package gateway

import (
	"bytes"
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/auth"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/config"
	"git.yeij.top/AskaEth/Cyrene_v2/internal/config/runtimeconfig"
)

// 本文件覆盖渠道级角色绑定的管理侧一半（design/22 §2
// 方案 b / §4.4）：PUT /admin/channels/{platform}/config 通过
// 既有的 read-modify-write + bridge.Reload 路径接受 personaId，
// 未知角色会被拒绝，而不是绑定一个无法应答的角色；
// 列表端点会回报该绑定。
//
// personaId 在线上是三态的，因为面板仅在主人
// 真正触碰过角色选择时才发送该键：
//
//	键缺失       → 保留已存绑定
//	显式 ""      → 清除绑定
//	非空 id      → 绑定该角色（未知 id → 400）
//
// 「键缺失」这一情形正是静默丢弃绑定的那个，因此用字面量
// JSON 请求体断言：若 DTO 从别处取到了值，map[string]any
// 仍会让断言通过。

// putChannelConfigRaw 发送字面量 JSON 请求体，使测试能钉死确切的
// 线上结构（尤其是：完全没有 personaId 键）。
func putChannelConfigRaw(t *testing.T, ts *httptest.Server, platform, raw, token string) (*http.Response, []byte) {
	t.Helper()
	req, err := http.NewRequest(http.MethodPut,
		ts.URL+"/api/v1/admin/channels/"+platform+"/config", bytes.NewReader([]byte(raw)))
	if err != nil {
		t.Fatalf("new request: %v", err)
	}
	req.Header.Set("Authorization", "Bearer "+token)
	req.Header.Set("Content-Type", "application/json")
	resp, err := http.DefaultClient.Do(req)
	if err != nil {
		t.Fatalf("do request: %v", err)
	}
	defer resp.Body.Close()
	b, err := io.ReadAll(resp.Body)
	if err != nil {
		t.Fatalf("read response: %v", err)
	}
	if resp.StatusCode != http.StatusCreated {
		t.Fatalf("PUT %s status = %d, want 201 (body=%s)", platform, resp.StatusCode, b)
	}
	return resp, b
}

// storedPersonaID 读取 channels.json 为某个账号保存的绑定。
func storedPersonaID(t *testing.T, path, platform, accountID string) string {
	t.Helper()
	accounts, warn := runtimeconfig.LoadChannels(path, nil)
	if warn != nil {
		t.Fatalf("load channels warn = %v", warn)
	}
	for _, acct := range accounts[platform] {
		if acct.ID == accountID {
			return acct.PersonaID
		}
	}
	t.Fatalf("account %s/%s not found in channels.json: %+v", platform, accountID, accounts[platform])
	return ""
}

// listedPersonaID 是 GET /admin/channels 为某个账号报告的 personaId，
// 即面板读回用于渲染角色选择的值。
func listedPersonaID(t *testing.T, ts *httptest.Server, token, platform, accountID string) (string, []byte) {
	t.Helper()
	resp, body := doReq(t, http.MethodGet, ts.URL+"/api/v1/admin/channels", nil, token)
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("get status = %d, want 200 (body=%s)", resp.StatusCode, body)
	}
	var listed []struct {
		Name     string `json:"name"`
		Accounts []struct {
			ID        string `json:"id"`
			PersonaID string `json:"personaId"`
		} `json:"accounts"`
	}
	if err := json.Unmarshal(decodeBody(t, body)["data"], &listed); err != nil {
		t.Fatalf("decode channels list: %v (body=%s)", err, body)
	}
	for _, entry := range listed {
		if entry.Name != platform {
			continue
		}
		for _, acct := range entry.Accounts {
			if acct.ID == accountID {
				return acct.PersonaID, body
			}
		}
	}
	t.Fatalf("account %s/%s not in GET /admin/channels (body=%s)", platform, accountID, body)
	return "", body
}

