package v1

import (
	"net/http"
	"strings"

	"github.com/gin-gonic/gin"

	"github.com/gochat/gochat/internal/model"
	"github.com/gochat/gochat/internal/search"
	"github.com/gochat/gochat/pkg/response"
)

const chatwootSearchPerPage = 15

// SearchHandler handles global search API endpoints.
// Reference: Chatwoot GlobalSearchService — cross-entity search with advanced filtering.
type SearchHandler struct {
	svc *search.SearchService
}

// NewSearchHandler creates a new SearchHandler.
func NewSearchHandler(svc *search.SearchService) *SearchHandler {
	return &SearchHandler{svc: svc}
}

// GlobalSearch performs a unified search across conversations, messages, and contacts.
// GET /api/v1/accounts/:account_id/search?q=xxx&types=conversation,message&status=open&assignee_id=1
// Reference: Chatwoot GlobalSearchService — searches across conversations, messages, contacts.

// @Summary Global search across all entity types
// @Description Searches across conversations, messages, contacts, and articles with advanced filtering and pagination
// @Tags Search
// @Accept json
// @Produce json
// @Param account_id path uint true "Account ID"
// @Param q query string false "Search query string"
// @Param types query string false "Entity types to search (conversation,message,contact,article)" default(conversation,message,contact,article)
// @Param search_mode query string false "Search mode: ilike (substring) or trigram (fuzzy)" default(ilike)
// @Param status query string false "Conversation status filter (open,resolved,pending,snoozed)"
// @Param priority query string false "Conversation priority filter (none,low,medium,high,urgent)"
// @Param assignee_id query int false "Assignee agent ID filter"
// @Param team_id query int false "Team ID filter"
// @Param inbox_id query int false "Inbox ID filter"
// @Param labels query string false "Label filter (comma-separated)"
// @Param contact_source query string false "Contact source filter (email,phone,website,api)"
// @Param message_type query string false "Message type filter (incoming,outgoing,activity)"
// @Param sender_type query string false "Sender type filter"
// @Param content_type query string false "Content type filter (text,input_email,card)"
// @Param private query bool false "Private message filter"
// @Param date_from query string false "Date range start (ISO 8601)"
// @Param date_to query string false "Date range end (ISO 8601)"
// @Param portal_id query int false "Portal ID filter (for article search)"
// @Param article_status query string false "Article status filter (draft,published,archived)"
// @Param article_locale query string false "Article locale filter"
// @Param sort_by query string false "Sort field (created_at,last_activity_at,updated_at)" default(created_at)
// @Param sort_order query string false "Sort order (asc,desc)" default(desc)
// @Param page query int false "Page number" default(1)
// @Param per_page query int false "Items per page" default(25)
// @Success 200 {object} search.SearchResponse
// @Failure 400 {object} model.ErrorResponse
// @Failure 401 {object} model.ErrorResponse
// @Failure 500 {object} model.ErrorResponse
// @Security ApiKeyAuth
// @Router /api/v1/accounts/{account_id}/search [get]
func (h *SearchHandler) GlobalSearch(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account id")
		return
	}

	query := c.Query("q")
	filter := parseChatwootSearchFilter(c)

	result, svcErr := h.svc.GlobalSearch(c.Request.Context(), accountID, query, &filter)
	if svcErr != nil {
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "search failed")
		return
	}

	c.JSON(http.StatusOK, gin.H{"payload": serializeSearchPayload(result.Results)})
}

// SearchConversations performs a conversation-only search with advanced filters.
// GET /api/v1/accounts/:account_id/search/conversations?q=xxx&status=open&assignee_id=1
// Reference: Chatwoot conversations#index with filter params.

// @Summary Search conversations
// @Description Searches conversations by query string with advanced filtering (status, assignee, labels, date range)
// @Tags Search
// @Accept json
// @Produce json
// @Param account_id path uint true "Account ID"
// @Param q query string true "Search query string"
// @Param search_mode query string false "Search mode: ilike (substring) or trigram (fuzzy)" default(ilike)
// @Param status query string false "Conversation status filter (open,resolved,pending,snoozed)"
// @Param priority query string false "Conversation priority filter (none,low,medium,high,urgent)"
// @Param assignee_id query int false "Assignee agent ID filter"
// @Param team_id query int false "Team ID filter"
// @Param inbox_id query int false "Inbox ID filter"
// @Param labels query string false "Label filter (comma-separated)"
// @Param date_from query string false "Date range start (ISO 8601)"
// @Param date_to query string false "Date range end (ISO 8601)"
// @Param sort_by query string false "Sort field (created_at,last_activity_at,updated_at)" default(created_at)
// @Param sort_order query string false "Sort order (asc,desc)" default(desc)
// @Param page query int false "Page number" default(1)
// @Param per_page query int false "Items per page" default(25)
// @Success 200 {object} map[string]interface{}
// @Failure 400 {object} model.ErrorResponse
// @Failure 401 {object} model.ErrorResponse
// @Failure 500 {object} model.ErrorResponse
// @Security ApiKeyAuth
// @Router /api/v1/accounts/{account_id}/search/conversations [get]
func (h *SearchHandler) SearchConversations(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account id")
		return
	}

	query := c.Query("q")
	filter := parseChatwootSearchFilter(c)
	// Force type to conversations only
	filter.Types = []search.SearchResultType{search.ResultTypeConversation}

	results, total, svcErr := h.svc.SearchConversations(c.Request.Context(), accountID, query, &filter)
	if svcErr != nil {
		response.AbortWithStatusError(c, http.StatusUnprocessableEntity, response.ErrValidation, "conversation search failed")
		return
	}

	_ = total
	c.JSON(http.StatusOK, gin.H{"payload": gin.H{"conversations": serializeSearchConversations(results)}})
}

// SearchMessages performs a message-only search with advanced filters.
// GET /api/v1/accounts/:account_id/search/messages?q=xxx&message_type=incoming&private=false
// Reference: Chatwoot messages search — full text search on message content.

