package accounts_test

import (
	"errors"
	"testing"

	"github.com/wangjia/pay/config"
	"github.com/wangjia/pay/internal/accounts"
)

func newReg() *accounts.Registry {
	return accounts.New([]config.AccountConfig{
		{AccountID: "f1", Channel: "fake", Region: "global", Enabled: true, Weight: 1},
		{AccountID: "f2", Channel: "fake", Region: "global", Enabled: true, Weight: 1},
		{AccountID: "f3", Channel: "fake", Region: "global", Enabled: false, Weight: 1}, // 禁用不参与
		{AccountID: "a1", Channel: "alipay", Region: "cn", Enabled: true, Weight: 1},
	})
}

func TestRouterDefaultRoundRobin(t *testing.T) {
	r := accounts.NewRouter(newReg(), nil, nil) // 无 routing → 默认 round_robin
	seq := []string{"f1", "f2", "f1"}
	for i, w := range seq {
		got, err := r.Pick("fake", "global", accounts.PickHint{OutTradeNo: "PAY-1"})
		if err != nil || got.AccountID != w {
			t.Fatalf("call %d got %v err %v want %s", i, got.AccountID, err, w)
		}
	}
}

func TestRouterExcludeSwitchesAccount(t *testing.T) {
	r := accounts.NewRouter(newReg(), map[string]string{"fake": accounts.StrategyWeighted}, nil)
	base, _ := r.Pick("fake", "global", accounts.PickHint{OutTradeNo: "PAY-RETRY"})
	// retry:排除首选账户 → 必换到另一个。
	got, err := r.Pick("fake", "global", accounts.PickHint{OutTradeNo: "PAY-RETRY", ExcludeAccounts: []string{base.AccountID}})
	if err != nil || got.AccountID == base.AccountID {
		t.Fatalf("排除 %s 后应换账户, got %v err %v", base.AccountID, got.AccountID, err)
	}
}

func TestRouterExcludeEmptyFallsBackToAll(t *testing.T) {
	r := accounts.NewRouter(newReg(), nil, nil)
	// alipay/cn 只有 a1;排除 a1 后候选空 → 回退全集,仍返回 a1(单账户 retry 不失败)。
	got, err := r.Pick("alipay", "cn", accounts.PickHint{OutTradeNo: "PAY-2", ExcludeAccounts: []string{"a1"}})
	if err != nil || got.AccountID != "a1" {
		t.Fatalf("排除到空应回退全集, got %v err %v", got.AccountID, err)
	}
}

func TestRouterNoAccount(t *testing.T) {
	r := accounts.NewRouter(newReg(), nil, nil)
	if _, err := r.Pick("wechat", "cn", accounts.PickHint{}); !errors.Is(err, accounts.ErrNoAccount) {
		t.Fatalf("无账户渠道应 ErrNoAccount, got %v", err)
	}
}