package httpapi

import (
	"fmt"
	"net/http"
	"strings"
	"testing"
)

// TestVisibilityMatrix 核心不变量（§13）：主体 × 笔记状态 × 出口 的表驱动矩阵。
// 判定规则：匿名不可见 ⇒ 404 或输出中不含。
func TestVisibilityMatrix(t *testing.T) {
	e := newEnv(t)
	f := e.fixtures()

	type outlet struct {
		name  string
		probe func(c *http.Client, subject string) (status int, body string)
	}

	contains := func(body, sub string) bool { return strings.Contains(body, sub) }

	outlets := []outlet{
		{
			name: "列表/api/notes",
			probe: func(c *http.Client, _ string) (int, string) {
				resp, b := e.get(c, "/api/notes?page_size=100")
				return resp.StatusCode, string(b)
			},
		},
		{
			name: "详情/api/notes/{slug}",
			probe: func(c *http.Client, slug string) (int, string) {
				resp, b := e.get(c, "/api/notes/"+slug)
				return resp.StatusCode, string(b)
			},
		},
		{
			name: "标签/api/tags",
			probe: func(c *http.Client, _ string) (int, string) {
				resp, b := e.get(c, "/api/tags")
				return resp.StatusCode, string(b)
			},
		},
		{
			name: "RSS/feed.xml",
			probe: func(c *http.Client, _ string) (int, string) {
				resp, b := e.get(c, "/feed.xml")
				return resp.StatusCode, string(b)
			},
		},
		{
			name: "sitemap.xml",
			probe: func(c *http.Client, _ string) (int, string) {
				resp, b := e.get(c, "/sitemap.xml")
				return resp.StatusCode, string(b)
			},
		},
		{
			name: "HTML meta 注入",
			probe: func(c *http.Client, slug string) (int, string) {
				resp, b := e.get(c, "/notes/"+slug)
				return resp.StatusCode, string(b)
			},
		},
	}

	// (出口, 状态特征, 匿名期望, 管理员期望)
	type expect struct {
		anonVisible  bool
		adminVisible bool
	}
	notes := []struct {
		slug    string
		title   string
		tag     string
		visible expect
	}{
		{f.pubSlug, "公开笔记Alpha", "公开", expect{true, true}},
		{f.privSlug, "私有笔记Beta", "秘密", expect{false, false}}, // 管理员也只在详情/admin 出口可见
		{f.trashSlug, "回收站笔记Gamma", "公开", expect{false, false}},
		{"no-such-note", "不存在笔记", "无", expect{false, false}},
	}

	for _, n := range notes {
		for _, o := range outlets {
			t.Run(o.name+"/"+n.slug, func(t *testing.T) {
				statusAnon, bodyAnon := o.probe(f.anon, n.slug)
				statusAdmin, bodyAdmin := o.probe(f.admin, n.slug)

				if statusAnon >= 500 || statusAdmin >= 500 {
					t.Fatalf("5xx: anon=%d admin=%d", statusAnon, statusAdmin)
				}
				// 详情出口：非公开匿名必须 404；HTML meta 出口走 SPA fallback（200），
				// 按 §13 用「输出中不含」判定（下方 meta 内容断言）
				isDetail := strings.Contains(o.name, "详情")
				isMeta := strings.Contains(o.name, "meta")
				// 匿名判定
				if isDetail {
					if n.visible.anonVisible {
						if statusAnon != http.StatusOK {
							t.Errorf("匿名应可见但状态 %d", statusAnon)
						}
					} else if statusAnon != http.StatusNotFound {
						t.Errorf("匿名不可见应为 404，实际 %d（body: %.100s）", statusAnon, bodyAnon)
					}
				} else if !isMeta {
					if !n.visible.anonVisible && (contains(bodyAnon, n.title) || contains(bodyAnon, n.slug)) {
						t.Errorf("匿名输出中不应出现 %q/%q", n.title, n.slug)
					}
				}
				// meta 注入内容判定：公开 → 注入笔记标题；非公开匿名 → 站点默认标题
				if strings.Contains(o.name, "meta") {
					if n.visible.anonVisible {
						if !contains(bodyAnon, "<title>"+n.title) {
							t.Errorf("公开笔记 meta 应注入笔记标题，body: %s", bodyAnon)
						}
					} else {
						if contains(bodyAnon, n.title) {
							t.Errorf("非公开笔记 meta 不应注入笔记标题")
						}
						if !contains(bodyAnon, "<title>测试站</title>") {
							t.Errorf("非公开笔记 meta 应回退站点默认标题，body: %s", bodyAnon)
						}
					}
				}
				// 管理员判定：列表/标签/RSS/sitemap 仍只含公开内容
				if strings.Contains(o.name, "列表") || strings.Contains(o.name, "标签") ||
					strings.Contains(o.name, "RSS") || strings.Contains(o.name, "sitemap") {
					if contains(bodyAdmin, n.title) && !n.visible.anonVisible {
						t.Errorf("管理员的公开聚合出口（%s）也不应包含非公开内容 %q", o.name, n.title)
					}
				}
				// 详情：管理员可读公开+私有，不可读回收站/不存在
				if isDetail {
					switch {
					case n.slug == f.pubSlug:
						if statusAdmin != http.StatusOK || !contains(bodyAdmin, `"status":"public"`) {
							t.Errorf("管理员读公开笔记失败: %d", statusAdmin)
						}
					case n.slug == f.privSlug:
						if statusAdmin != http.StatusOK || !contains(bodyAdmin, `"status":"private"`) {
							t.Errorf("管理员应可私有预览: %d body: %.200s", statusAdmin, bodyAdmin)
						}
					default:
						if statusAdmin != http.StatusNotFound {
							t.Errorf("管理员读 %s 应 404（回收站仅经 /api/admin/trash），实际 %d", n.slug, statusAdmin)
						}
					}
				}
			})
		}
	}

