package httpapi

import (
	"context"
	"database/sql"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
	"time"

	"github.com/wangjia/pangolin/server/internal/codes"
	"github.com/wangjia/pangolin/server/internal/config"
	"github.com/wangjia/pangolin/server/internal/routing"
	"github.com/wangjia/pangolin/server/internal/store"
)

// openRoutingTestDB opens an in-memory SQLite DB with migrations applied,
// mirroring internal/routing/store_sqlite_test.go's helper (no shared helper
// exists in this package yet).
func openRoutingTestDB(t *testing.T) *sql.DB {
	t.Helper()
	db, err := store.Open(&config.Config{Driver: "sqlite", DSN: ":memory:"})
	if err != nil {
		t.Fatal(err)
	}
	t.Cleanup(func() { _ = db.Close() })
	if err := store.MigrateUp(db, "sqlite"); err != nil {
		t.Fatal(err)
	}
	if err := store.ApplyCodesLibMigrations(context.Background(), db, "sqlite"); err != nil {
		t.Fatal(err)
	}
	return db
}

func seedRoutingUser(t *testing.T, db *sql.DB, id int64) {
	t.Helper()
	uuid := "u-routing"
	if _, err := db.Exec(`INSERT INTO users (id,uuid,email,pw_hash,dp_uuid,status,created_at)
		VALUES (?,?,?, 'x','dp-'||?, 'active', ?)`, id, uuid, uuid+"@x", uuid, time.Now().UTC()); err != nil {
		t.Fatal(err)
	}
}

// doAuthReq builds an httptest request with an authenticated context (numeric
// user id injected under codes.CtxKeyUserID, matching auth.RequireAuth) and
// invokes the handler directly (no router needed for a single route).
func doAuthReq(t *testing.T, method, target string, body *strings.Reader, uid int64, h http.HandlerFunc) *httptest.ResponseRecorder {
	t.Helper()
	var req *http.Request
	if body == nil {
		req = httptest.NewRequest(method, target, nil)
	} else {
		req = httptest.NewRequest(method, target, body)
	}
	ctx := context.WithValue(req.Context(), codes.CtxKeyUserID, uid)
	req = req.WithContext(ctx)
	rr := httptest.NewRecorder()
	h(rr, req)
	return rr
}

func TestRoutingGetDefaultThenSave(t *testing.T) {
	db := openRoutingTestDB(t)
	seedRoutingUser(t, db, 7)
	api := NewRoutingAPI(routing.NewStore(db), nil)

	// GET 无档案 → 200 + Default
	rr := doAuthReq(t, http.MethodGet, "/v1/me/routing", nil, 7, api.GetProfile)
	if rr.Code != 200 {
		t.Fatalf("GET code %d", rr.Code)
	}
	var p routing.Profile
	if err := json.Unmarshal(rr.Body.Bytes(), &p); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}
	if p.Mode != "rule" {
		t.Fatalf("default mode %s", p.Mode)
	}

	// POST 合法 → 200
	body := `{"mode":"rule","builtin":{"china_direct":true,"lan_direct":true,"private_via_tunnel":true},"rules":[{"type":"domain_suffix","value":"x.com","action":"direct","enabled":true}],"final":"proxy"}`
	rr = doAuthReq(t, http.MethodPost, "/v1/me/routing", strings.NewReader(body), 7, api.SaveProfile)
	if rr.Code != 200 {
		t.Fatalf("POST code %d body %s", rr.Code, rr.Body)
	}

	// GET 后应能取回刚保存的档案
	rr = doAuthReq(t, http.MethodGet, "/v1/me/routing", nil, 7, api.GetProfile)
	if rr.Code != 200 {
		t.Fatalf("GET-after-save code %d", rr.Code)
	}
	var p2 routing.Profile
	if err := json.Unmarshal(rr.Body.Bytes(), &p2); err != nil {
		t.Fatalf("unmarshal2: %v", err)
	}
	if len(p2.Rules) != 1 || p2.Rules[0].Value != "x.com" {
		t.Fatalf("saved profile not persisted: %+v", p2)
	}

