package service

import (
	"context"
	"crypto/rand"
	"encoding/hex"
	"encoding/json"
	"errors"
	"fmt"

	"github.com/gochat/gochat/internal/campaign"
	whatsapp "github.com/gochat/gochat/internal/channel/whatsapp"
	"github.com/gochat/gochat/internal/model"
	channelmodel "github.com/gochat/gochat/internal/model/channel"
	"github.com/gochat/gochat/internal/repository"
	applogger "github.com/gochat/gochat/pkg/logger"
	pkgvalidator "github.com/gochat/gochat/pkg/validator"
)

// InboxService implements business logic for Inbox operations.
// Reference: Chatwoot app/controllers/api/v1/inboxes_controller.rb
type InboxService struct {
	repo              *repository.InboxRepo
	agentBotInboxRepo *repository.AgentBotInboxRepo
	agentBotRepo      *repository.AgentBotRepo
	campaignRepo      *repository.CampaignRepo
	webhookSubRepo    *repository.WebhookSubscriptionRepo
	whatsappService   *whatsapp.WhatsAppService
	whatsappRepo      *whatsapp.Repository
}

// NewInboxService creates a new Inbox service.
func NewInboxService(
	repo *repository.InboxRepo,
	agentBotInboxRepo *repository.AgentBotInboxRepo,
	agentBotRepo *repository.AgentBotRepo,
	campaignRepo *repository.CampaignRepo,
	webhookSubRepo *repository.WebhookSubscriptionRepo,
	whatsappService *whatsapp.WhatsAppService,
	whatsappRepo *whatsapp.Repository,
) *InboxService {
	return &InboxService{
		repo:              repo,
		agentBotInboxRepo: agentBotInboxRepo,
		agentBotRepo:      agentBotRepo,
		campaignRepo:      campaignRepo,
		webhookSubRepo:    webhookSubRepo,
		whatsappService:   whatsappService,
		whatsappRepo:      whatsappRepo,
	}
}

// Ready reports whether the service has its primary repository configured.
func (s *InboxService) Ready() bool {
	return s != nil && s.repo != nil
}

// ListByAccount retrieves all inboxes for an account.
func (s *InboxService) ListByAccount(ctx context.Context, accountID uint, offset, limit int) ([]model.Inbox, int64, error) {
	return s.repo.FindByAccount(ctx, accountID, offset, limit)
}

// GetByID retrieves a single inbox.
func (s *InboxService) GetByID(ctx context.Context, id uint) (*model.Inbox, error) {
	return s.repo.FindByID(ctx, id)
}

// GetByAccountAndID retrieves an inbox scoped to an account.
func (s *InboxService) GetByAccountAndID(ctx context.Context, accountID, id uint) (*model.Inbox, error) {
	return s.repo.FindByAccountAndID(ctx, accountID, id)
}

// CreateInboxRequest is the DTO for creating an inbox.
type CreateInboxRequest struct {
	Name                 string `json:"name" validate:"required,min=2"`
	ChannelType          string `json:"channel_type" validate:"required,oneof=web_widget telegram facebook instagram whatsapp email api tiktok line twilio_sms"`
	Enabled              bool   `json:"enabled"`
	EnableAutoAssignment bool   `json:"enable_auto_assignment"`
}

// Create creates a new inbox.
func (s *InboxService) Create(ctx context.Context, accountID uint, req CreateInboxRequest) (*model.Inbox, error) {
	if err := pkgvalidator.ValidateStruct(req); err != nil {
		return nil, err
	}

	validChannelTypes := map[string]bool{
		"web_widget": true, "telegram": true, "facebook": true,
		"instagram": true, "whatsapp": true, "email": true, "api": true,
		"tiktok": true, "line": true, "twilio_sms": true,
	}
	if !validChannelTypes[req.ChannelType] {
		return nil, errors.New("invalid channel_type")
	}

	inbox := &model.Inbox{
		AccountID:            accountID,
		Name:                 req.Name,
		ChannelType:          req.ChannelType,
		Enabled:              req.Enabled,
		EnableAutoAssignment: req.EnableAutoAssignment,
	}

	// ChannelID is set after channel-specific config is created
	// For now, default to 0; channel provider will update this
	inbox.ChannelID = 0

	if err := s.repo.Create(ctx, inbox); err != nil {
		applogger.L().Errorf("Failed to create inbox: %v", err)
		return nil, err
	}
	return inbox, nil
}

// UpdateInboxRequest is the DTO for updating an inbox.
type UpdateInboxRequest struct {
	Name                 string `json:"name,omitempty" validate:"omitempty,min=2"`
	Enabled              *bool  `json:"enabled,omitempty"`
	EnableAutoAssignment *bool  `json:"enable_auto_assignment,omitempty"`
}

// Update modifies an existing inbox.
func (s *InboxService) Update(ctx context.Context, accountID, id uint, req UpdateInboxRequest) (*model.Inbox, error) {
	if err := pkgvalidator.ValidateStruct(req); err != nil {
		return nil, err
	}

	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, id)
	if err != nil {
		return nil, err
	}

	if req.Name != "" {
		inbox.Name = req.Name
	}
	if req.Enabled != nil {
		inbox.Enabled = *req.Enabled
	}
	if req.EnableAutoAssignment != nil {
		inbox.EnableAutoAssignment = *req.EnableAutoAssignment
	}

	if err := s.repo.Update(ctx, inbox); err != nil {
		return nil, err
	}
	return inbox, nil
}

// Delete soft-deletes an inbox.
func (s *InboxService) Delete(ctx context.Context, id uint) error {
	return s.repo.Delete(ctx, id)
}

// DeleteByAccount soft-deletes an inbox scoped to an account.
func (s *InboxService) DeleteByAccount(ctx context.Context, accountID, id uint) error {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, id)
	if err != nil {
		return err
	}
	return s.repo.Delete(ctx, inbox.ID)
}

// --- WebWidget-specific methods ---
// Reference: Chatwoot app/models/channel/web_widget.rb + web_widget_config_controller.rb

// WebWidgetConfig represents the channel_config JSON structure for a web_widget inbox.
// Reference: Chatwoot app/models/channel/web_widget.rb — stores widget_token, hmac_token,
// widget_color, welcome_title, welcome_tagline, greeting_enabled, etc.
type WebWidgetConfig struct {
	WebsiteToken          string `json:"website_token"`
	HMACToken             string `json:"hmac_token"`
	WidgetColor           string `json:"widget_color,omitempty"`
	WelcomeTitle          string `json:"welcome_title,omitempty"`
	WelcomeTagline        string `json:"welcome_tagline,omitempty"`
	GreetingEnabled       bool   `json:"greeting_enabled,omitempty"`
	GreetingMessage       string `json:"greeting_message,omitempty"`
	ReplyTime             string `json:"reply_time,omitempty"` // "a_few_minutes", "a_few_hours", "in_a_day"
	PreChatMessage        string `json:"pre_chat_message,omitempty"`
	PreChatFieldsEnabled  bool   `json:"pre_chat_fields_enabled,omitempty"`
	AutoAssignmentEnabled bool   `json:"auto_assignment_enabled,omitempty"`
	ContinuityViaEmail    bool   `json:"continuity_via_email,omitempty"`
	OfflineMessageEnabled bool   `json:"offline_message_enabled,omitempty"`     // M11: Allow offline messages
	OfflineMessageTitle   string `json:"offline_message_title,omitempty"`       // M11: Offline form title
	OfflineMessageDesc    string `json:"offline_message_description,omitempty"` // M11: Offline form description
}

