package handlers

import (
	"encoding/json"
	"net/http"
	"testing"

	"github.com/gin-gonic/gin"
	"golang.org/x/crypto/bcrypt"

	"chat-switchboard/config"
	"chat-switchboard/database"
	"chat-switchboard/middleware"
	"chat-switchboard/store"
	postgres "chat-switchboard/store/postgres"
	sqlite "chat-switchboard/store/sqlite"
)

// ── Profile Test Harness ──────────────────

type profileHarness struct {
	*testHarness
	userToken string
	userID    string
}

func setupProfileHarness(t *testing.T) *profileHarness {
	t.Helper()
	database.RequireTestDB(t)
	database.TruncateAll(t)

	cfg := &config.Config{
		JWTSecret: testJWTSecret,
		BasePath:  "",
	}

	var stores store.Stores
	if database.IsSQLite() {
		stores = sqlite.NewStores(database.TestDB)
	} else {
		stores = postgres.NewStores(database.TestDB)
	}
	userCache := middleware.NewUserStatusCache()

	r := gin.New()
	api := r.Group("/api/v1")
	protected := api.Group("")
	protected.Use(middleware.Auth(cfg, stores.Users, userCache))

	settings := NewSettingsHandler(stores, nil)
	protected.GET("/profile", settings.GetProfile)
	protected.PUT("/profile", settings.UpdateProfile)
	protected.POST("/profile/password", settings.ChangePassword)
	protected.POST("/profile/avatar", settings.UploadAvatar)
	protected.DELETE("/profile/avatar", settings.DeleteAvatar)
	protected.GET("/settings", settings.GetSettings)
	protected.PUT("/settings", settings.UpdateSettings)

	userID := database.SeedTestUser(t, "profuser", "profuser@test.com")
	database.TestDB.Exec(dialectSQL("UPDATE users SET is_active = true WHERE id = $1"), userID)
	userToken := makeToken(userID, "profuser@test.com", "user")

	return &profileHarness{
		testHarness: &testHarness{router: r, t: t},
		userToken:   userToken,
		userID:      userID,
	}
}

// ── GET /profile ──────────────────────────

func TestProfile_Get_Shape(t *testing.T) {
	h := setupProfileHarness(t)

	resp := h.request("GET", "/api/v1/profile", h.userToken, nil)
	if resp.Code != http.StatusOK {
		t.Fatalf("got %d, body: %s", resp.Code, resp.Body.String())
	}

	var body map[string]interface{}
	json.Unmarshal(resp.Body.Bytes(), &body)

	// Required fields
	for _, key := range []string{"id", "username", "email", "role", "settings", "created_at"} {
		if _, ok := body[key]; !ok {
			t.Errorf("missing required field %q in profile response", key)
		}
	}

	if body["username"] != "profuser" {
		t.Errorf("username: got %v, want profuser", body["username"])
	}
	if body["email"] != "profuser@test.com" {
		t.Errorf("email: got %v, want profuser@test.com", body["email"])
	}
	if body["role"] != "user" {
		t.Errorf("role: got %v, want user", body["role"])
	}

	// settings must be an object (not null)
	settings, ok := body["settings"].(map[string]interface{})
	if !ok {
		t.Errorf("settings should be an object, got %T", body["settings"])
	}
	_ = settings

	// avatar_url should NOT appear (handler uses "avatar" json tag)
	if _, exists := body["avatar_url"]; exists {
		t.Error("profile should return 'avatar' not 'avatar_url'")
	}
}

func TestProfile_Get_RequiresAuth(t *testing.T) {
	h := setupProfileHarness(t)

	resp := h.request("GET", "/api/v1/profile", "", nil)
	if resp.Code != http.StatusUnauthorized {
		t.Fatalf("expected 401 without token, got %d", resp.Code)
	}
}