// TestAdminSaveChannelConfigPersonaIDBindsAndEchoes 绑定一个渠道角色，
// 断言它到达了 channels.json、列表端点回显它供面板渲染，
// 并且热重载路径被执行。
func TestAdminSaveChannelConfigPersonaIDBindsAndEchoes(t *testing.T) {
	t.Parallel()
	path := filepath.Join(t.TempDir(), "channels.json")
	store := &stubChannelConfigStore{path: path, accounts: map[string][]config.ChannelAccount{}}
	_, ts, jwt := buildEnv(t, cfgDefault(), Deps{Channels: store, Personas: personaTestRegistry(t)})
	tok := signAny(t, jwt, "acct", auth.RoleOwner)

	resp, body := doReq(t, http.MethodPut, ts.URL+"/api/v1/admin/channels/telegram/config",
		map[string]any{"id": "conf0", "token": "bot-tok", "personaId": "yuki"}, tok)
	if resp.StatusCode != http.StatusCreated {
		t.Fatalf("save status = %d, want 201 (body=%s)", resp.StatusCode, body)
	}
	if got := storedPersonaID(t, path, "telegram", "conf0"); got != "yuki" {
		t.Fatalf("channels.json telegram.conf0 personaId = %q, want yuki", got)
	}
	if len(store.reloaded) != 1 || store.reloaded[0] != "telegram" {
		t.Fatalf("reloaded = %v, want [telegram] (the panel's hot-reload path)", store.reloaded)
	}

	echoed, listBody := listedPersonaID(t, ts, tok, "telegram", "conf0")
	if echoed != "yuki" {
		t.Fatalf("GET /admin/channels telegram.conf0 personaId = %q, want yuki (body=%s)", echoed, listBody)
	}
	t.Logf("GET /api/v1/admin/channels echoes the binding: %s", listBody)
}

// TestAdminSaveChannelConfigPersonaIDKeptWhenOmitted 是静默数据
// 丢失的回归：除非主人触碰过角色选择，面板会省略 personaId，
// 因此保存另一个字段必须不碰已存绑定。
func TestAdminSaveChannelConfigPersonaIDKeptWhenOmitted(t *testing.T) {
	t.Parallel()
	path := filepath.Join(t.TempDir(), "channels.json")
	store := &stubChannelConfigStore{path: path, accounts: map[string][]config.ChannelAccount{
		"telegram": {{ID: "conf0", Config: map[string]any{"bot_token": "old-tok"}, PersonaID: "yuki"}},
	}}
	_, ts, jwt := buildEnv(t, cfgDefault(), Deps{Channels: store, Personas: personaTestRegistry(t)})
	tok := signAny(t, jwt, "acct", auth.RoleOwner)

	// 线上请求体携带新 token，且完全没有 personaId 键 ——
	// 正是一个未被触碰的角色选择所产生的形态。
	_, body := putChannelConfigRaw(t, ts,
		"telegram", `{"id":"conf0","token":"new-tok","groupMsgPerMin":5}`, tok)

	if got := storedPersonaID(t, path, "telegram", "conf0"); got != "yuki" {
		t.Fatalf("omitted personaId cleared the binding: channels.json personaId = %q, want yuki (resp=%s)", got, body)
	}
	accounts, _ := runtimeconfig.LoadChannels(path, nil)
	if accounts["telegram"][0].Config["bot_token"] != "new-tok" || accounts["telegram"][0].GroupMsgPerMin != 5 {
		t.Fatalf("the other fields were not saved: %+v", accounts["telegram"][0])
	}
	if echoed, listBody := listedPersonaID(t, ts, tok, "telegram", "conf0"); echoed != "yuki" {
		t.Fatalf("GET /admin/channels personaId = %q, want yuki (body=%s)", echoed, listBody)
	}

	// 显式的 JSON null 与键缺失相同：DTO 无法区分二者，
	// 二者都不表示「清除」。
	putChannelConfigRaw(t, ts, "telegram", `{"id":"conf0","token":"newer-tok","personaId":null}`, tok)
	if got := storedPersonaID(t, path, "telegram", "conf0"); got != "yuki" {
		t.Fatalf("null personaId cleared the binding: personaId = %q, want yuki", got)
	}
}