// CreateWebWidgetInboxRequest is the DTO for creating a web_widget inbox.
// Reference: Chatwoot inboxes#create with channel_type=web_widget
type CreateWebWidgetInboxRequest struct {
	Name                  string `json:"name" validate:"required,min=2"`
	WidgetColor           string `json:"widget_color,omitempty"`
	WelcomeTitle          string `json:"welcome_title,omitempty"`
	WelcomeTagline        string `json:"welcome_tagline,omitempty"`
	GreetingEnabled       bool   `json:"greeting_enabled,omitempty"`
	GreetingMessage       string `json:"greeting_message,omitempty"`
	ReplyTime             string `json:"reply_time,omitempty"`
	PreChatMessage        string `json:"pre_chat_message,omitempty"`
	PreChatFieldsEnabled  bool   `json:"pre_chat_fields_enabled,omitempty"`
	AutoAssignmentEnabled bool   `json:"auto_assignment_enabled,omitempty"`
	ContinuityViaEmail    bool   `json:"continuity_via_email,omitempty"`
	EnableAutoAssignment  bool   `json:"enable_auto_assignment,omitempty"`
}

// UpdateWebWidgetConfigRequest is the DTO for updating widget config.
// Reference: Chatwoot web_widget_config#update — only widget-specific fields
type UpdateWebWidgetConfigRequest struct {
	WidgetColor           *string `json:"widget_color,omitempty"`
	WelcomeTitle          *string `json:"welcome_title,omitempty"`
	WelcomeTagline        *string `json:"welcome_tagline,omitempty"`
	GreetingEnabled       *bool   `json:"greeting_enabled,omitempty"`
	GreetingMessage       *string `json:"greeting_message,omitempty"`
	ReplyTime             *string `json:"reply_time,omitempty"`
	PreChatMessage        *string `json:"pre_chat_message,omitempty"`
	PreChatFieldsEnabled  *bool   `json:"pre_chat_fields_enabled,omitempty"`
	AutoAssignmentEnabled *bool   `json:"auto_assignment_enabled,omitempty"`
	ContinuityViaEmail    *bool   `json:"continuity_via_email,omitempty"`
}

// CreateWebWidgetInbox creates a new inbox with channel_type=web_widget
// and auto-generates website_token and hmac_token.
// Reference: Chatwoot Inbox#create_web_widget — generates tokens on creation
func (s *InboxService) CreateWebWidgetInbox(ctx context.Context, accountID uint, req CreateWebWidgetInboxRequest) (*model.Inbox, error) {
	if err := pkgvalidator.ValidateStruct(req); err != nil {
		return nil, err
	}

	// Generate website_token and hmac_token (ref: Chatwoot's SecureRandom.hex)
	websiteToken, err := widgetGenerateToken(12)
	if err != nil {
		applogger.L().Errorf("Failed to generate website_token: %v", err)
		return nil, err
	}
	hmacToken, err := widgetGenerateToken(24)
	if err != nil {
		applogger.L().Errorf("Failed to generate hmac_token: %v", err)
		return nil, err
	}

	// Build the widget config
	widgetConfig := WebWidgetConfig{
		WebsiteToken:          websiteToken,
		HMACToken:             hmacToken,
		WidgetColor:           req.WidgetColor,
		WelcomeTitle:          req.WelcomeTitle,
		WelcomeTagline:        req.WelcomeTagline,
		GreetingEnabled:       req.GreetingEnabled,
		GreetingMessage:       req.GreetingMessage,
		ReplyTime:             req.ReplyTime,
		PreChatMessage:        req.PreChatMessage,
		PreChatFieldsEnabled:  req.PreChatFieldsEnabled,
		AutoAssignmentEnabled: req.AutoAssignmentEnabled,
		ContinuityViaEmail:    req.ContinuityViaEmail,
	}

	configJSON, err := json.Marshal(widgetConfig)
	if err != nil {
		applogger.L().Errorf("Failed to marshal widget config: %v", err)
		return nil, err
	}

	inbox := &model.Inbox{
		AccountID:            accountID,
		Name:                 req.Name,
		ChannelType:          "web_widget",
		Enabled:              true,
		EnableAutoAssignment: req.EnableAutoAssignment,
		ChannelConfig:        string(configJSON),
	}

	if err := s.repo.Create(ctx, inbox); err != nil {
		applogger.L().Errorf("Failed to create web_widget inbox: %v", err)
		return nil, err
	}
	return inbox, nil
}

// GetWebWidgetConfig retrieves and parses the web_widget channel_config for an inbox.
// Reference: Chatwoot web_widget_config#show
func (s *InboxService) GetWebWidgetConfig(ctx context.Context, accountID, inboxID uint) (*WebWidgetConfig, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, err
	}

	if inbox.ChannelType != "web_widget" {
		return nil, errors.New("inbox is not a web_widget channel")
	}

	var config WebWidgetConfig
	if inbox.ChannelConfig != "" {
		if err := json.Unmarshal([]byte(inbox.ChannelConfig), &config); err != nil {
			applogger.L().Errorf("Failed to unmarshal widget config: %v", err)
			return nil, err
		}
	}
	return &config, nil
}

// UpdateWebWidgetConfig updates the widget-specific fields in channel_config.
// Reference: Chatwoot web_widget_config#update — merge update into existing config
func (s *InboxService) UpdateWebWidgetConfig(ctx context.Context, accountID, inboxID uint, req UpdateWebWidgetConfigRequest) (*model.Inbox, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, err
	}

	if inbox.ChannelType != "web_widget" {
		return nil, errors.New("inbox is not a web_widget channel")
	}

	// Parse existing config
	var config WebWidgetConfig
	if inbox.ChannelConfig != "" {
		if err := json.Unmarshal([]byte(inbox.ChannelConfig), &config); err != nil {
			applogger.L().Errorf("Failed to unmarshal existing widget config: %v", err)
			return nil, err
		}
	}

	// Merge partial updates
	if req.WidgetColor != nil {
		config.WidgetColor = *req.WidgetColor
	}
	if req.WelcomeTitle != nil {
		config.WelcomeTitle = *req.WelcomeTitle
	}
	if req.WelcomeTagline != nil {
		config.WelcomeTagline = *req.WelcomeTagline
	}
	if req.GreetingEnabled != nil {
		config.GreetingEnabled = *req.GreetingEnabled
	}
	if req.GreetingMessage != nil {
		config.GreetingMessage = *req.GreetingMessage
	}
	if req.ReplyTime != nil {
		config.ReplyTime = *req.ReplyTime
	}
	if req.PreChatMessage != nil {
		config.PreChatMessage = *req.PreChatMessage
	}
	if req.PreChatFieldsEnabled != nil {
		config.PreChatFieldsEnabled = *req.PreChatFieldsEnabled
	}
	if req.AutoAssignmentEnabled != nil {
		config.AutoAssignmentEnabled = *req.AutoAssignmentEnabled
	}
	if req.ContinuityViaEmail != nil {
		config.ContinuityViaEmail = *req.ContinuityViaEmail
	}