// ── PUT /profile ──────────────────────────

func TestProfile_Update_DisplayName(t *testing.T) {
	h := setupProfileHarness(t)

	name := "New Name"
	resp := h.request("PUT", "/api/v1/profile", h.userToken, map[string]interface{}{
		"display_name": name,
	})
	if resp.Code != http.StatusOK {
		t.Fatalf("got %d, body: %s", resp.Code, resp.Body.String())
	}

	var body map[string]interface{}
	json.Unmarshal(resp.Body.Bytes(), &body)

	if body["display_name"] != name {
		t.Errorf("display_name: got %v, want %s", body["display_name"], name)
	}
}

func TestProfile_Update_Email(t *testing.T) {
	h := setupProfileHarness(t)

	resp := h.request("PUT", "/api/v1/profile", h.userToken, map[string]interface{}{
		"email": "NEW@TEST.COM",
	})
	if resp.Code != http.StatusOK {
		t.Fatalf("got %d, body: %s", resp.Code, resp.Body.String())
	}

	var body map[string]interface{}
	json.Unmarshal(resp.Body.Bytes(), &body)

	// Email should be lowercased
	if body["email"] != "new@test.com" {
		t.Errorf("email: got %v, want new@test.com", body["email"])
	}
}

func TestProfile_Update_DuplicateEmail_409(t *testing.T) {
	h := setupProfileHarness(t)

	// Seed another user with the target email
	database.SeedTestUser(t, "other", "taken@test.com")

	resp := h.request("PUT", "/api/v1/profile", h.userToken, map[string]interface{}{
		"email": "taken@test.com",
	})
	if resp.Code != http.StatusConflict {
		t.Fatalf("expected 409 for duplicate email, got %d: %s", resp.Code, resp.Body.String())
	}
}

// ── GET /settings ─────────────────────────

func TestSettings_Get_Envelope(t *testing.T) {
	h := setupProfileHarness(t)

	resp := h.request("GET", "/api/v1/settings", h.userToken, nil)
	if resp.Code != http.StatusOK {
		t.Fatalf("got %d, body: %s", resp.Code, resp.Body.String())
	}

	var body map[string]interface{}
	json.Unmarshal(resp.Body.Bytes(), &body)

	// P0: Must have "settings" key — this was the surface test failure
	settings, ok := body["settings"]
	if !ok {
		t.Fatal("GET /settings must return {\"settings\": {...}}, missing \"settings\" key")
	}

	// settings value must be an object (not null)
	settingsMap, ok := settings.(map[string]interface{})
	if !ok {
		t.Fatalf("settings value should be an object, got %T", settings)
	}

	// New user should have empty settings
	if len(settingsMap) != 0 {
		t.Errorf("new user settings should be empty, got %v", settingsMap)
	}
}

// ── PUT /settings ─────────────────────────

func TestSettings_Update_MergeAndEnvelope(t *testing.T) {
	h := setupProfileHarness(t)

	// Set initial
	resp := h.request("PUT", "/api/v1/settings", h.userToken, map[string]interface{}{
		"theme": "dark",
		"lang":  "en",
	})
	if resp.Code != http.StatusOK {
		t.Fatalf("initial PUT: got %d, body: %s", resp.Code, resp.Body.String())
	}

	var body1 map[string]interface{}
	json.Unmarshal(resp.Body.Bytes(), &body1)
	settings1, _ := body1["settings"].(map[string]interface{})
	if settings1["theme"] != "dark" || settings1["lang"] != "en" {
		t.Fatalf("initial settings: got %v", settings1)
	}

	// Merge: change theme, keep lang
	resp2 := h.request("PUT", "/api/v1/settings", h.userToken, map[string]interface{}{
		"theme": "light",
	})
	if resp2.Code != http.StatusOK {
		t.Fatalf("merge PUT: got %d, body: %s", resp2.Code, resp2.Body.String())
	}

	var body2 map[string]interface{}
	json.Unmarshal(resp2.Body.Bytes(), &body2)
	settings2, _ := body2["settings"].(map[string]interface{})

	if settings2["theme"] != "light" {
		t.Errorf("theme should be overwritten to 'light', got %v", settings2["theme"])
	}
	if settings2["lang"] != "en" {
		t.Errorf("lang should be preserved as 'en', got %v", settings2["lang"])
	}

