System.get_env("BEAR_CREDENTIALS") || Path.join(state_home(), "credentials.json")
  end
  defp config_home do
    base =
      System.get_env("XDG_CONFIG_HOME") ||
        Path.join(System.user_home!(), ".config")
    Path.join(base, "bear")
  end
  defp state_home do
    base =
      System.get_env("XDG_STATE_HOME") ||
        Path.join(System.user_home!(), ".local/state")
    Path.join(base, "bear")
  end
  @doc """
  讀取設定檔，回傳 `{:ok, map}` 或 `:error`（檔案不存在／JSON 損毀）。
  """
  def read_config(path \\ config_path()) do
    case File.read(path) do
      {:ok, content} -> Jason.decode(content)
      {:error, _} -> :error
    end
  end
  @doc """
  解析最終 issuer，依序取第一個非空白值：
  1. `cli_issuer`（`--issuer` flag）
  2. `BEAR_ISSUER` 環境變數
  3. 設定檔的 `issuer` 欄位（讀自 `config_path_override` 或預設路徑）
  4. 內建預設 `https://alterminal.com`
  """
  def resolve_issuer(cli_issuer, config_path_override \\ nil) do
    path = config_path_override || config_path()
    config =
      case read_config(path) do
        {:ok, map} when is_map(map) -> map
        _ -> %{}
      end
    Enum.find(
      [
        cli_issuer,
        System.get_env("BEAR_ISSUER"),
        config["issuer"],
        @default_issuer
      ],
      &(not blank?(&1))
    )
  end
  defp blank?(nil), do: true
  defp blank?(""), do: true
  defp blank?(_), do: false
 end
@@ -0,0 +1,87 @@
 defmodule BearCli.Credentials do
  @moduledoc """
  本機憑證檔的讀寫（0600，原子寫入、防 symlink 攻擊）。
  憑證檔結構（JSON）：
      {"issuer": "https://alterminal.com", "access_token": "<PAT>", "email": "..."}
  PAT 模式沒有 refresh token，`access_token` 即個人存取權杖本身。
  """
  alias BearCli.Config
  @doc """
  載入憑證，回傳 `{:ok, map}` 或 `:error`（不存在／JSON 損毀）。
  """
  def load(path \\ Config.credentials_path()) do
    case File.read(path) do
      {:ok, content} ->
        case Jason.decode(content) do
          {:ok, map} when is_map(map) -> {:ok, map}
          _ -> :error
        end
      {:error, _} ->
        :error
    end
  end
  @doc """
  寫入憑證（原子、0600）。建立父目錄（0700）。回傳 `:ok` 或 `{:error, reason}`。
  """
  def save(map, path \\ Config.credentials_path()) do
    json = Jason.encode!(map)
    with :ok <- ensure_parent_dir(path),
         {:ok, tmp} <- write_temp(path, json) do
      # rename(2) 會原子地取代目標（包含取代 symlink 本身，而非其指向的檔案）。
      File.rename(tmp, path)
    else
      {:error, _} = error -> error
    end
  end
  @doc """
  刪除憑證檔；檔案不存在也算成功。
  """
  def delete(path \\ Config.credentials_path()) do
    case File.rm(path) do
      :ok -> :ok
      {:error, :enoent} -> :ok
      {:error, reason} -> {:error, reason}
    end
  end
  defp ensure_parent_dir(path) do
    dir = Path.dirname(path)
    File.mkdir_p(dir)
    # 目錄權限 0700 為 best-effort（例如憑證路徑落在 /tmp 等共享目錄時無法 chmod，
    # 忽略即可；真正的保護是憑證檔本身的 0600）。
    _ = File.chmod(dir, 0o700)
    :ok
  end
  defp write_temp(path, json) do
    dir = Path.dirname(path)
    tmp = Path.join(dir, ".credentials.#{System.unique_integer([:positive])}.tmp")
    result =
      with {:ok, io} <- File.open(tmp, [:write, :exclusive, :binary]),
           :ok <- IO.binwrite(io, json),
           :ok <- File.close(io),
           :ok <- File.chmod(tmp, 0o600) do
        {:ok, tmp}
      end
    case result do
      {:ok, _} = ok ->
        ok