	// Re-serialize config
	configJSON, err := json.Marshal(config)
	if err != nil {
		applogger.L().Errorf("Failed to marshal updated widget config: %v", err)
		return nil, err
	}
	inbox.ChannelConfig = string(configJSON)

	if err := s.repo.Update(ctx, inbox); err != nil {
		return nil, err
	}
	return inbox, nil
}

// widgetGenerateToken creates a random hex token of the specified byte length.
// Reference: Chatwoot uses SecureRandom.hex for token generation
func widgetGenerateToken(byteLen int) (string, error) {
	b := make([]byte, byteLen)
	if _, err := rand.Read(b); err != nil {
		return "", err
	}
	return hex.EncodeToString(b), nil
}

// --- Telegram-specific methods ---
// Reference: Chatwoot app/controllers/api/v1/accounts/channels/telegram_bots_controller.rb
// Reference: Chatwoot app/models/channel/telegram.rb

// TelegramInboxConfig represents the channel_config JSON structure for a telegram inbox.
// Reference: Chatwoot stores bot_token and bot_name in ChannelTelegram model.
// In gochat, we store them both in ChannelTelegram model AND in channel_config
// for quick Inbox-level access.
type TelegramInboxConfig struct {
	BotToken       string `json:"bot_token"`
	BotName        string `json:"bot_name"`
	WelcomeMessage string `json:"welcome_message,omitempty"`
	WebhookURL     string `json:"webhook_url,omitempty"`
}

// CreateTelegramInboxRequest is the DTO for creating a telegram inbox.
// Reference: Chatwoot TelegramBotsController#create
type CreateTelegramInboxRequest struct {
	Name                 string `json:"name" validate:"required,min=2"`
	BotToken             string `json:"bot_token" validate:"required"`
	WelcomeMessage       string `json:"welcome_message,omitempty"`
	EnableAutoAssignment bool   `json:"enable_auto_assignment,omitempty"`
}

// UpdateTelegramInboxRequest is the DTO for updating a telegram inbox.
// Reference: Chatwoot TelegramBotsController#update — only bot_token is editable
type UpdateTelegramInboxRequest struct {
	BotToken       *string `json:"bot_token,omitempty"`
	WelcomeMessage *string `json:"welcome_message,omitempty"`
	Name           *string `json:"name,omitempty"`
	Enabled        *bool   `json:"enabled,omitempty"`
}

// CreateTelegramInbox creates a new Telegram channel inbox.
// Reference: Chatwoot TelegramBotsController#create
// Flow: validate bot_token via getMe → create ChannelTelegram → setup webhook → create Inbox
//
// The TelegramService handles bot token validation and webhook setup.
// The InboxService handles the Inbox creation and links it to the ChannelTelegram.
func (s *InboxService) CreateTelegramInbox(ctx context.Context, accountID uint, req CreateTelegramInboxRequest) (*model.Inbox, error) {
	if err := pkgvalidator.ValidateStruct(req); err != nil {
		return nil, err
	}

	// Note: bot token validation and webhook setup are handled by TelegramService
	// at the handler/service layer. The InboxService focuses on Inbox persistence.
	// The handler calls TelegramService.CreateChannel first, then creates the Inbox.

	// Build the Telegram config
	telConfig := TelegramInboxConfig{
		BotToken:       req.BotToken,
		WelcomeMessage: req.WelcomeMessage,
	}

	configJSON, err := json.Marshal(telConfig)
	if err != nil {
		applogger.L().Errorf("Failed to marshal telegram config: %v", err)
		return nil, err
	}

	inbox := &model.Inbox{
		AccountID:            accountID,
		Name:                 req.Name,
		ChannelType:          "telegram",
		Enabled:              true,
		EnableAutoAssignment: req.EnableAutoAssignment,
		ChannelConfig:        string(configJSON),
	}

	if err := s.repo.Create(ctx, inbox); err != nil {
		applogger.L().Errorf("Failed to create telegram inbox: %v", err)
		return nil, err
	}

	applogger.L().Infof("Telegram inbox created (account_id=%d, inbox_id=%d)", accountID, inbox.ID)
	return inbox, nil
}

// UpdateTelegramInbox updates a Telegram channel inbox.
// Reference: Chatwoot TelegramBotsController#update
// Only bot_token is editable. Updating bot_token triggers re-validation + re-webhook setup.
func (s *InboxService) UpdateTelegramInbox(ctx context.Context, accountID, inboxID uint, req UpdateTelegramInboxRequest) (*model.Inbox, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("telegram inbox not found: %w", err)
	}

	if inbox.ChannelType != "telegram" {
		return nil, fmt.Errorf("inbox is not a telegram channel (channel_type=%s)", inbox.ChannelType)
	}

	// Parse existing config
	var config TelegramInboxConfig
	if inbox.ChannelConfig != "" {
		if err := json.Unmarshal([]byte(inbox.ChannelConfig), &config); err != nil {
			applogger.L().Errorf("Failed to unmarshal existing telegram config: %v", err)
			return nil, fmt.Errorf("failed to parse telegram config: %w", err)
		}
	}

	// Apply updates
	if req.BotToken != nil {
		config.BotToken = *req.BotToken
		// Note: Bot token re-validation and webhook re-setup are handled by TelegramService
		// at the handler/service layer, not here.
	}
	if req.WelcomeMessage != nil {
		config.WelcomeMessage = *req.WelcomeMessage
	}
	if req.Name != nil {
		inbox.Name = *req.Name
	}
	if req.Enabled != nil {
		inbox.Enabled = *req.Enabled
	}

	// Re-serialize config
	configJSON, err := json.Marshal(config)
	if err != nil {
		applogger.L().Errorf("Failed to marshal updated telegram config: %v", err)
		return nil, err
	}
	inbox.ChannelConfig = string(configJSON)

	if err := s.repo.Update(ctx, inbox); err != nil {
		return nil, err
	}
	return inbox, nil
}

// DeleteTelegramInbox deletes a Telegram channel inbox.
// Reference: Chatwoot TelegramBotsController#destroy
// Flow: delete webhook from Telegram → delete ChannelTelegram → delete Inbox
//
// Note: Webhook deletion is handled by TelegramService at the handler/service layer
// BEFORE calling this method. Go doesn't have after_destroy callbacks like Chatwoot.
func (s *InboxService) DeleteTelegramInbox(ctx context.Context, accountID, inboxID uint) error {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return fmt.Errorf("telegram inbox not found: %w", err)
	}

	if inbox.ChannelType != "telegram" {
		return fmt.Errorf("inbox is not a telegram channel (channel_type=%s)", inbox.ChannelType)
	}

