package v1

import (
	"encoding/json"
	"mime/multipart"
	"net/http"
	"strconv"
	"strings"

	"github.com/gin-gonic/gin"

	"github.com/gochat/gochat/internal/service"
	applogger "github.com/gochat/gochat/pkg/logger"
	"github.com/gochat/gochat/pkg/response"
)

// ProfileHandler handles Profile get/update + avatar + availability + auto_offline + set_active_account + resend_confirmation + reset_access_token.
// Reference: Chatwoot app/controllers/api/v1/profile_controller.rb
type ProfileHandler struct {
	svc       *service.ProfileService
	uploadSvc *service.UploadService
}

// NewProfileHandler creates a new Profile handler.
func NewProfileHandler(svc *service.ProfileService, uploadSvc ...*service.UploadService) *ProfileHandler {
	handler := &ProfileHandler{svc: svc}
	if len(uploadSvc) > 0 {
		handler.uploadSvc = uploadSvc[0]
	}
	return handler
}

// Get returns the current user's profile.
// GET /api/v1/profile
func (h *ProfileHandler) Get(c *gin.Context) {
	userID := getUserID(c)
	if userID == 0 {
		response.AbortWithStatusError(c, http.StatusUnauthorized, response.ErrUnauthorized, "user not authenticated")
		return
	}

	accountID := c.GetUint("account_id")
	user, err := h.svc.Get(c.Request.Context(), userID, accountID)
	if err != nil {
		applogger.L().Errorf("Get profile for user %d: %v", userID, err)
		handleServiceError(c, err)
		return
	}

	c.JSON(http.StatusOK, user)
}

func (h *ProfileHandler) ListSessions(c *gin.Context) {
	userID := getUserID(c)
	sessions, err := h.svc.ListUserSessions(c.Request.Context(), userID)
	if err != nil {
		handleServiceError(c, err)
		return
	}
	currentClientID := c.GetHeader("client")
	payload := make([]gin.H, 0, len(sessions))
	for i := range sessions {
		session := sessions[i]
		payload = append(payload, gin.H{
			"id": session.ID, "browser_name": session.BrowserName, "browser_version": session.BrowserVersion,
			"device_name": session.DeviceName, "platform_name": session.PlatformName, "platform_version": session.PlatformVersion,
			"ip_address": session.IPAddress, "city": session.City, "country": session.Country, "country_code": session.CountryCode,
			"last_activity_at": session.LastActivityAt, "created_at": session.CreatedAt, "current": session.ClientID == currentClientID,
		})
	}
	c.JSON(http.StatusOK, payload)
}

func (h *ProfileHandler) RevokeSession(c *gin.Context) {
	userID := getUserID(c)
	id, err := strconv.ParseUint(c.Param("id"), 10, 32)
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid session id")
		return
	}
	if err := h.svc.RevokeUserSession(c.Request.Context(), userID, uint(id), c.GetHeader("client")); err != nil {
		if strings.Contains(strings.ToLower(err.Error()), "current session") {
			c.JSON(http.StatusUnprocessableEntity, gin.H{"error": err.Error()})
			return
		}
		handleServiceError(c, err)
		return
	}
	c.Status(http.StatusOK)
}

// Update updates the current user's profile.
// PUT /api/v1/profile
func (h *ProfileHandler) Update(c *gin.Context) {
	userID := getUserID(c)
	if userID == 0 {
		response.AbortWithStatusError(c, http.StatusUnauthorized, response.ErrUnauthorized, "user not authenticated")
		return
	}

	req, avatar, err := bindProfileUpdate(c)
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}

	accountID := c.GetUint("account_id")
	if avatar != nil {
		if h.uploadSvc == nil {
			response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "profile avatar storage is not configured")
			return
		}
		upload, uploadErr := h.uploadSvc.ProfileAvatarUpload(c.Request.Context(), accountID, avatar)
		if uploadErr != nil {
			response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, uploadErr.Error())
			return
		}
		req.Profile.AvatarURL = upload.FileURL
	}
	user, svcErr := h.svc.Update(c.Request.Context(), userID, accountID, req.Profile)
	if svcErr != nil {
		applogger.L().Errorf("Update profile for user %d: %v", userID, svcErr)
		handleServiceError(c, svcErr)
		return
	}