	// Verify via GET
	resp3 := h.request("GET", "/api/v1/settings", h.userToken, nil)
	var body3 map[string]interface{}
	json.Unmarshal(resp3.Body.Bytes(), &body3)
	settings3, _ := body3["settings"].(map[string]interface{})
	if settings3["theme"] != "light" || settings3["lang"] != "en" {
		t.Errorf("GET after merge: got %v", settings3)
	}
}

// ── POST /profile/password ────────────────

func TestProfile_ChangePassword(t *testing.T) {
	h := setupProfileHarness(t)

	// Seed user with a known bcrypt hash for "oldpassword"
	// The default SeedTestUser uses a dummy hash. We need a real one.
	hash, _ := hashPassword("oldpassword")
	database.TestDB.Exec(dialectSQL("UPDATE users SET password_hash = $1 WHERE id = $2"), hash, h.userID)

	// Change password
	resp := h.request("POST", "/api/v1/profile/password", h.userToken, map[string]interface{}{
		"current_password": "oldpassword",
		"new_password":     "newpassword123",
	})
	if resp.Code != http.StatusOK {
		t.Fatalf("got %d, body: %s", resp.Code, resp.Body.String())
	}

	var body map[string]interface{}
	json.Unmarshal(resp.Body.Bytes(), &body)
	if body["message"] != "password updated" {
		t.Errorf("expected success message, got %v", body)
	}
}

func TestProfile_ChangePassword_WrongCurrent_401(t *testing.T) {
	h := setupProfileHarness(t)

	hash, _ := hashPassword("correctpassword")
	database.TestDB.Exec(dialectSQL("UPDATE users SET password_hash = $1 WHERE id = $2"), hash, h.userID)

	resp := h.request("POST", "/api/v1/profile/password", h.userToken, map[string]interface{}{
		"current_password": "wrongpassword",
		"new_password":     "newpassword123",
	})
	if resp.Code != http.StatusUnauthorized {
		t.Fatalf("expected 401 for wrong current password, got %d: %s", resp.Code, resp.Body.String())
	}
}

func TestProfile_ChangePassword_TooShort_400(t *testing.T) {
	h := setupProfileHarness(t)

	hash, _ := hashPassword("oldpassword")
	database.TestDB.Exec(dialectSQL("UPDATE users SET password_hash = $1 WHERE id = $2"), hash, h.userID)

	resp := h.request("POST", "/api/v1/profile/password", h.userToken, map[string]interface{}{
		"current_password": "oldpassword",
		"new_password":     "short",
	})
	if resp.Code != http.StatusBadRequest {
		t.Fatalf("expected 400 for short password, got %d: %s", resp.Code, resp.Body.String())
	}
}

// ── DELETE /profile/avatar ────────────────

func TestProfile_DeleteAvatar(t *testing.T) {
	h := setupProfileHarness(t)

	// Set an avatar first
	database.TestDB.Exec(dialectSQL("UPDATE users SET avatar_url = $1 WHERE id = $2"),
		"data:image/png;base64,test", h.userID)

	resp := h.request("DELETE", "/api/v1/profile/avatar", h.userToken, nil)
	if resp.Code != http.StatusOK {
		t.Fatalf("got %d, body: %s", resp.Code, resp.Body.String())
	}

	// Verify avatar is cleared in profile
	resp2 := h.request("GET", "/api/v1/profile", h.userToken, nil)
	var body map[string]interface{}
	json.Unmarshal(resp2.Body.Bytes(), &body)

	// avatar should be omitted (omitempty) or null
	if av, exists := body["avatar"]; exists && av != nil {
		t.Errorf("avatar should be cleared, got %v", av)
	}
}

// ── Helper ────────────────────────────────

func hashPassword(pw string) (string, error) {
	h, err := bcrypt.GenerateFromPassword([]byte(pw), bcryptCost)
	return string(h), err
}