# Internal KVM Switch

FastAPI dashboard and polling service for Alienware-only KVM switching.

## Trigger Logic

The Samsung monitor is trigger-only and uses fixed input codes:

- Tower trigger: `15`
- Laptop trigger: `19`

Each installation of this tool is for one device only. The UI lets you choose:

- this device role: `tower` or `laptop`
- this device Alienware target port:

- `DP1`
- `DP2`
- `HDMI`

The device role can also still be provided by:

- environment variable `KVM_DEVICE_ROLE`
- or `config.json` field `device_role`

Valid values are:

- `tower`
- `laptop`

Examples:

- Tower role with UI port `DP1` -> on Samsung trigger `15`, send `DDM.exe /MNT:AW3423DWF /WriteActiveInput DP1`
- Laptop role with UI port `DP2` -> on Samsung trigger `19`, send `DDM.exe /MNT:AW3423DWF /WriteActiveInput DP2`

Retry behavior:

- Only attempts switching while the Samsung screen is connected
- After each switch attempt, waits `5` seconds and rechecks
- Tries at most `3` times per Samsung-connected session
- After success, it will not try again until the Samsung screen disconnects and reconnects

## Run

```powershell
uv run kvm-switch
```

The dashboard is served at `http://localhost:4000`.

## Test

```powershell
uv run pytest -q
```

## Diagnostic Script

Use this to inspect connected DDC/CI monitors and current input values:

```powershell
uv run monitorcontrol_main.py
```

## Autostart

### Easiest option: Startup folder

You can now set the role in the UI, so this step is optional.

If you prefer a default role before opening the dashboard, set it for that Windows user:

Tower machine:

```powershell
[System.Environment]::SetEnvironmentVariable("KVM_DEVICE_ROLE", "tower", "User")
```

Laptop machine:

```powershell
[System.Environment]::SetEnvironmentVariable("KVM_DEVICE_ROLE", "laptop", "User")
```

1. Press `Win + R`
2. Run:

```text
shell:startup
```

3. Create a shortcut in that folder pointing to:

```text
C:\Users\LagoWorkStation\OneDrive\Documentos\BE-terna\Internal - KVM Switch\start_kvm_switch_background.vbs
```

This starts the app at logon in the background (no persistent console window).

### Cleaner option: Task Scheduler

Use Task Scheduler if you want it to start automatically at logon with better control.

Program/script:

```text
wscript.exe
```

Arguments:

```text
"C:\Users\LagoWorkStation\OneDrive\Documentos\BE-terna\Internal - KVM Switch\start_kvm_switch_background.vbs"
```

Set the trigger to `At log on`. Optional: enable `Hidden` in task settings.