	c.JSON(http.StatusOK, user)
}

func bindProfileUpdate(c *gin.Context) (service.ProfileUpdatePayload, *multipart.FileHeader, error) {
	contentType := c.GetHeader("Content-Type")
	if strings.Contains(contentType, "multipart/form-data") || strings.Contains(contentType, "application/x-www-form-urlencoded") {
		return bindProfileUpdateForm(c)
	}
	var req service.ProfileUpdatePayload
	if err := c.ShouldBindJSON(&req); err != nil {
		return req, nil, err
	}
	return req, nil, nil
}

func bindProfileUpdateForm(c *gin.Context) (service.ProfileUpdatePayload, *multipart.FileHeader, error) {
	var req service.ProfileUpdatePayload
	if err := c.Request.ParseMultipartForm(32 << 20); err != nil && !strings.Contains(err.Error(), "request Content-Type isn't multipart/form-data") {
		return req, nil, err
	}
	form := c.Request.Form
	profile := &req.Profile
	if value := form.Get("profile[name]"); value != "" {
		profile.Name = value
	}
	if value := form.Get("profile[email]"); value != "" {
		profile.Email = value
	}
	if _, ok := form["profile[display_name]"]; ok {
		value := form.Get("profile[display_name]")
		profile.DisplayName = &value
	}
	if _, ok := form["profile[message_signature]"]; ok {
		value := form.Get("profile[message_signature]")
		profile.MessageSignature = &value
	}
	if _, ok := form["profile[phone_number]"]; ok {
		value := form.Get("profile[phone_number]")
		profile.PhoneNumber = &value
	}
	if value := form.Get("profile[avatar_url]"); value != "" {
		profile.AvatarURL = value
	}
	avatar, _ := c.FormFile("profile[avatar]")
	uiSettings := map[string]any{}
	for key, values := range form {
		if !strings.HasPrefix(key, "profile[ui_settings][") || len(values) == 0 {
			continue
		}
		settingKey := strings.TrimSuffix(strings.TrimPrefix(key, "profile[ui_settings]["), "]")
		uiSettings[settingKey] = values[0]
	}
	if raw := form.Get("profile[ui_settings]"); raw != "" {
		var parsed map[string]any
		if err := json.Unmarshal([]byte(raw), &parsed); err == nil {
			uiSettings = parsed
		}
	}
	if len(uiSettings) > 0 {
		profile.UISettings = uiSettings
	}
	return req, avatar, nil
}

// UpdateAvatar updates the current user's avatar.
// PUT /api/v1/profile/avatar
func (h *ProfileHandler) UpdateAvatar(c *gin.Context) {
	userID := getUserID(c)
	if userID == 0 {
		response.AbortWithStatusError(c, http.StatusUnauthorized, response.ErrUnauthorized, "user not authenticated")
		return
	}

	var req service.UpdateAvatarRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}

	accountID := c.GetUint("account_id")
	user, svcErr := h.svc.UpdateAvatar(c.Request.Context(), userID, accountID, req)
	if svcErr != nil {
		applogger.L().Errorf("Update avatar for user %d: %v", userID, svcErr)
		handleServiceError(c, svcErr)
		return
	}

	c.JSON(http.StatusOK, user)
}

// SetAvailability updates the user's availability status for a specific account.
// POST /api/v1/profile/availability
// Reference: Chatwoot profiles_controller#availability
func (h *ProfileHandler) SetAvailability(c *gin.Context) {
	userID := getUserID(c)
	if userID == 0 {
		response.AbortWithStatusError(c, http.StatusUnauthorized, response.ErrUnauthorized, "user not authenticated")
		return
	}

	var req service.ProfileAvailabilityPayload
	if err := c.ShouldBindJSON(&req); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}

	user, svcErr := h.svc.SetAvailability(c.Request.Context(), userID, req.Profile)
	if svcErr != nil {
		applogger.L().Errorf("SetAvailability for user %d: %v", userID, svcErr)
		handleServiceError(c, svcErr)
		return
	}

