package handler

import (
	"errors"
	"testing"
)

// parseRelay 是免配额通道的入口校验。白名单 + 强制幂等键这两条必须守住：
// 前者防止 relay 变成任意字符串的后门，后者是「同一条上游消息只转一次」的基础。
func TestParseRelay(t *testing.T) {
	cases := []struct {
		name      string
		kind, key string
		wantKind  string
		wantKey   string
		wantErr   bool
	}{
		{name: "都为空 = 普通自主发信，正常扣配额", kind: "", key: "", wantKind: "", wantKey: ""},
		{name: "总结转发", kind: "summary", key: "msg_1", wantKind: "summary", wantKey: "msg_1"},
		{name: "权限转发", kind: "permission", key: "per_1", wantKind: "permission", wantKey: "per_1"},
		{name: "两端空白被裁掉", kind: "  summary ", key: " msg_2 ", wantKind: "summary", wantKey: "msg_2"},

		// 白名单外的类型必须拒：否则 relay:"anything" 就绕过了配额
		{name: "未知类型", kind: "whatever", key: "k", wantErr: true},
		// 没有幂等键就无法阻止同一条上游消息反复转发
		{name: "缺幂等键", kind: "summary", key: "", wantErr: true},
		{name: "只给了键没给类型", kind: "", key: "k", wantErr: true},
	}

	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			kind, key, err := parseRelay(c.kind, c.key)
			if c.wantErr {
				if err == nil {
					t.Fatalf("期望报错，实际通过：kind=%q key=%q", kind, key)
				}
				return
			}
			if err != nil {
				t.Fatalf("意外报错: %v", err)
			}
			if kind != c.wantKind || key != c.wantKey {
				t.Fatalf("得到 (%q, %q)，期望 (%q, %q)", kind, key, c.wantKind, c.wantKey)
			}
		})
	}
}

func TestParseRelayRejectsOverlongKey(t *testing.T) {
	long := make([]byte, 161)
	for i := range long {
		long[i] = 'k'
	}
	if _, _, err := parseRelay("summary", string(long)); err == nil {
		t.Fatal("超长 relay_key 应被拒绝（列宽 160）")
	}
}

// 免配额类型是白名单，不是黑名单。新增一种转发时必须同时更新这里，
// 免得悄悄多出一条不受审视的免费通道。
func TestRelayKindsIsExactlyTwo(t *testing.T) {
	want := map[string]bool{"permission": true, "summary": true}
	if len(relayKinds) != len(want) {
		t.Fatalf("免配额类型数量变了：%v。新增前请确认它确实是 harness 代劳而非模型自主发信", relayKinds)
	}
	for k := range want {
		if !relayKinds[k] {
			t.Fatalf("缺少免配额类型 %q", k)
		}
	}
}

// 报错必须是 400 而不是 500：这些都是调用方参数问题
func TestParseRelayErrorsAreBadRequest(t *testing.T) {
	for _, c := range [][2]string{{"whatever", "k"}, {"summary", ""}, {"", "k"}} {
		_, _, err := parseRelay(c[0], c[1])
		if err == nil {
			t.Fatalf("(%q,%q) 应报错", c[0], c[1])
		}
		var he httpError
		if !errors.As(err, &he) || he.status != 400 {
			t.Fatalf("(%q,%q) 的错误不是 400: %#v", c[0], c[1], err)
		}
	}
}