package main

import (
	"testing"
	"time"

	"chat-agent-system/internal/config"
)

// T20-B7 回归：drain 窗口与 AGENT_TIMEOUT 对齐。
func TestShutdownDrainTimeout_DefaultCapped35m(t *testing.T) {
	cfg := &config.Config{AgentTimeout: 60 * time.Minute} // 超过上限 → 封顶 35m
	got := shutdownDrainTimeout(cfg)
	want := 35*time.Minute + 30*time.Second
	if got != want {
		t.Fatalf("expect cap %s, got %s", want, got)
	}
}

func TestShutdownDrainTimeout_FollowsShortAgentTimeout(t *testing.T) {
	cfg := &config.Config{AgentTimeout: 10 * time.Minute} // 短于上限 → 跟随 +30s
	got := shutdownDrainTimeout(cfg)
	want := 10*time.Minute + 30*time.Second
	if got != want {
		t.Fatalf("expect %s, got %s", want, got)
	}
}

func TestShutdownDrainTimeout_EnvOverride(t *testing.T) {
	t.Setenv("SHUTDOWN_DRAIN_TIMEOUT", "45s")
	cfg := &config.Config{AgentTimeout: 30 * time.Minute}
	if got := shutdownDrainTimeout(cfg); got != 45*time.Second {
		t.Fatalf("env override expect 45s, got %s", got)
	}
}

func TestShutdownDrainTimeout_InvalidEnvFallsBack(t *testing.T) {
	t.Setenv("SHUTDOWN_DRAIN_TIMEOUT", "not-a-duration")
	cfg := &config.Config{AgentTimeout: 30 * time.Minute}
	want := 30*time.Minute + 30*time.Second
	if got := shutdownDrainTimeout(cfg); got != want {
		t.Fatalf("invalid env expect fallback %s, got %s", want, got)
	}
}

func TestShutdownDrainTimeout_NilCfg(t *testing.T) {
	got := shutdownDrainTimeout(nil)
	want := 30*time.Minute + 30*time.Second
	if got != want {
		t.Fatalf("nil cfg expect default %s, got %s", want, got)
	}
}