      {:error, _} = error ->
        _ = File.rm(tmp)
        error
    end
  end
 end
@@ -0,0 +1,49 @@
 defmodule BearCli.MixProject do
  use Mix.Project
  def project do
    [
      app: :bear_cli,
      version: "0.1.0",
      elixir: "~> 1.17",
      start_permanent: Mix.env() == :prod,
      deps: deps(),
      escript: escript(),
      aliases: aliases()
    ]
  end
  def application do
    [
      extra_applications: [:logger]
    ]
  end
  def cli do
    [
      preferred_envs: [precommit: :test]
    ]
  end
  # escript 打包：單檔可執行，主模組為 BearCli.CLI。
  defp escript do
    [
      main_module: BearCli.CLI,
      name: "bear"
    ]
  end
  defp deps do
    [
      # HTTP 一律使用 Req（與 bear 主專案一致）。
      {:req, "~> 0.5"},
      {:jason, "~> 1.2"}
    ]
  end
  defp aliases do
    [
      precommit: ["compile --warnings-as-errors", "format", "test"]
    ]
  end
 end
@@ -0,0 +1,11 @@
 %{
  "finch": {:hex, :finch, "0.23.0", "e3f9287ac25a8832f848b144c2b57346aac65b205e2e0629a52adfe6507fd837", [:mix], [{:mime, "~> 1.0 or ~> 2.0", [hex: :mime, repo: "hexpm", optional: false]}, {:mint, "~> 1.8", [hex: :mint, repo: "hexpm", optional: false]}, {:nimble_options, "~> 0.4 or ~> 1.0", [hex: :nimble_options, repo: "hexpm", optional: false]}, {:nimble_pool, "~> 1.1", [hex: :nimble_pool, repo: "hexpm", optional: false]}, {:telemetry, "~> 0.4 or ~> 1.0", [hex: :telemetry, repo: "hexpm", optional: false]}], "hexpm", "80e58d3f936f57e3fdf404f83a3642897ae6d9fb642934e46da4d8fe761b99d5"},
  "hpax": {:hex, :hpax, "1.0.4", "777de5d433b0fbdc7c418159c8055910faa8047ffdb3d6b31098d2a46cd7685c", [:mix], [], "hexpm", "afc7cb142ebcc2d01ce7816190b98ce5dd49e799111b24249f3443d730f377ca"},
  "jason": {:hex, :jason, "1.4.5", "2e3a008590b0b8d7388c20293e9dcc9cf3e5d642fd2a114e4cbbb52e595d940a", [:mix], [{:decimal, "~> 1.0 or ~> 2.0 or ~> 3.0", [hex: :decimal, repo: "hexpm", optional: true]}], "hexpm", "b0c823996102bcd0239b3c2444eb00409b72f6a140c1950bc8b457d836b30684"},
  "mime": {:hex, :mime, "2.0.7", "b8d739037be7cd402aee1ba0306edfdef982687ee7e9859bee6198c1e7e2f128", [:mix], [], "hexpm", "6171188e399ee16023ffc5b76ce445eb6d9672e2e241d2df6050f3c771e80ccd"},
  "mint": {:hex, :mint, "1.9.3", "3337184d69179695c7a9f1714d92c11e629d36c8c037a21cf490131d3d150554", [:mix], [{:castore, "~> 0.1.0 or ~> 1.0", [hex: :castore, repo: "hexpm", optional: true]}, {:hpax, "~> 0.1.1 or ~> 0.2.0 or ~> 1.0", [hex: :hpax, repo: "hexpm", optional: false]}], "hexpm", "5f7c9342480c069dbbc4eeac3490303c9e01870ff01a7f1d29b6107054fc1e74"},
  "nimble_options": {:hex, :nimble_options, "1.1.1", "e3a492d54d85fc3fd7c5baf411d9d2852922f66e69476317787a7b2bb000a61b", [:mix], [], "hexpm", "821b2470ca9442c4b6984882fe9bb0389371b8ddec4d45a9504f00a66f650b44"},
  "nimble_pool": {:hex, :nimble_pool, "1.1.0", "bf9c29fbdcba3564a8b800d1eeb5a3c58f36e1e11d7b7fb2e084a643f645f06b", [:mix], [], "hexpm", "af2e4e6b34197db81f7aad230c1118eac993acc0dae6bc83bac0126d4ae0813a"},