	// POST 非法 → 400 + errors
	rr = doAuthReq(t, http.MethodPost, "/v1/me/routing", strings.NewReader(`{"mode":"x","final":"y","rules":[]}`), 7, api.SaveProfile)
	if rr.Code != 400 {
		t.Fatalf("bad POST code %d", rr.Code)
	}
	var errBody map[string]any
	if err := json.Unmarshal(rr.Body.Bytes(), &errBody); err != nil {
		t.Fatalf("unmarshal err body: %v", err)
	}
	if errBody["code"] != "routing_invalid" {
		t.Fatalf("bad POST body code = %v", errBody["code"])
	}
	errs, ok := errBody["errors"].([]any)
	if !ok || len(errs) == 0 {
		t.Fatalf("expected non-empty errors, got %v", errBody["errors"])
	}
}

func TestRoutingGetUnauthorized(t *testing.T) {
	db := openRoutingTestDB(t)
	api := NewRoutingAPI(routing.NewStore(db), nil)
	req := httptest.NewRequest(http.MethodGet, "/v1/me/routing", nil)
	rr := httptest.NewRecorder()
	api.GetProfile(rr, req)
	if rr.Code != http.StatusUnauthorized {
		t.Fatalf("expected 401, got %d", rr.Code)
	}
}

// TestRoutingGetExposesSystemLockedDomains: GET must surface the injected
// lockedDomains list under system_locked_domains, without it ever ending up
// as part of routing.Profile's own field set.
func TestRoutingGetExposesSystemLockedDomains(t *testing.T) {
	db := openRoutingTestDB(t)
	seedRoutingUser(t, db, 8)
	api := NewRoutingAPI(routing.NewStore(db), []string{"nas.x.com"})

	rr := doAuthReq(t, http.MethodGet, "/v1/me/routing", nil, 8, api.GetProfile)
	if rr.Code != 200 {
		t.Fatalf("GET code %d", rr.Code)
	}
	var resp struct {
		SystemLockedDomains []string `json:"system_locked_domains"`
	}
	if err := json.Unmarshal(rr.Body.Bytes(), &resp); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}
	if len(resp.SystemLockedDomains) != 1 || resp.SystemLockedDomains[0] != "nas.x.com" {
		t.Fatalf("want system_locked_domains=[nas.x.com], got %v", resp.SystemLockedDomains)
	}
}

// TestRoutingGetSystemLockedDomainsNilBecomesEmptyArray: a nil lockedDomains
// slice (no PANGOLIN_PRIVATE_SPLIT_DOMAINS configured) must serialize as
// `[]`, not `null` — clients shouldn't need a nil-check.
func TestRoutingGetSystemLockedDomainsNilBecomesEmptyArray(t *testing.T) {
	db := openRoutingTestDB(t)
	seedRoutingUser(t, db, 9)
	api := NewRoutingAPI(routing.NewStore(db), nil)

	rr := doAuthReq(t, http.MethodGet, "/v1/me/routing", nil, 9, api.GetProfile)
	if rr.Code != 200 {
		t.Fatalf("GET code %d", rr.Code)
	}
	var raw map[string]json.RawMessage
	if err := json.Unmarshal(rr.Body.Bytes(), &raw); err != nil {
		t.Fatalf("unmarshal: %v", err)
	}
	if got := string(raw["system_locked_domains"]); got != "[]" {
		t.Fatalf("want system_locked_domains=`[]`, got %s", got)
	}
}

// TestRoutingSaveIgnoresSystemLockedDomains: a client POSTing a body that
// includes system_locked_domains must not have it persisted — SaveProfile
// decodes straight into routing.Profile, which has no such field, so the
// key is silently dropped. Verify against the raw stored row (not the GET
// response, which always injects it from a.lockedDomains regardless of what
// was ever saved).
func TestRoutingSaveIgnoresSystemLockedDomains(t *testing.T) {
	db := openRoutingTestDB(t)
	seedRoutingUser(t, db, 10)
	store := routing.NewStore(db)
	api := NewRoutingAPI(store, []string{"nas.x.com"})

	body := `{"mode":"rule","builtin":{"china_direct":true,"lan_direct":true,"private_via_tunnel":true},` +
		`"rules":[],"final":"proxy","system_locked_domains":["evil.attacker.com"]}`
	rr := doAuthReq(t, http.MethodPost, "/v1/me/routing", strings.NewReader(body), 10, api.SaveProfile)
	if rr.Code != 200 {
		t.Fatalf("POST code %d body %s", rr.Code, rr.Body)
	}

	stored, err := store.Get(context.Background(), 10)
	if err != nil {
		t.Fatal(err)
	}
	if stored == nil {
		t.Fatal("expected a persisted profile")
	}
	raw, err := json.Marshal(stored)
	if err != nil {
		t.Fatal(err)
	}
	if strings.Contains(string(raw), "system_locked_domains") || strings.Contains(string(raw), "evil.attacker.com") {
		t.Fatalf("system_locked_domains must never be persisted, got stored profile JSON: %s", raw)
	}
}