	c.JSON(http.StatusOK, user)
}

// SetAutoOffline updates the user's auto_offline setting for a specific account.
// POST /api/v1/profile/auto_offline
// Reference: Chatwoot profiles_controller#auto_offline
func (h *ProfileHandler) SetAutoOffline(c *gin.Context) {
	userID := getUserID(c)
	if userID == 0 {
		response.AbortWithStatusError(c, http.StatusUnauthorized, response.ErrUnauthorized, "user not authenticated")
		return
	}

	var req service.ProfileAutoOfflinePayload
	if err := c.ShouldBindJSON(&req); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}

	user, svcErr := h.svc.SetAutoOffline(c.Request.Context(), userID, req.Profile)
	if svcErr != nil {
		applogger.L().Errorf("SetAutoOffline for user %d: %v", userID, svcErr)
		handleServiceError(c, svcErr)
		return
	}

	c.JSON(http.StatusOK, user)
}

// SetActiveAccount sets the user's currently active account.
// PUT /api/v1/profile/set_active_account
// Reference: Chatwoot profiles_controller#set_active_account
func (h *ProfileHandler) SetActiveAccount(c *gin.Context) {
	userID := getUserID(c)
	if userID == 0 {
		response.AbortWithStatusError(c, http.StatusUnauthorized, response.ErrUnauthorized, "user not authenticated")
		return
	}

	var req service.ProfileSetActiveAccountPayload
	if err := c.ShouldBindJSON(&req); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}

	svcErr := h.svc.SetActiveAccount(c.Request.Context(), userID, req.Profile)
	if svcErr != nil {
		applogger.L().Errorf("SetActiveAccount for user %d: %v", userID, svcErr)
		handleServiceError(c, svcErr)
		return
	}

	response.NoContent(c)
}

// ResendConfirmation sends a confirmation email to the user if not yet confirmed.
// POST /api/v1/profile/resend_confirmation
// Reference: Chatwoot auth/resend_confirmations_controller#create
func (h *ProfileHandler) ResendConfirmation(c *gin.Context) {
	userID := getUserID(c)
	if userID == 0 {
		response.AbortWithStatusError(c, http.StatusUnauthorized, response.ErrUnauthorized, "user not authenticated")
		return
	}

	svcErr := h.svc.ResendConfirmation(c.Request.Context(), userID)
	if svcErr != nil {
		applogger.L().Errorf("ResendConfirmation for user %d: %v", userID, svcErr)
		handleServiceError(c, svcErr)
		return
	}

	response.NoContent(c)
}

// ResetAccessToken regenerates the user's access token, invalidating current JWTs.
// POST /api/v1/profile/reset_access_token
// Reference: Chatwoot profiles_controller#reset_access_token
func (h *ProfileHandler) ResetAccessToken(c *gin.Context) {
	userID := getUserID(c)
	if userID == 0 {
		response.AbortWithStatusError(c, http.StatusUnauthorized, response.ErrUnauthorized, "user not authenticated")
		return
	}

	accountID := c.GetUint("account_id")
	user, svcErr := h.svc.ResetAccessToken(c.Request.Context(), userID, accountID)
	if svcErr != nil {
		applogger.L().Errorf("ResetAccessToken for user %d: %v", userID, svcErr)
		handleServiceError(c, svcErr)
		return
	}

	c.JSON(http.StatusOK, user)
}

// DeleteAvatar removes the user's avatar.
// DELETE /api/v1/profile/avatar
// Reference: Chatwoot ProfilesController#destroy_avatar
func (h *ProfileHandler) DeleteAvatar(c *gin.Context) {
	userID := getUserID(c)
	if userID == 0 {
		response.AbortWithStatusError(c, http.StatusUnauthorized, response.ErrUnauthorized, "user not authenticated")
		return
	}
	accountID := c.GetUint("account_id")
	user, err := h.svc.DeleteAvatar(c.Request.Context(), userID, accountID)
	if err != nil {
		applogger.L().Errorf("DeleteAvatar for user %d: %v", userID, err)
		handleServiceError(c, err)
		return
	}
	c.JSON(http.StatusOK, user)
}