  "req": {:hex, :req, "0.7.4", "23e9ffec17de032a46a4b15ed65c09793893bf4a7c680f4bbf6227fce6bdf74d", [:mix], [{:brotli, "~> 0.3.1", [hex: :brotli, repo: "hexpm", optional: true]}, {:finch, "~> 0.21", [hex: :finch, repo: "hexpm", optional: false]}, {:jason, "~> 1.0", [hex: :jason, repo: "hexpm", optional: false]}, {:mime, "~> 2.0.6 or ~> 2.1", [hex: :mime, repo: "hexpm", optional: false]}, {:nimble_csv, "~> 1.0", [hex: :nimble_csv, repo: "hexpm", optional: true]}, {:plug, "~> 1.0", [hex: :plug, repo: "hexpm", optional: true]}], "hexpm", "4b192d63253e8dcc6221ef992ea9ebef7d3555166e8423aa5b553e86bc3c69a2"},
  "telemetry": {:hex, :telemetry, "1.4.2", "a0cb522801dffb1c49fe6e30561badffc7b6d0e180db1300df759faa22062855", [:rebar3], [], "hexpm", "928f6495066506077862c0d1646609eed891a4326bee3126ba54b60af61febb1"},
 }
@@ -0,0 +1,200 @@
 defmodule BearCli.CLITest do
  use ExUnit.Case, async: false
  alias BearCli.CLI
  setup do
    old_creds = System.get_env("BEAR_CREDENTIALS")
    on_exit(fn ->
      restore_env("BEAR_CREDENTIALS", old_creds)
    end)
    :ok
  end
  describe "parse/1" do
    test "no args -> help" do
      assert {:help, %{}} = CLI.parse([])
    end
    test "--version" do
      assert {:version, %{}} = CLI.parse(["--version"])
    end
    test "-h alias -> help" do
      assert {:help, %{}} = CLI.parse(["-h"])
    end
    test "login --token X" do
      assert {:ok, :login, %{token: "X"}} = CLI.parse(["login", "--token", "X"])
    end
    test "global option before command" do
      assert {:ok, :whoami, %{json: true}} = CLI.parse(["--json", "whoami"])
    end
    test "global option after command" do
      assert {:ok, :status, %{json: true}} = CLI.parse(["status", "--json"])
    end
    test "token --refresh" do
      assert {:ok, :token, %{refresh: true}} = CLI.parse(["token", "--refresh"])
    end
    test "issuer flag is captured" do
      assert {:ok, :whoami, %{issuer: "https://x"}} =
               CLI.parse(["whoami", "--issuer", "https://x"])
    end
    test "unknown command -> usage error" do
      assert {:error, _, 2} = CLI.parse(["frobnicate"])
    end
    test "unknown option -> usage error" do
      assert {:error, _, 2} = CLI.parse(["--bogus"])
    end
  end
  describe "dispatch/2 (injected api)" do
    test "login --token writes credentials and prints email" do
      path = tmp_path()
      on_exit(fn -> File.rm(path) end)
      System.put_env("BEAR_CREDENTIALS", path)
      {code, out} =
        ExUnit.CaptureIO.with_io(fn ->
          CLI.dispatch(CLI.parse(["login", "--token", "good"]), api: fake_api())
        end)
      assert code == 0
      assert out =~ "已登入：alice@example.com"
      assert {:ok, %{"access_token" => "good"}} = BearCli.Credentials.load(path)
    end
    test "login with invalid token exits 1" do
      System.put_env("BEAR_CREDENTIALS", tmp_path())
      {code, err} =
        ExUnit.CaptureIO.with_io(
          :stderr,
          "",
          fn -> CLI.dispatch(CLI.parse(["login", "--token", "bad"]), api: fake_api()) end
        )
      assert code == 1
      assert err =~ "token 無效"
    end
    test "login without --token points to Device Flow being unavailable" do
      System.put_env("BEAR_CREDENTIALS", tmp_path())
      {code, err} =
        ExUnit.CaptureIO.with_io(
          :stderr,
          "",
          fn -> CLI.dispatch(CLI.parse(["login"]), api: fake_api()) end
        )
      assert code == 2
      assert err =~ "Device Flow"
    end
    test "whoami when not logged in exits 3" do
