package handler

import (
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"path/filepath"
	"strings"
	"testing"

	"github.com/agentmail/gateway/internal/db"
	"github.com/agentmail/gateway/internal/middleware"
	"github.com/agentmail/gateway/internal/models"
	"github.com/agentmail/gateway/internal/push"
)

/*
推送登记端点的判据（2026-09-15）。

用户的要求是「推送密钥应当是可选项」—— 自部署实例**没配推送**是常态。
所以这里钉住的是：**没配凭证时端点照样能用**（登记照存、回 enabled=false），
而不是"没配就报错"。客户端据此知道「登记成功了，但服务端现在没开推送」，
而不是把收不到通知当成登记失败去反复重试。

（本文件里的两个用例有先后依赖：先验「没配 = enabled:false」，再验「配了 = enabled:true」。
push 包的全局通道表只增不减，顺序反了前者会假红。）
*/

func setupPushHandlerDB(t *testing.T) {
	t.Helper()
	dir := t.TempDir()
	if err := db.Connect(context.Background(), "sqlite://"+filepath.Join(dir, "t.db")); err != nil {
		t.Fatalf("connect: %v", err)
	}
	if err := db.Migrate(context.Background()); err != nil {
		t.Fatalf("migrate: %v", err)
	}
	t.Cleanup(db.Close)
}

func pushReq(method, body, user string) *http.Request {
	var r *http.Request
	if body == "" {
		r = httptest.NewRequest(method, "/api/v1/me/devices/push-token", nil)
	} else {
		r = httptest.NewRequest(method, "/api/v1/me/devices/push-token", strings.NewReader(body))
	}
	if user != "" {
		r = r.WithContext(context.WithValue(r.Context(), middleware.UserKey, &models.User{Username: user}))
	}
	return r
}

func decodeBody(t *testing.T, rec *httptest.ResponseRecorder) map[string]any {
	t.Helper()
	var out map[string]any
	if err := json.Unmarshal(rec.Body.Bytes(), &out); err != nil {
		t.Fatalf("响应不是 JSON: %v（%s）", err, rec.Body.String())
	}
	return out
}

// 没配任何推送通道时：登记照存、回 enabled=false，且**不是错误**。
func TestPushTokenEndpointsWorkWithoutProviderCreds(t *testing.T) {
	setupPushHandlerDB(t)
	ctx := context.Background()

	rec := httptest.NewRecorder()
	RegisterPushToken(rec, pushReq(http.MethodPost,
		`{"provider":"hms","token":"tok-abc123456","device_name":"我的手机","session_id":"sess-1"}`, "alice"))
	if rec.Code != http.StatusOK {
		t.Fatalf("没配推送时登记也必须是 200（那是正常配置，不是故障），实际 %d: %s", rec.Code, rec.Body.String())
	}
	body := decodeBody(t, rec)
	if body["enabled"] != false {
		t.Fatalf("没配推送时应回 enabled=false，实际 %v", body["enabled"])
	}
	if body["ok"] != true {
		t.Fatalf("登记本身必须成功，实际 %v", body)
	}

	// GET 能列出来，且 token 只回尾 6 位（接口不该能读到 token 全文）
	rec = httptest.NewRecorder()
	ListPushTokens(rec, pushReq(http.MethodGet, "", "alice"))
	if rec.Code != http.StatusOK {
		t.Fatalf("GET 失败: %d", rec.Code)
	}
	body = decodeBody(t, rec)
	items, _ := body["tokens"].([]any)
	if len(items) != 1 {
		t.Fatalf("应列出 1 条登记，实际 %v", body["tokens"])
	}
	item, _ := items[0].(map[string]any)
	if item["token_tail"] != "123456" {
		t.Fatalf("token 应只回尾 6 位，实际 %v", item["token_tail"])
	}
	if _, leaked := item["token"]; leaked {
		t.Fatal("不该回 token 全文（多一处泄漏面）")
	}
	if item["session_id"] != "sess-1" || item["provider"] != "hms" {
		t.Fatalf("登记字段不对: %v", item)
	}