// TestAdminSaveChannelConfigPersonaIDClearedOnExplicitEmpty 断言清除
// 绑定仍然可行，但仅在面板以显式 "" 表示时才如此。
func TestAdminSaveChannelConfigPersonaIDClearedOnExplicitEmpty(t *testing.T) {
	t.Parallel()
	path := filepath.Join(t.TempDir(), "channels.json")
	store := &stubChannelConfigStore{path: path, accounts: map[string][]config.ChannelAccount{
		"telegram": {{ID: "conf0", Config: map[string]any{"bot_token": "old-tok"}, PersonaID: "yuki"}},
	}}
	_, ts, jwt := buildEnv(t, cfgDefault(), Deps{Channels: store, Personas: personaTestRegistry(t)})
	tok := signAny(t, jwt, "acct", auth.RoleOwner)

	putChannelConfigRaw(t, ts, "telegram", `{"id":"conf0","token":"new-tok","personaId":""}`, tok)

	if got := storedPersonaID(t, path, "telegram", "conf0"); got != "" {
		t.Fatalf("explicit \"\" personaId = %q, want the binding cleared", got)
	}
	if echoed, listBody := listedPersonaID(t, ts, tok, "telegram", "conf0"); echoed != "" {
		t.Fatalf("GET /admin/channels personaId = %q, want empty (body=%s)", echoed, listBody)
	}
}

// TestAdminSaveChannelConfigPersonaIDKeptPerAccount 把 read-modify-write
// 钉在正在保存的账号上：某账号省略 personaId 时必须继承该
// 账号自己的绑定，而不是兄弟账号的。
func TestAdminSaveChannelConfigPersonaIDKeptPerAccount(t *testing.T) {
	t.Parallel()
	path := filepath.Join(t.TempDir(), "channels.json")
	store := &stubChannelConfigStore{path: path, accounts: map[string][]config.ChannelAccount{
		"telegram": {
			{ID: "conf0", Config: map[string]any{"bot_token": "a"}, PersonaID: "yuki"},
			{ID: "conf1", Config: map[string]any{"bot_token": "b"}},
		},
	}}
	_, ts, jwt := buildEnv(t, cfgDefault(), Deps{Channels: store, Personas: personaTestRegistry(t)})
	tok := signAny(t, jwt, "acct", auth.RoleOwner)

	putChannelConfigRaw(t, ts, "telegram", `{"id":"conf1","token":"b2"}`, tok)

	if got := storedPersonaID(t, path, "telegram", "conf0"); got != "yuki" {
		t.Fatalf("sibling account conf0 personaId = %q, want yuki untouched", got)
	}
	if got := storedPersonaID(t, path, "telegram", "conf1"); got != "" {
		t.Fatalf("conf1 personaId = %q, want empty (it never had a binding)", got)
	}
}

// TestAdminSaveChannelConfigRejectsUnknownPersonaID 保持保存 fail-closed：
// 绑定到一个库不认识的角色时，渠道会静默地以默认角色应答，
// 因此该绑定被拒绝，不写入也不重载。
func TestAdminSaveChannelConfigRejectsUnknownPersonaID(t *testing.T) {
	t.Parallel()
	path := filepath.Join(t.TempDir(), "channels.json")
	store := &stubChannelConfigStore{path: path, accounts: map[string][]config.ChannelAccount{
		"telegram": {{ID: "conf0", Config: map[string]any{"bot_token": "old-tok"}, PersonaID: "yuki"}},
	}}
	_, ts, jwt := buildEnv(t, cfgDefault(), Deps{Channels: store, Personas: personaTestRegistry(t)})
	tok := signAny(t, jwt, "acct", auth.RoleOwner)

	resp, body := doReq(t, http.MethodPut, ts.URL+"/api/v1/admin/channels/telegram/config",
		map[string]any{"id": "conf0", "token": "bot-tok", "personaId": "nobody"}, tok)
	if resp.StatusCode != http.StatusBadRequest {
		t.Fatalf("unknown personaId status = %d, want 400 (body=%s)", resp.StatusCode, body)
	}
	if !strings.Contains(string(body), "personaId") {
		t.Fatalf("rejection body = %s, want it to name personaId", body)
	}
	if len(store.reloaded) != 0 {
		t.Fatalf("reloaded = %v, want none for a refused save", store.reloaded)
	}
	if _, err := os.Stat(path); !os.IsNotExist(err) {
		t.Fatalf("a refused save must not write channels.json (stat err = %v)", err)
	}
}