      System.put_env("BEAR_CREDENTIALS", "/nonexistent/credentials.json")
      {code, err} =
        ExUnit.CaptureIO.with_io(
          :stderr,
          "",
          fn -> CLI.dispatch(CLI.parse(["whoami"]), api: fake_api()) end
        )
      assert code == 3
      assert err =~ "未登入"
    end
    test "whoami prints claims" do
      path = tmp_path()
      on_exit(fn -> File.rm(path) end)
      System.put_env("BEAR_CREDENTIALS", path)
      BearCli.Credentials.save(%{"issuer" => "https://x", "access_token" => "good"}, path)
      {code, out} =
        ExUnit.CaptureIO.with_io(fn ->
          CLI.dispatch(CLI.parse(["whoami"]), api: fake_api())
        end)
      assert code == 0
      assert out =~ "email"
      assert out =~ "alice@example.com"
    end
    test "token prints only the token" do
      path = tmp_path()
      on_exit(fn -> File.rm(path) end)
      System.put_env("BEAR_CREDENTIALS", path)
      BearCli.Credentials.save(%{"issuer" => "https://x", "access_token" => "good-token"}, path)
      {code, out} =
        ExUnit.CaptureIO.with_io(fn ->
          CLI.dispatch(CLI.parse(["token"]), api: fake_api())
        end)
      assert code == 0
      assert String.trim(out) == "good-token"
    end
    test "status when logged in exits 0 and reports PAT mode" do
      path = tmp_path()
      on_exit(fn -> File.rm(path) end)
      System.put_env("BEAR_CREDENTIALS", path)
      BearCli.Credentials.save(
        %{"issuer" => "https://x", "email" => "a@b.c", "access_token" => "t"},
        path
      )
      {code, out} =
        ExUnit.CaptureIO.with_io(fn ->
          CLI.dispatch(CLI.parse(["status"]), api: fake_api())
        end)
      assert code == 0
      assert out =~ "已登入：a@b.c"
      assert out =~ "PAT"
    end
    test "logout clears credentials" do
      path = tmp_path()
      on_exit(fn -> File.rm(path) end)
      System.put_env("BEAR_CREDENTIALS", path)
      BearCli.Credentials.save(%{"issuer" => "https://x", "access_token" => "t"}, path)
      {code, _out} =
        ExUnit.CaptureIO.with_io(fn ->
          CLI.dispatch(CLI.parse(["logout"]), api: fake_api())
        end)
      assert code == 0
      assert :error == BearCli.Credentials.load(path)
    end
  end
  defp fake_api do
    fn _issuer, token ->
      case token do
        "good" -> {:ok, %{"sub" => "u1", "email" => "alice@example.com", "name" => "Alice"}}
        "bad" -> {:error, :unauthorized, "invalid_token"}
        _ -> {:error, :server_error, 500}
      end
    end
  end
  defp tmp_path do
    Path.join(System.tmp_dir!(), "bear_cli_cli_#{System.unique_integer([:positive])}.json")
  end
  defp restore_env(key, nil), do: System.delete_env(key)
  defp restore_env(key, value), do: System.put_env(key, value)
 end
@@ -0,0 +1,63 @@
 defmodule BearCli.ConfigTest do
  use ExUnit.Case, async: false
  alias BearCli.Config
  @nonexistent "/nonexistent/bear_cli_config.json"
  setup do
    old_issuer = System.get_env("BEAR_ISSUER")
    old_config = System.get_env("BEAR_CONFIG")
    on_exit(fn ->
      restore_env("BEAR_ISSUER", old_issuer)
      restore_env("BEAR_CONFIG", old_config)
    end)
    System.delete_env("BEAR_ISSUER")