	// 别人看不到我的登记
	rec = httptest.NewRecorder()
	ListPushTokens(rec, pushReq(http.MethodGet, "", "bob"))
	if items, _ := decodeBody(t, rec)["tokens"].([]any); len(items) != 0 {
		t.Fatalf("bob 不该看到 alice 的登记: %v", items)
	}

	// 注销
	rec = httptest.NewRecorder()
	DeletePushToken(rec, pushReq(http.MethodDelete, `{"provider":"hms","token":"tok-abc123456"}`, "alice"))
	if rec.Code != http.StatusOK {
		t.Fatalf("注销失败: %d %s", rec.Code, rec.Body.String())
	}
	if removed, _ := decodeBody(t, rec)["deleted"].(bool); !removed {
		t.Fatal("注销应报告删到了行")
	}
	rec = httptest.NewRecorder()
	ListPushTokens(rec, pushReq(http.MethodGet, "", "alice"))
	if items, _ := decodeBody(t, rec)["tokens"].([]any); len(items) != 0 {
		t.Fatalf("注销后不该还有登记: %v", items)
	}
	_ = ctx
}

// 配了通道之后，同一个端点回 enabled=true 并报出通道名（客户端据此判断"现在能收到"）。
func TestPushTokenEndpointReportsEnabledProviders(t *testing.T) {
	setupPushHandlerDB(t)
	push.Register(fakeProviderForHandler{name: "hms"})

	rec := httptest.NewRecorder()
	RegisterPushToken(rec, pushReq(http.MethodPost, `{"provider":"hms","token":"tok-xyz"}`, "alice"))
	body := decodeBody(t, rec)
	if body["enabled"] != true {
		t.Fatalf("配了通道应回 enabled=true，实际 %v", body["enabled"])
	}
	providers, _ := body["providers"].([]any)
	if len(providers) != 1 || providers[0] != "hms" {
		t.Fatalf("providers 应含 hms，实际 %v", providers)
	}
}

type fakeProviderForHandler struct{ name string }

func (f fakeProviderForHandler) Name() string             { return f.name }
func (f fakeProviderForHandler) MaxTokensPerRequest() int { return 10 }
func (f fakeProviderForHandler) Send(context.Context, []string, push.NewMail) error {
	return nil
}

// 入参校验与鉴权。provider 只做**形状**校验（不做白名单：白名单会把"服务端还没实现的
// 那个通道"变成客户端的 400，而那恰恰是最不该拦的时候）。
func TestPushTokenEndpointInputValidation(t *testing.T) {
	setupPushHandlerDB(t)

	cases := []struct {
		name string
		body string
		user string
		want int
	}{
		{"未登录", `{"provider":"hms","token":"t"}`, "", http.StatusUnauthorized},
		{"provider 含大写", `{"provider":"HMS","token":"t"}`, "alice", http.StatusBadRequest},
		{"provider 为空", `{"provider":"","token":"t"}`, "alice", http.StatusBadRequest},
		{"provider 太长", `{"provider":"` + strings.Repeat("a", 33) + `","token":"t"}`, "alice", http.StatusBadRequest},
		{"token 为空", `{"provider":"hms","token":""}`, "alice", http.StatusBadRequest},
		{"token 超长", `{"provider":"hms","token":"` + strings.Repeat("a", 513) + `"}`, "alice", http.StatusBadRequest},
		{"未实现的新通道也收下", `{"provider":"webpush","token":"t"}`, "alice", http.StatusOK},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			rec := httptest.NewRecorder()
			RegisterPushToken(rec, pushReq(http.MethodPost, c.body, c.user))
			if rec.Code != c.want {
				t.Fatalf("%s: 期望 %d，实际 %d（%s）", c.name, c.want, rec.Code, rec.Body.String())
			}
		})
	}

	// DELETE 也要鉴权
	rec := httptest.NewRecorder()
	DeletePushToken(rec, pushReq(http.MethodDelete, `{"provider":"hms","token":"t"}`, ""))
	if rec.Code != http.StatusUnauthorized {
		t.Fatalf("未登录的注销应 401，实际 %d", rec.Code)
	}
}