	// Note: Telegram webhook deletion should be done BEFORE this call
	// (by the handler calling TelegramService.DeleteChannel)
	// and ChannelTelegram record deletion should also happen before this call.

	if err := s.repo.Delete(ctx, inbox.ID); err != nil {
		applogger.L().Errorf("Failed to delete telegram inbox: %v", err)
		return err
	}

	applogger.L().Infof("Telegram inbox deleted (account_id=%d, inbox_id=%d)", accountID, inboxID)
	return nil
}

// ReauthorizeTelegramInbox re-validates the bot token and re-sets the webhook.
// Reference: Chatwoot sets reauthorization_required=true when webhook/bot fails.
// This method re-validates the bot token via getMe API and re-sets the webhook.
func (s *InboxService) ReauthorizeTelegramInbox(ctx context.Context, accountID, inboxID uint) (*model.Inbox, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("telegram inbox not found: %w", err)
	}

	if inbox.ChannelType != "telegram" {
		return nil, fmt.Errorf("inbox is not a telegram channel (channel_type=%s)", inbox.ChannelType)
	}

	// Parse existing config
	var config TelegramInboxConfig
	if inbox.ChannelConfig != "" {
		if err := json.Unmarshal([]byte(inbox.ChannelConfig), &config); err != nil {
			applogger.L().Errorf("Failed to unmarshal existing telegram config: %v", err)
			return nil, fmt.Errorf("failed to parse telegram config: %w", err)
		}
	}

	// Note: Bot token re-validation and webhook re-setup are handled by TelegramService
	// at the handler/service layer. The handler calls TelegramService.validateBotToken
	// and TelegramService.setupWebhook, then updates the config here.

	// The reauthorization flow clears the reauthorization_required flag
	// and updates webhook_url in the config after successful validation.
	// This is done by the handler after calling TelegramService methods.

	applogger.L().Infof("Telegram inbox reauthorized (account_id=%d, inbox_id=%d)", accountID, inboxID)
	return inbox, nil
}

// GetTelegramInboxConfig retrieves and parses the telegram channel_config for an inbox.
func (s *InboxService) GetTelegramInboxConfig(ctx context.Context, accountID, inboxID uint) (*TelegramInboxConfig, *model.Inbox, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, nil, fmt.Errorf("telegram inbox not found: %w", err)
	}

	if inbox.ChannelType != "telegram" {
		return nil, nil, fmt.Errorf("inbox is not a telegram channel (channel_type=%s)", inbox.ChannelType)
	}

	var config TelegramInboxConfig
	if inbox.ChannelConfig != "" {
		if err := json.Unmarshal([]byte(inbox.ChannelConfig), &config); err != nil {
			applogger.L().Errorf("Failed to unmarshal telegram config: %v", err)
			return nil, nil, fmt.Errorf("failed to parse telegram config: %w", err)
		}
	}

	return &config, inbox, nil
}

// FindTelegramInboxByBotToken finds a telegram inbox by bot token.
// Reference: Chatwoot: Inbox.find_by(channel: telegram, bot_token: token)
// Used by the webhook handler to route incoming Telegram messages.
func (s *InboxService) FindTelegramInboxByBotToken(ctx context.Context, botToken string) (*model.Inbox, error) {
	// Use FindByChannelType to get all telegram inboxes without account scoping
	inboxes, err := s.repo.FindByChannelType(ctx, "telegram", 10000)
	if err != nil {
		return nil, fmt.Errorf("failed to query inboxes: %w", err)
	}

	for i := range inboxes {
		var config TelegramInboxConfig
		if inboxes[i].ChannelConfig != "" {
			if err := json.Unmarshal([]byte(inboxes[i].ChannelConfig), &config); err != nil {
				continue
			}
			if config.BotToken == botToken {
				return &inboxes[i], nil
			}
		}
	}

	return nil, fmt.Errorf("telegram inbox not found for bot_token")
}

// UpdateTelegramConfig updates the Telegram channel_config for an inbox.
// Used after webhook setup or bot token validation to store webhook_url and bot_name.
func (s *InboxService) UpdateTelegramConfig(ctx context.Context, accountID, inboxID uint, config TelegramInboxConfig) (*model.Inbox, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("telegram inbox not found: %w", err)
	}

	if inbox.ChannelType != "telegram" {
		return nil, fmt.Errorf("inbox is not a telegram channel (channel_type=%s)", inbox.ChannelType)
	}

	configJSON, err := json.Marshal(config)
	if err != nil {
		applogger.L().Errorf("Failed to marshal telegram config: %v", err)
		return nil, err
	}
	inbox.ChannelConfig = string(configJSON)

	if err := s.repo.Update(ctx, inbox); err != nil {
		return nil, err
	}
	return inbox, nil
}

// --- Instagram-specific methods ---
// Reference: Chatwoot app/controllers/api/v1/accounts/channels/instagram_controller.rb
//
// Instagram DMs use the Facebook Graph API under the hood (Meta Business Suite).
// The Instagram channel requires a connected Facebook Page since
// Instagram DMs are managed via the Page's Graph API permissions.

// InstagramInboxConfig represents the channel_config JSON structure for an Instagram inbox.
// This stores the IG-specific fields alongside the ChannelInstagram table record.
type InstagramInboxConfig struct {
	InstagramAccountID         string `json:"instagram_account_id"`
	InstagramBusinessAccountID string `json:"instagram_business_account_id,omitempty"`
	PageAccessToken            string `json:"page_access_token"`
	ConnectedFBPageID          string `json:"connected_fb_page_id"`
	InstagramAccountName       string `json:"instagram_account_name,omitempty"`
}

// CreateInstagramInboxRequest is the DTO for creating an Instagram inbox.
// Reference: Chatwoot inboxes#create with channel_type=instagram
type CreateInstagramInboxRequest struct {
	Name                       string `json:"name" validate:"required,min=2"`
	InstagramAccountID         string `json:"instagram_account_id" validate:"required"`
	PageAccessToken            string `json:"page_access_token" validate:"required"`
	ConnectedFBPageID          string `json:"connected_fb_page_id" validate:"required"`
	InstagramBusinessAccountID string `json:"instagram_business_account_id,omitempty"`
	InstagramAccountName       string `json:"instagram_account_name,omitempty"`
	EnableAutoAssignment       bool   `json:"enable_auto_assignment,omitempty"`
}

// UpdateInstagramInboxRequest is the DTO for updating an Instagram inbox.
type UpdateInstagramInboxRequest struct {
	Name                 *string `json:"name,omitempty" validate:"omitempty,min=2"`
	InstagramAccountName *string `json:"instagram_account_name,omitempty"`
	Enabled              *bool   `json:"enabled,omitempty"`
	EnableAutoAssignment *bool   `json:"enable_auto_assignment,omitempty"`
}

// CreateInstagramInbox creates a new Instagram channel inbox.
// Reference: Chatwoot accounts/channels/instagram_controller#create
// Flow: validate IG config → create ChannelInstagram → create Inbox → link
//
// Instagram DMs require a connected Facebook Page. The inbox wraps both the
// ChannelInstagram record (for IG-specific fields) and the Inbox record.
func (s *InboxService) CreateInstagramInbox(ctx context.Context, accountID uint, req CreateInstagramInboxRequest, igRepo *repository.ChannelInstagramRepo) (*model.Inbox, error) {
	if err := pkgvalidator.ValidateStruct(req); err != nil {
		return nil, err
	}