	// ---- 图片出口（并集语义 + 缓存头分流，§6.2/§7.4）----
	imageCases := []struct {
		name        string
		id          int64
		anonCode    int
		anonCache   string
		adminCode   int
		adminCache  string
	}{
		{"公开图", f.imgPub, 200, "public, max-age=31536000, immutable", 200, "public, max-age=31536000, immutable"},
		{"私有图", f.imgPriv, 404, "", 200, "private, no-store"},
		{"回收站图", f.imgTrash, 404, "", 200, "private, no-store"},
		{"孤儿图", f.imgOrphan, 404, "", 200, "private, no-store"},
		{"不存在图", 99999, 404, "", 404, ""},
	}
	for _, ic := range imageCases {
		t.Run("图片/"+ic.name, func(t *testing.T) {
			path := "/api/images/" + fmt.Sprint(ic.id)
			respA, _ := e.get(f.anon, path)
			if respA.StatusCode != ic.anonCode {
				t.Errorf("匿名期望 %d 实际 %d", ic.anonCode, respA.StatusCode)
			}
			if ic.anonCache != "" && respA.Header.Get("Cache-Control") != ic.anonCache {
				t.Errorf("匿名缓存头期望 %q 实际 %q", ic.anonCache, respA.Header.Get("Cache-Control"))
			}
			respM, _ := e.get(f.admin, path)
			if respM.StatusCode != ic.adminCode {
				t.Errorf("管理员期望 %d 实际 %d", ic.adminCode, respM.StatusCode)
			}
			if ic.adminCache != "" && respM.Header.Get("Cache-Control") != ic.adminCache {
				t.Errorf("管理员缓存头期望 %q 实际 %q", ic.adminCache, respM.Header.Get("Cache-Control"))
			}
			// 统一 404 不泄露存在性：私有与不存在响应体一致
			if ic.anonCode == 404 {
				_, b1 := e.get(f.anon, path)
				_, b2 := e.get(f.anon, "/api/images/99998")
				if string(b1) != string(b2) {
					t.Errorf("404 响应体应统一（防枚举）: %q vs %q", b1, b2)
				}
			}
		})
	}

	// ---- 管理接口权限 ----
	t.Run("管理接口权限", func(t *testing.T) {
		for _, tc := range []struct {
			method, path string
		}{
			{http.MethodGet, "/api/admin/notes"},
			{http.MethodGet, "/api/admin/trash"},
			{http.MethodGet, "/api/admin/settings"},
		} {
			resp, _ := e.get(f.anon, tc.path)
			if resp.StatusCode != http.StatusUnauthorized {
				t.Errorf("匿名 %s %s 应 401，实际 %d", tc.method, tc.path, resp.StatusCode)
			}
			respM, _ := e.get(f.admin, tc.path)
			if respM.StatusCode != http.StatusOK {
				t.Errorf("管理员 %s %s 应 200，实际 %d", tc.method, tc.path, respM.StatusCode)
			}
		}
		// 回收站内容仅经 /api/admin/trash 可见
		resp, body := e.get(f.admin, "/api/admin/trash")
		if resp.StatusCode != 200 || !contains(string(body), "回收站笔记Gamma") {
			t.Errorf("回收站列表应包含已删笔记: %d %s", resp.StatusCode, body)
		}
	})
}