    System.put_env("BEAR_CONFIG", @nonexistent)
    :ok
  end
  test "defaults to the built-in issuer when nothing else is set" do
    assert Config.resolve_issuer(nil) == "https://alterminal.com"
  end
  test "CLI flag takes precedence over everything" do
    System.put_env("BEAR_ISSUER", "https://env.example.com")
    assert Config.resolve_issuer("https://flag.example.com") == "https://flag.example.com"
  end
  test "BEAR_ISSUER env wins over config and default" do
    System.put_env("BEAR_ISSUER", "https://env.example.com")
    assert Config.resolve_issuer(nil) == "https://env.example.com"
  end
  test "config file issuer wins over default" do
    path = write_config(%{"issuer" => "https://config.example.com"})
    on_exit(fn -> File.rm(path) end)
    assert Config.resolve_issuer(nil, path) == "https://config.example.com"
  end
  test "config path override is honored" do
    path = write_config(%{"issuer" => "https://override.example.com"})
    on_exit(fn -> File.rm(path) end)
    assert Config.resolve_issuer(nil, path) == "https://override.example.com"
  end
  defp write_config(map) do
    path =
      Path.join(System.tmp_dir!(), "bear_cli_config_#{System.unique_integer([:positive])}.json")
    File.write!(path, Jason.encode!(map))
    path
  end
  defp restore_env(key, nil), do: System.delete_env(key)
  defp restore_env(key, value), do: System.put_env(key, value)
 end
@@ -0,0 +1,62 @@
 defmodule BearCli.CredentialsTest do
  use ExUnit.Case, async: true
  alias BearCli.Credentials
  test "save/load round-trips JSON" do
    path = tmp_path()
    on_exit(fn -> File.rm(path) end)
    assert :ok ==
             Credentials.save(
               %{"issuer" => "x", "access_token" => "tok", "email" => "a@b.c"},
               path
             )
    assert {:ok, %{"access_token" => "tok", "email" => "a@b.c"}} = Credentials.load(path)
  end
  test "save creates the file with 0600 permissions" do
    path = tmp_path()
    on_exit(fn -> File.rm(path) end)
    :ok = Credentials.save(%{"access_token" => "tok"}, path)
    mode = File.stat!(path).mode
    assert Bitwise.band(mode, 0o777) == 0o600
  end
  test "save creates the parent directory" do
    base = Path.join(System.tmp_dir!(), "bear_cli_nested_#{System.unique_integer([:positive])}")
    path = Path.join([base, "sub", "credentials.json"])
    on_exit(fn -> File.rm_rf(base) end)
    :ok = Credentials.save(%{"a" => "b"}, path)
    assert File.regular?(path)
  end
  test "load returns :error for a missing file" do
    assert :error == Credentials.load("/nonexistent/credentials.json")
  end
  test "load returns :error for corrupt JSON" do
    path = tmp_path()
    on_exit(fn -> File.rm(path) end)
    File.write!(path, "{not json")
    assert :error == Credentials.load(path)
  end
  test "delete removes the file and is idempotent" do
    path = tmp_path()
    on_exit(fn -> File.rm(path) end)
    :ok = Credentials.save(%{"a" => "b"}, path)
    assert :ok == Credentials.delete(path)
    assert :error == Credentials.load(path)
    assert :ok == Credentials.delete(path)
  end
  defp tmp_path do
    Path.join(System.tmp_dir!(), "bear_cli_creds_#{System.unique_integer([:positive])}.json")
  end
 end
@@ -0,0 +1 @@
 ExUnit.start()