# reconciler_cli

An interactive REPL for exploring the reconciler module. Sets up a simulated three-resource state machine (device, transport, stream) with declared dependencies and lets you drive reconciliation manually — useful for understanding reconciler behaviour before wiring it into the node.

---

## Build

From the repository root:

```sh
make cli
```

The binary is placed in `build/cli/`.

---

## Usage

```sh
./reconciler_cli
```

Drops into an interactive prompt:

```
reconciler> _
```

### Demo resources

Three resources are pre-configured:

| Resource | States | Notes |
|---|---|---|
| `device` | CLOSED → OPEN → STREAMING | Simulates a V4L2 device |
| `transport` | DISCONNECTED → CONNECTED | Depends on device=OPEN |
| `stream` | INACTIVE → ACTIVE | Depends on transport=CONNECTED and device=STREAMING |

Dependencies are checked before each transition: the reconciler will not advance a resource until all its prerequisites are met. Blocked resources show the unmet dependency in the status output.

### Commands

```
status              print all resources with current/wanted state and transition status
want <name> <state> set the desired state (by number or case-insensitive name)
tick                run one reconciler tick
run                 tick until stable (max 20 ticks) or a failure occurs
fail <name>         make the next action for this resource fail (simulates an error)
help                show commands
quit / exit         exit
```

### Example session

```
reconciler> want device STREAMING
reconciler> want transport CONNECTED
reconciler> want stream ACTIVE
reconciler> run
[device]     CLOSED → OPEN          ok
[device]     OPEN → STREAMING       ok
[transport]  DISCONNECTED → CONNECTED  ok
[stream]     INACTIVE → ACTIVE      ok
reconciler> status
device     current=STREAMING  wanted=STREAMING
transport  current=CONNECTED  wanted=CONNECTED
stream     current=ACTIVE     wanted=ACTIVE
reconciler> fail transport
reconciler> tick
[transport]  CONNECTED → DISCONNECTED  error (simulated)
reconciler> status
device     current=STREAMING  wanted=STREAMING
transport  current=DISCONNECTED  wanted=CONNECTED   (will retry)
stream     current=ACTIVE     wanted=ACTIVE         (blocked: transport != CONNECTED)
```

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## Relationship to the Video Routing System

The reconciler module manages device open/close and transport connect/disconnect in the video node. `reconciler_cli` lets you exercise the BFS pathfinding, dependency checking, and event-driven tick logic without any real hardware — the same code paths that run in the node on every incoming command or timer event.