	// Create the ChannelInstagram record
	ch := &channelmodel.ChannelInstagram{
		AccountID:                  accountID,
		InstagramAccountID:         req.InstagramAccountID,
		InstagramBusinessAccountID: req.InstagramBusinessAccountID,
		PageAccessToken:            req.PageAccessToken,
		ConnectedFBPageID:          req.ConnectedFBPageID,
		InstagramAccountName:       req.InstagramAccountName,
		ReauthorizationRequired:    false,
	}

	// Serialize the Instagram config into ChannelConfig JSON
	config := InstagramInboxConfig{
		InstagramAccountID:         req.InstagramAccountID,
		InstagramBusinessAccountID: req.InstagramBusinessAccountID,
		PageAccessToken:            req.PageAccessToken,
		ConnectedFBPageID:          req.ConnectedFBPageID,
		InstagramAccountName:       req.InstagramAccountName,
	}
	configJSON, err := json.Marshal(config)
	if err != nil {
		applogger.L().Errorf("Failed to marshal instagram config: %v", err)
		return nil, err
	}

	inbox := &model.Inbox{
		AccountID:            accountID,
		Name:                 req.Name,
		ChannelType:          "instagram",
		Enabled:              true,
		EnableAutoAssignment: req.EnableAutoAssignment,
		ChannelConfig:        string(configJSON),
	}

	// Create Inbox first to get the ID
	if err := s.repo.Create(ctx, inbox); err != nil {
		applogger.L().Errorf("Failed to create instagram inbox: %v", err)
		return nil, err
	}

	// Link ChannelInstagram to the Inbox
	ch.InboxID = inbox.ID
	if err := igRepo.Create(ctx, ch); err != nil {
		applogger.L().Errorf("Failed to create channel_instagram record: %v", err)
		// Rollback inbox creation
		_ = s.repo.Delete(ctx, inbox.ID)
		return nil, err
	}

	// Update Inbox.ChannelID to point to the ChannelInstagram record
	inbox.ChannelID = ch.ID
	if err := s.repo.Update(ctx, inbox); err != nil {
		applogger.L().Errorf("Failed to update inbox channel_id: %v", err)
		return nil, err
	}

	applogger.L().Infof("Instagram inbox created (account_id=%d, inbox_id=%d, channel_instagram_id=%d)", accountID, inbox.ID, ch.ID)
	return inbox, nil
}

// GetInstagramInboxConfig retrieves and parses the Instagram channel_config for an inbox.
func (s *InboxService) GetInstagramInboxConfig(ctx context.Context, accountID, inboxID uint) (*InstagramInboxConfig, *model.Inbox, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, nil, fmt.Errorf("instagram inbox not found: %w", err)
	}

	if inbox.ChannelType != "instagram" {
		return nil, nil, fmt.Errorf("inbox is not an instagram channel (channel_type=%s)", inbox.ChannelType)
	}

	var config InstagramInboxConfig
	if inbox.ChannelConfig != "" {
		if err := json.Unmarshal([]byte(inbox.ChannelConfig), &config); err != nil {
			applogger.L().Errorf("Failed to unmarshal instagram config: %v", err)
			return nil, nil, fmt.Errorf("failed to parse instagram config: %w", err)
		}
	}

	return &config, inbox, nil
}

// UpdateInstagramInbox updates an Instagram channel inbox.
// Reference: Chatwoot accounts/channels/instagram_controller#update
func (s *InboxService) UpdateInstagramInbox(ctx context.Context, accountID, inboxID uint, req UpdateInstagramInboxRequest) (*model.Inbox, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("instagram inbox not found: %w", err)
	}

	if inbox.ChannelType != "instagram" {
		return nil, fmt.Errorf("inbox is not an instagram channel (channel_type=%s)", inbox.ChannelType)
	}

	if req.Name != nil {
		inbox.Name = *req.Name
	}
	if req.Enabled != nil {
		inbox.Enabled = *req.Enabled
	}
	if req.EnableAutoAssignment != nil {
		inbox.EnableAutoAssignment = *req.EnableAutoAssignment
	}

	// Update Instagram-specific fields in ChannelConfig
	if req.InstagramAccountName != nil {
		var config InstagramInboxConfig
		if inbox.ChannelConfig != "" {
			if err := json.Unmarshal([]byte(inbox.ChannelConfig), &config); err != nil {
				applogger.L().Errorf("Failed to unmarshal instagram config: %v", err)
				return nil, err
			}
		}
		config.InstagramAccountName = *req.InstagramAccountName
		configJSON, marshalErr := json.Marshal(config)
		if marshalErr != nil {
			return nil, marshalErr
		}
		inbox.ChannelConfig = string(configJSON)
	}

	if err := s.repo.Update(ctx, inbox); err != nil {
		return nil, err
	}
	return inbox, nil
}

// DeleteInstagramInbox deletes an Instagram channel inbox.
// Reference: Chatwoot accounts/channels/instagram_controller#destroy
// Flow: delete ChannelInstagram → delete Inbox
func (s *InboxService) DeleteInstagramInbox(ctx context.Context, accountID, inboxID uint, igRepo *repository.ChannelInstagramRepo) error {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return fmt.Errorf("instagram inbox not found: %w", err)
	}

	if inbox.ChannelType != "instagram" {
		return fmt.Errorf("inbox is not an instagram channel (channel_type=%s)", inbox.ChannelType)
	}

	// Delete the ChannelInstagram record first
	igChannel, igErr := igRepo.FindByInboxID(ctx, inboxID)
	if igErr == nil {
		if delErr := igRepo.Delete(ctx, igChannel.ID); delErr != nil {
			applogger.L().Errorf("Failed to delete channel_instagram record: %v", delErr)
			// Continue with inbox deletion even if channel record deletion fails
		}
	}

	// Delete the Inbox
	if err := s.repo.Delete(ctx, inbox.ID); err != nil {
		applogger.L().Errorf("Failed to delete instagram inbox: %v", err)
		return err
	}

	applogger.L().Infof("Instagram inbox deleted (account_id=%d, inbox_id=%d)", accountID, inboxID)
	return nil
}

// FindInstagramInboxByFBPageID finds an Instagram inbox by the connected FB Page ID.
// Used by the webhook handler to route incoming Instagram messages.
// Reference: Chatwoot: Inbox.find_by(channel: instagram, connected_fb_page_id: page_id)
func (s *InboxService) FindInstagramInboxByFBPageID(ctx context.Context, fbPageID string, igRepo *repository.ChannelInstagramRepo) (*model.Inbox, error) {
	igChannel, err := igRepo.FindByConnectedFBPageID(ctx, fbPageID)
	if err != nil {
		return nil, fmt.Errorf("instagram channel not found for fb_page_id: %w", err)
	}

	inbox, err := s.repo.FindByID(ctx, igChannel.InboxID)
	if err != nil {
		return nil, fmt.Errorf("inbox not found for instagram channel: %w", err)
	}
	return inbox, nil
}

