Below is a **clean implementation plan** for an **advanced interactive CLI** that supports:

1. **Arrow-key navigation**
2. **Enter to select**
3. **Clear multi-phase steps**

This is NOT the code template yet — only the *implementation plan* you asked for.

---

# ✅ **PHASE 1 — Foundation: Basic Interactive Shell**

Goal: keep the CLI running until user quits.

### Steps

1. Add entrypoint mode:

   * `mycli` → enter shell
   * `mycli <cmd>` → run once and exit

2. Create REPL loop:

   * print prompt
   * read user input
   * route to command handlers
   * handle errors without exiting the loop

3. Centralize command registry:

```
Map<String, Command> commands;
```

4. Add `help`, `exit`, `clear`.

Result: a stable, continuous CLI loop.

---

# ✅ **PHASE 2 — Add advanced input (arrow keys, selection menu)**

Goal: enable UI-like selection in terminal.

### Steps

1. Use **raw mode** for stdin:

   * turn off line buffering
   * capture arrow key escape codes
   * capture Enter, Ctrl+C

2. Build reusable "selector" component:

   * accepts a list of options
   * highlights current index
   * updates on arrow up/down
   * returns selected index when Enter is pressed

3. Add `MenuService`:

   * `selectBuildTarget()`
   * `selectFlavor()`
   * `selectCommand()`

4. Add rendering logic:

   * clear previous lines
   * redraw menu
   * maintain smooth UX on all platforms

Result: user can do:

```
> build
Select build target:
  > apk
    aab
    ipa
```

---

# ✅ **PHASE 3 — Command workflow (multi-step commands)**

Goal: some commands become step-by-step flows.

### Example: `build` flow

1. Ask for target → arrow keys
2. Ask for flavor → arrow keys
3. Ask for dart defines (optional input)
4. Confirm summary
5. Execute build

### Implementation plan

* Introduce a `FlowContext` that persists selected values
* Add `BuildFlow` class
* Use the menu selector for each step
* Allow "back", "skip", "cancel"

Result:

```
> build
Select build target:
  > apk
    aab

Select flavor:
  > dev
    prod

Build options summary:
  target: apk
  flavor: dev
Press Enter to confirm...
```

---

# ✅ **PHASE 4 — Shared runtime context**

Goal: load configs once, reuse everywhere.

### Steps

1. Create `AppContext`:

   * buildenv
   * pubspec info
   * project paths
   * environment flags

2. Load context only once at program start.

3. Pass context to:

   * REPL
   * menu selectors
   * command handlers
   * build/clean logic

Result: faster & cleaner CLI.

---

# ✅ **PHASE 5 — Polishing the experience**

Goal: behave like a professional CLI (Shorebird, Melos, Dart SDK).

### Add:

* color output + formatted sections

* spinners (while running tasks)

* keyboard shortcuts:

  * `q` → quit
  * `c` → cancel step
  * `←` (left arrow) → previous step

* persistent command history (optional)

* help panel

* banners, version, etc.

---

# ✅ **PHASE 6 — Packaging**

Goal: deliver a single binary.

### Steps

1. Compile:

```
dart compile exe bin/mycli.dart -o mycli
```

2. Distribute:

* Windows: `mycli.exe`
* macOS: `mycli`
* Linux: `mycli`

3. Optional installer:

* Homebrew tap
* Scoop bucket
* Apt package

---

# 📌 Final Overview (short)

| Phase | Goal                                    |
| ----- | --------------------------------------- |
| **1** | Continuous REPL loop                    |
| **2** | Arrow-key interactive menus             |
| **3** | Multi-step workflows (build wizard)     |
| **4** | Shared runtime context                  |
| **5** | UX polish (colors, spinners, shortcuts) |
| **6** | Compile & distribute binaries           |

---

If you want next step:

👉 **“give interactive template”**
I will generate a full working Dart template with:

* arrow-key menu system
* continuous shell
* clean architecture
* Windows/macOS/Linux support

Just say the command.
