// Agent with persistent memory via remember()/recall().
// Demonstrates: the remember/recall builtins backed by a [persistent] slot,
// a knowledge-base lifecycle, and recall() returning () for unknown keys
// (null-checked with ??).
//
// Run:  SOMA_LLM_MOCK=echo soma run memory_agent.cell --signal learn "capital" "Paris"
// Test: SOMA_LLM_MOCK=echo soma test memory_agent.cell

cell agent Librarian {
    face {
        signal learn(key: String, value: String) -> Map
        signal lookup(key: String) -> String
        signal answer(question: String) -> Map
    }

    memory {
        kb: Map<String, String> [persistent]
    }

    state task {
        initial: idle
        idle    -> working
        working -> done
        *       -> failed
    }

    on learn(key: String, value: String) {
        remember(key, value)
        kb.set(key, value)
        map("stored", key, "value", value)
    }

    on lookup(key: String) {
        let v = recall(key)
        v ?? "unknown"
    }

    on answer(question: String) {
        set_budget(2000)
        let id = to_string(next_id())
        transition(id, "working")
        let r = try { think("Answer using stored facts: {question}") }
        if r.error != () {
            transition(id, "failed")
            return map("status", "failed", "error", r.error)
        }
        transition(id, "done")
        map("status", "done", "answer", r.value)
    }
}

cell test LibrarianTests {
    rules {
        assert learn("capital", "Paris").stored == "capital"
        assert lookup("capital") == "Paris"
        // recall on an unknown key falls back via ??.
        assert lookup("nope") == "unknown"
        assert answer("hi").status == "done"
    }
}