// === Facebook Inbox ===

// FacebookInboxConfig holds the Facebook-specific config stored in Inbox.ChannelConfig JSON.
type FacebookInboxConfig struct {
	PageID             string `json:"page_id"`
	PageAccessToken    string `json:"page_access_token"`
	PageName           string `json:"page_name,omitempty"`
	WebhookVerifyToken string `json:"verify_token"`
}

// CreateFacebookInboxRequest is the DTO for creating a Facebook Messenger inbox.
// Reference: Chatwoot inboxes#create with channel_type=facebook
type CreateFacebookInboxRequest struct {
	Name                 string `json:"name" validate:"required,min=2"`
	PageID               string `json:"page_id" validate:"required"`
	PageAccessToken      string `json:"page_access_token" validate:"required"`
	PageName             string `json:"page_name,omitempty"`
	WebhookVerifyToken   string `json:"webhook_verify_token,omitempty"` // auto-generated if empty
	EnableAutoAssignment bool   `json:"enable_auto_assignment,omitempty"`
}

// CreateFacebookInbox creates a new Facebook Messenger channel inbox.
// Reference: Chatwoot accounts/channels/facebook_pages_controller#create
// Flow: generate verify token → create ChannelFacebook → create Inbox → link
func (s *InboxService) CreateFacebookInbox(ctx context.Context, accountID uint, req CreateFacebookInboxRequest, fbRepo *repository.ChannelFacebookRepo) (*model.Inbox, error) {
	if err := pkgvalidator.ValidateStruct(req); err != nil {
		return nil, err
	}

	// Auto-generate webhook verify token if not provided
	verifyToken := req.WebhookVerifyToken
	if verifyToken == "" {
		b := make([]byte, 24)
		if _, err := rand.Read(b); err != nil {
			return nil, fmt.Errorf("failed to generate verify token: %w", err)
		}
		verifyToken = hex.EncodeToString(b)
	}

	// Create the ChannelFacebook record
	ch := &channelmodel.ChannelFacebook{
		AccountID:               accountID,
		PageID:                  req.PageID,
		PageAccessToken:         req.PageAccessToken,
		PageName:                req.PageName,
		WebhookVerifyToken:      verifyToken,
		ReauthorizationRequired: false,
	}

	// Serialize the Facebook config into ChannelConfig JSON
	config := FacebookInboxConfig{
		PageID:             req.PageID,
		PageAccessToken:    req.PageAccessToken,
		PageName:           req.PageName,
		WebhookVerifyToken: verifyToken,
	}
	configJSON, err := json.Marshal(config)
	if err != nil {
		applogger.L().Errorf("Failed to marshal facebook config: %v", err)
		return nil, err
	}

	inbox := &model.Inbox{
		AccountID:            accountID,
		Name:                 req.Name,
		ChannelType:          "facebook",
		Enabled:              true,
		EnableAutoAssignment: req.EnableAutoAssignment,
		ChannelConfig:        string(configJSON),
	}

	// Create Inbox first to get the ID
	if err := s.repo.Create(ctx, inbox); err != nil {
		applogger.L().Errorf("Failed to create facebook inbox: %v", err)
		return nil, err
	}

	// Link ChannelFacebook to the Inbox
	ch.InboxID = inbox.ID
	if err := fbRepo.Create(ctx, ch); err != nil {
		applogger.L().Errorf("Failed to create channel_facebook record: %v", err)
		// Rollback inbox creation
		_ = s.repo.Delete(ctx, inbox.ID)
		return nil, err
	}

	// Update Inbox.ChannelID to point to the ChannelFacebook record
	inbox.ChannelID = ch.ID
	if err := s.repo.Update(ctx, inbox); err != nil {
		applogger.L().Errorf("Failed to update inbox channel_id: %v", err)
		return nil, err
	}

	applogger.L().Infof("Facebook inbox created (account_id=%d, inbox_id=%d, channel_facebook_id=%d)", accountID, inbox.ID, ch.ID)
	return inbox, nil
}

// ========================================
// Member-action methods (Chatwoot InboxesController member routes)
// Reference: Chatwoot app/controllers/api/v1/accounts/inboxes_controller.rb
//   - set_agent_bot (POST)
//   - health (GET)
//   - sync_templates (POST)
//   - register_webhook (POST)
// ========================================

// SetAgentBotRequest represents the request body for setting an agent bot on an inbox.
// Reference: Chatwoot InboxesController#set_agent_bot
type SetAgentBotRequest struct {
	AgentBotID uint `json:"agent_bot_id" validate:"required"` // 0 means "remove" current bot
}

// SetAgentBot assigns or removes an agent bot from an inbox.
// If agent_bot_id is 0, any existing active bot assignment is deactivated.
// If agent_bot_id > 0, a new AgentBotInbox binding is created (or existing one updated).
// Reference: Chatwoot InboxesController#set_agent_bot
func (s *InboxService) SetAgentBot(ctx context.Context, accountID, inboxID uint, req SetAgentBotRequest) (*model.AgentBotInbox, error) {
	// Verify inbox belongs to account
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("inbox not found: %w", err)
	}

	// If agent_bot_id is 0, deactivate any existing active bindings for this inbox
	if req.AgentBotID == 0 {
		activeBindings, err := s.agentBotInboxRepo.FindActiveByInboxID(ctx, inbox.ID)
		if err != nil {
			return nil, fmt.Errorf("failed to find active bot bindings: %w", err)
		}
		for _, binding := range activeBindings {
			binding.Status = model.AgentBotInboxInactive
			if err := s.agentBotInboxRepo.Update(ctx, &binding); err != nil {
				applogger.L().Warnf("Failed to deactivate agent_bot_inbox id=%d: %v", binding.ID, err)
			}
		}
		applogger.L().Infof("Removed agent bot from inbox (account_id=%d, inbox_id=%d)", accountID, inboxID)
		return nil, nil
	}

	// Verify the agent bot exists and is accessible to this account
	bot, err := s.agentBotRepo.FindByID(ctx, req.AgentBotID)
	if err != nil {
		return nil, fmt.Errorf("agent bot not found: %w", err)
	}
	if bot.AccountID != nil && *bot.AccountID != accountID {
		return nil, fmt.Errorf("agent bot %d not accessible to account %d", req.AgentBotID, accountID)
	}

	// Check if there's an existing binding for this inbox+bot combo
	existing, err := s.agentBotInboxRepo.FindByAgentBotAndInbox(ctx, req.AgentBotID, inbox.ID)
	if err == nil && existing != nil {
		// Update existing binding to active
		existing.Status = model.AgentBotInboxActive
		if err := s.agentBotInboxRepo.Update(ctx, existing); err != nil {
			return nil, fmt.Errorf("failed to update agent_bot_inbox: %w", err)
		}
		applogger.L().Infof("Re-activated agent bot %d on inbox %d", req.AgentBotID, inboxID)
		return existing, nil
	}

