package main

import (
	"context"
	"testing"

	"github.com/google/uuid"
)

func TestExtractExecutionIDs(t *testing.T) {
	// Real tool-result phrasings that should yield an execution id.
	pos := map[string]string{
		`"pct_create on host:strong auto-approved via assent window — execution 019f4b19-eafd-74ed-baa6-d24a27b3f52c running."`: "019f4b19-eafd-74ed-baa6-d24a27b3f52c",
		`"run on lxc:caddy requires approval (risk: config_mutation) — execution 019f4af7-7eff-7723-b38c-b540b267f407 queued."`:   "019f4af7-7eff-7723-b38c-b540b267f407",
		`"apt_upgrade on host:hubris auto-approved via assent window — execution 019f4b58-c88c-7767-87dd-044608ced913 running."`:  "019f4b58-c88c-7767-87dd-044608ced913",
	}
	for in, want := range pos {
		ids := extractExecutionIDs(in)
		if len(ids) != 1 || ids[0].String() != want {
			t.Errorf("extractExecutionIDs(%q) = %v, want [%s]", in, ids, want)
		}
	}

	// Synchronous auto-run and read-only results carry no "execution <uuid>"
	// phrasing — they've already completed inline and must NOT be linked for
	// continuation.
	neg := []string{
		`"run on host:strong (read_only, auto): 09:30 up 8 days"`,
		`"run on lxc:caddy (config_mutation, auto via assent window): done"`,
		`[{"slug":"lxc:caddy","health":"healthy"}]`,
		`"target not found: lxc:nope"`,
	}
	for _, in := range neg {
		if ids := extractExecutionIDs(in); len(ids) != 0 {
			t.Errorf("extractExecutionIDs(%q) = %v, want none", in, ids)
		}
	}

	// De-dupes repeated ids in one result.
	dup := `execution 019f4b19-eafd-74ed-baa6-d24a27b3f52c queued ... execution 019f4b19-eafd-74ed-baa6-d24a27b3f52c running`
	if ids := extractExecutionIDs(dup); len(ids) != 1 {
		t.Errorf("expected de-dup to 1 id, got %v", ids)
	}
}

// TestResumeSession_SkipsWhenBusy guards the P0 fix
// (plans/2026-08-03-nomos-chat-changes-review.md): resumeSession must skip —
// return false, body never executed — when a turn is already active for the
// session. continueSession relies on this so it only marks a continuation
// "continued" after a turn really ran (otherwise the result is lost: marked
// continued, never re-queued by pendingContinuations).
//
// A minimal agent with only a gate is enough: if the body ever ran, chatWith
// would dereference the nil provider and panic. Returning false cleanly proves
// the body was skipped.
func TestResumeSession_SkipsWhenBusy(t *testing.T) {
	a := &agent{gate: newTurnGate()}
	if !a.gate.acquire("sess", 0) {
		t.Fatal("precondition: initial acquire should succeed on a free session")
	}
	ran := a.resumeSession(context.Background(), "sess", "note")
	if ran {
		t.Fatal("resumeSession must return false (skip) while a turn is active for the session")
	}
}

// TestContinueSession_DefersWhenBusy guards the other half of P0: when the
// session is busy, continueSession defers (leaves the execution pending for the
// next worker tick) instead of running or marking it. It must return cleanly
// without reaching resumeSession's body (nil provider → panic) or markContinued.
func TestContinueSession_DefersWhenBusy(t *testing.T) {
	a := &agent{gate: newTurnGate()}
	if !a.gate.acquire("sess", 0) {
		t.Fatal("precondition: initial acquire should succeed on a free session")
	}
	p := pendingContinuation{ExecID: uuid.New(), SessionID: "sess", Status: "completed"}
	a.continueSession(context.Background(), p) // must not panic; must not run/mark
}