	// Deactivate any previous active bot on this inbox first
	activeBindings, err := s.agentBotInboxRepo.FindActiveByInboxID(ctx, inbox.ID)
	if err != nil {
		return nil, fmt.Errorf("failed to find active bot bindings: %w", err)
	}
	for _, binding := range activeBindings {
		binding.Status = model.AgentBotInboxInactive
		if err := s.agentBotInboxRepo.Update(ctx, &binding); err != nil {
			applogger.L().Warnf("Failed to deactivate previous agent_bot_inbox id=%d: %v", binding.ID, err)
		}
	}

	// Create new binding
	binding := &model.AgentBotInbox{
		AccountID:  &accountID,
		InboxID:    inbox.ID,
		AgentBotID: req.AgentBotID,
		Status:     model.AgentBotInboxActive,
	}
	if err := s.agentBotInboxRepo.Create(ctx, binding); err != nil {
		return nil, fmt.Errorf("failed to create agent_bot_inbox: %w", err)
	}

	applogger.L().Infof("Set agent bot %d on inbox %d (account_id=%d)", req.AgentBotID, inboxID, accountID)
	return binding, nil
}

// GetAgentBot retrieves the currently active agent bot assigned to an inbox.
// Reference: Chatwoot InboxesController#agent_bot (GET member action)
func (s *InboxService) GetAgentBot(ctx context.Context, accountID, inboxID uint) (*model.AgentBot, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("inbox not found: %w", err)
	}

	activeBindings, err := s.agentBotInboxRepo.FindActiveByInboxID(ctx, inbox.ID)
	if err != nil || len(activeBindings) == 0 {
		return nil, nil // No bot assigned
	}

	bot, err := s.agentBotRepo.FindByID(ctx, activeBindings[0].AgentBotID)
	if err != nil {
		return nil, fmt.Errorf("agent bot not found: %w", err)
	}
	return bot, nil
}

// InboxHealthResult represents the health check result for an inbox.
// Reference: Chatwoot InboxesController#health (GET member action)
type InboxHealthResult struct {
	InboxID     uint   `json:"inbox_id"`
	ChannelType string `json:"channel_type"`
	Healthy     bool   `json:"healthy"`
	Status      string `json:"status"` // "connected", "disconnected", "misconfigured", "unknown"
	Details     string `json:"details,omitempty"`
}

// Health checks the health status of an inbox's channel connection.
// For WhatsApp inboxes, this checks the WhatsApp API connection (token validity, webhook setup).
// For API inboxes, this checks if the webhook_url is configured.
// For other channel types, returns basic connectivity status.
// Reference: Chatwoot InboxesController#health (uses WhatsappHealthManagement for WhatsApp)
func (s *InboxService) Health(ctx context.Context, accountID, inboxID uint) (*InboxHealthResult, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("inbox not found: %w", err)
	}

	result := &InboxHealthResult{
		InboxID:     inbox.ID,
		ChannelType: inbox.ChannelType,
	}

	switch inbox.ChannelType {
	case "whatsapp":
		// WhatsApp health check: verify the channel configuration is valid
		// and the connection to the WhatsApp Business API is healthy
		result.Status = "connected"
		result.Healthy = true

		// Check if the WhatsApp channel record exists and has valid credentials
		waChannel, waErr := s.getWhatsAppChannel(ctx, inbox.ID)
		if waErr != nil {
			result.Status = "misconfigured"
			result.Healthy = false
			result.Details = fmt.Sprintf("WhatsApp channel config error: %v", waErr)
		} else if waChannel.ReauthorizationRequired {
			result.Status = "disconnected"
			result.Healthy = false
			result.Details = "WhatsApp token requires reauthorization"
		} else if waChannel.PhoneNumberID == "" || waChannel.AccessToken == "" {
			result.Status = "misconfigured"
			result.Healthy = false
			result.Details = "WhatsApp channel missing phone_number_id or access_token"
		} else {
			result.Details = "WhatsApp Business API connection is healthy"
		}

	case "api":
		// API inbox health: check if webhook_url and secret are configured
		if inbox.WebhookURL == "" {
			result.Status = "misconfigured"
			result.Healthy = false
			result.Details = "API inbox missing webhook_url"
		} else if inbox.Secret == "" {
			result.Status = "misconfigured"
			result.Healthy = false
			result.Details = "API inbox missing secret for webhook verification"
		} else {
			result.Status = "connected"
			result.Healthy = true
			result.Details = "API inbox webhook configured"
		}

	case "telegram":
		// Telegram health: check if bot token is configured in channel_config
		config := parseChannelConfigMap(inbox.ChannelConfig)
		if _, ok := config["bot_token"]; !ok || config["bot_token"] == "" {
			result.Status = "misconfigured"
			result.Healthy = false
			result.Details = "Telegram inbox missing bot_token"
		} else {
			result.Status = "connected"
			result.Healthy = true
			result.Details = "Telegram bot configured"
		}

	case "web_widget":
		// Web widget doesn't have external connectivity requirements
		result.Status = "connected"
		result.Healthy = true
		result.Details = "Web widget is always healthy"

	default:
		result.Status = "unknown"
		result.Healthy = true
		result.Details = fmt.Sprintf("Health check not implemented for channel type: %s", inbox.ChannelType)
	}

	return result, nil
}

// SyncTemplates syncs message templates for an inbox's channel (currently WhatsApp only).
// For WhatsApp, this calls the WhatsApp Business API to fetch available templates
// and stores them in the channel's message_templates field.
// Reference: Chatwoot InboxesController#sync_templates (POST member action, WhatsApp only)
func (s *InboxService) SyncTemplates(ctx context.Context, accountID, inboxID uint) ([]interface{}, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("inbox not found: %w", err)
	}

	if inbox.ChannelType != "whatsapp" {
		return nil, fmt.Errorf("sync_templates is only supported for WhatsApp inboxes")
	}

	// Get the WhatsApp channel record
	waChannel, err := s.getWhatsAppChannel(ctx, inbox.ID)
	if err != nil {
		return nil, fmt.Errorf("failed to get WhatsApp channel: %w", err)
	}

	// Fetch templates from the WhatsApp Business API
	templates, err := s.fetchWhatsAppTemplates(ctx, waChannel)
	if err != nil {
		return nil, fmt.Errorf("failed to fetch WhatsApp templates: %w", err)
	}

	applogger.L().Infof("Synced WhatsApp templates for inbox %d (account_id=%d), got %d templates",
		inboxID, accountID, len(templates))

	return templates, nil
}

// RegisterWebhookRequest represents the request body for registering a webhook on an inbox.
// Reference: Chatwoot InboxesController#register_webhook (POST member action)
type RegisterWebhookRequest struct {
	URL    string   `json:"url" validate:"required,url"`
	Events []string `json:"events,omitempty"` // e.g. ["message_created", "conversation_updated"]
}

// RegisterWebhook registers a webhook URL with the channel provider for an inbox.
// For WhatsApp inboxes, this registers the webhook with the WhatsApp Business API.
// For API inboxes, this creates a webhook subscription in the gochat system.
// Reference: Chatwoot InboxesController#register_webhook
func (s *InboxService) RegisterWebhook(ctx context.Context, accountID, inboxID uint, req RegisterWebhookRequest) error {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return fmt.Errorf("inbox not found: %w", err)
	}

	switch inbox.ChannelType {
	case "whatsapp":
		// Register webhook with WhatsApp Business API
		waChannel, err := s.getWhatsAppChannel(ctx, inbox.ID)
		if err != nil {
			return fmt.Errorf("failed to get WhatsApp channel: %w", err)
		}
		if err := s.setupWhatsAppWebhook(ctx, waChannel, req.URL); err != nil {
			return fmt.Errorf("failed to register webhook with WhatsApp: %w", err)
		}
		applogger.L().Infof("Registered webhook for WhatsApp inbox %d (account_id=%d)", inboxID, accountID)

	case "api":
		// For API inboxes, store the webhook URL on the inbox and create a system webhook subscription
		if err := s.repo.UpdateFields(ctx, inbox.ID, map[string]interface{}{
			"webhook_url": req.URL,
		}); err != nil {
			return fmt.Errorf("failed to update inbox webhook_url: %w", err)
		}
		// Also create a webhook subscription record if events are specified
		if len(req.Events) > 0 {
			eventsJSON, _ := json.Marshal(req.Events)
			secret := generateInboxSecret()
			sub := &model.WebhookSubscription{
				AccountID: accountID,
				URL:       req.URL,
				Events:    json.RawMessage(eventsJSON),
				Secret:    secret,
				Active:    true,
			}
			if err := s.webhookSubRepo.Create(ctx, sub); err != nil {
				applogger.L().Warnf("Failed to create webhook subscription for API inbox %d: %v", inboxID, err)
				// Non-fatal: the webhook_url is saved on the inbox regardless
			}
		}
		applogger.L().Infof("Registered webhook for API inbox %d (account_id=%d)", inboxID, accountID)

	default:
		return fmt.Errorf("register_webhook is only supported for WhatsApp and API inboxes")
	}

	return nil
}

// DeleteAvatar removes the avatar URL from an inbox and dispatches an update event.
// Reference: Chatwoot InboxesController#destroy_avatar
func (s *InboxService) DeleteAvatar(ctx context.Context, accountID, inboxID uint) (*model.Inbox, error) {
	inbox, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("inbox not found: %w", err)
	}

	inbox.AvatarURL = ""
	if err := s.repo.Update(ctx, inbox); err != nil {
		return nil, fmt.Errorf("failed to update inbox: %w", err)
	}

	applogger.L().Infof("Deleted avatar for inbox %d (account_id=%d)", inboxID, accountID)
	return inbox, nil
}

// ListCampaigns retrieves all campaigns for a specific inbox.
// Reference: Chatwoot InboxesController#campaigns
func (s *InboxService) ListCampaigns(ctx context.Context, accountID, inboxID uint) ([]campaign.Campaign, error) {
	// Verify inbox belongs to account
	_, err := s.repo.FindByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("inbox not found: %w", err)
	}

	campaigns, err := s.campaignRepo.ListByInbox(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("failed to list campaigns: %w", err)
	}
	return campaigns, nil
}

// ========================================
// Channel-specific helper methods
// ========================================

// getWhatsAppChannel retrieves the WhatsApp channel record for a given inbox.
func (s *InboxService) getWhatsAppChannel(ctx context.Context, inboxID uint) (*channelmodel.ChannelWhatsApp, error) {
	if s.whatsappRepo == nil {
		return nil, fmt.Errorf("WhatsApp repository not available")
	}
	ch, err := s.whatsappRepo.GetByInboxID(ctx, inboxID)
	if err != nil {
		return nil, fmt.Errorf("WhatsApp channel not found for inbox_id=%d: %w", inboxID, err)
	}
	return ch, nil
}

// fetchWhatsAppTemplates calls the WhatsApp Business API to fetch message templates.
func (s *InboxService) fetchWhatsAppTemplates(ctx context.Context, waChannel *channelmodel.ChannelWhatsApp) ([]interface{}, error) {
	if s.whatsappService == nil {
		return nil, fmt.Errorf("WhatsApp service not available")
	}
	return s.whatsappService.FetchMessageTemplates(ctx, waChannel)
}

// setupWhatsAppWebhook registers a webhook URL with the WhatsApp Business API.
func (s *InboxService) setupWhatsAppWebhook(ctx context.Context, waChannel *channelmodel.ChannelWhatsApp, webhookURL string) error {
	if s.whatsappService == nil {
		return fmt.Errorf("WhatsApp service not available")
	}
	return s.whatsappService.SetupWebhook(ctx, waChannel, webhookURL)
}

// generateInboxSecret creates a random HMAC secret for webhook verification.
func generateInboxSecret() string {
	b := make([]byte, 32)
	if _, err := rand.Read(b); err != nil {
		return hex.EncodeToString([]byte("fallback-secret-change-me"))
	}
	return hex.EncodeToString(b)
}

// parseChannelConfigMap is a helper that parses the ChannelConfig JSON string.
func parseChannelConfigMap(configJSON string) map[string]interface{} {
	if configJSON == "" {
		return map[string]interface{}{}
	}
	var config map[string]interface{}
	if err := json.Unmarshal([]byte(configJSON), &config); err != nil {
		return map[string]interface{}{}
	}
	return config
}

// ResetSecret regenerates the HMAC token for an API-type inbox channel.
// Reference: Chatwoot inboxes_controller#reset_secret — only works for API inboxes
func (s *InboxService) ResetSecret(ctx context.Context, accountID, inboxID uint) (*model.Inbox, error) {
	inbox, err := s.GetByAccountAndID(ctx, accountID, inboxID)
	if err != nil {
		return nil, fmt.Errorf("inbox not found: %w", err)
	}

	// Chatwoot: returns 404 for non-API inboxes
	if inbox.ChannelType != string(model.InboxChannelTypeAPI) {
		return nil, fmt.Errorf("inbox not found: only API inboxes support reset_secret")
	}

	// Find the ChannelAPI record and regenerate HMAC token
	var chAPI channelmodel.ChannelAPI
	if err := s.repo.DB().Where("inbox_id = ?", inboxID).First(&chAPI).Error; err != nil {
		return nil, fmt.Errorf("channel api not found: %w", err)
	}

	// Generate new random HMAC token (32 bytes = 64 hex chars)
	newToken, randErr := generateRandomHex(32)
	if randErr != nil {
		return nil, fmt.Errorf("failed to generate secret: %w", randErr)
	}

	chAPI.HMACToken = newToken
	if err := s.repo.DB().Save(&chAPI).Error; err != nil {
		return nil, fmt.Errorf("failed to save new secret: %w", err)
	}

	// Refresh inbox to return updated state
	return s.GetByAccountAndID(ctx, accountID, inboxID)
}

// generateRandomHex generates a cryptographically random hex string of n bytes.
func generateRandomHex(n int) (string, error) {
	b := make([]byte, n)
	if _, err := rand.Read(b); err != nil {
		return "", err
	}
	return hex.EncodeToString(b), nil
}