// @Summary Search messages
// @Description Searches messages by query string with advanced filtering (message type, sender type, content type, private)
// @Tags Search
// @Accept json
// @Produce json
// @Param account_id path uint true "Account ID"
// @Param q query string true "Search query string"
// @Param search_mode query string false "Search mode: ilike (substring) or trigram (fuzzy)" default(ilike)
// @Param message_type query string false "Message type filter (incoming,outgoing,activity)"
// @Param sender_type query string false "Sender type filter"
// @Param content_type query string false "Content type filter (text,input_email,card)"
// @Param private query bool false "Private message filter"
// @Param inbox_id query int false "Inbox ID filter"
// @Param date_from query string false "Date range start (ISO 8601)"
// @Param date_to query string false "Date range end (ISO 8601)"
// @Param sort_by query string false "Sort field (created_at,updated_at)" default(created_at)
// @Param sort_order query string false "Sort order (asc,desc)" default(desc)
// @Param page query int false "Page number" default(1)
// @Param per_page query int false "Items per page" default(25)
// @Success 200 {object} map[string]interface{}
// @Failure 400 {object} model.ErrorResponse
// @Failure 401 {object} model.ErrorResponse
// @Failure 500 {object} model.ErrorResponse
// @Security ApiKeyAuth
// @Router /api/v1/accounts/{account_id}/search/messages [get]
func (h *SearchHandler) SearchMessages(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account id")
		return
	}

	query := c.Query("q")
	filter := parseChatwootSearchFilter(c)
	// Force type to messages only
	filter.Types = []search.SearchResultType{search.ResultTypeMessage}

	results, total, svcErr := h.svc.SearchMessages(c.Request.Context(), accountID, query, &filter)
	if svcErr != nil {
		response.AbortWithStatusError(c, http.StatusUnprocessableEntity, response.ErrValidation, "message search failed")
		return
	}

	_ = total
	c.JSON(http.StatusOK, gin.H{"payload": gin.H{"messages": serializeSearchMessages(results)}})
}

// SearchContacts performs a contact-only search with advanced filters.
// GET /api/v1/accounts/:account_id/search/contacts?q=xxx&contact_source=email
// Reference: Chatwoot contacts#search — name, email, phone, identifier.

// @Summary Search contacts
// @Description Searches contacts by query string (name, email, phone, identifier) with advanced filtering
// @Tags Search
// @Accept json
// @Produce json
// @Param account_id path uint true "Account ID"
// @Param q query string true "Search query string"
// @Param search_mode query string false "Search mode: ilike (substring) or trigram (fuzzy)" default(ilike)
// @Param contact_source query string false "Contact source filter (email,phone,website,api)"
// @Param sort_by query string false "Sort field (created_at,updated_at,name)" default(created_at)
// @Param sort_order query string false "Sort order (asc,desc)" default(desc)
// @Param page query int false "Page number" default(1)
// @Param per_page query int false "Items per page" default(25)
// @Success 200 {object} map[string]interface{}
// @Failure 400 {object} model.ErrorResponse
// @Failure 401 {object} model.ErrorResponse
// @Failure 500 {object} model.ErrorResponse
// @Security ApiKeyAuth
// @Router /api/v1/accounts/{account_id}/search/contacts [get]
func (h *SearchHandler) SearchContacts(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account id")
		return
	}

	query := c.Query("q")
	filter := parseChatwootSearchFilter(c)
	// Force type to contacts only
	filter.Types = []search.SearchResultType{search.ResultTypeContact}

	results, total, svcErr := h.svc.SearchContacts(c.Request.Context(), accountID, query, &filter)
	if svcErr != nil {
		response.AbortWithStatusError(c, http.StatusUnprocessableEntity, response.ErrValidation, "contact search failed")
		return
	}

	_ = total
	c.JSON(http.StatusOK, gin.H{"payload": gin.H{"contacts": serializeSearchContacts(results)}})
}

// SearchArticles performs a knowledge base article-only search with advanced filters.
// GET /api/v1/accounts/:account_id/search/articles?q=xxx&portal_id=1&article_status=published&locale=en
// Reference: Chatwoot ArticlesController#search — full text search on article title, description, content.

// @Summary Search knowledge base articles
// @Description Searches knowledge base articles by query string (title, description, content) with portal, status, and locale filters
// @Tags Search
// @Accept json
// @Produce json
// @Param account_id path uint true "Account ID"
// @Param q query string true "Search query string"
// @Param search_mode query string false "Search mode: ilike (substring) or trigram (fuzzy)" default(ilike)
// @Param portal_id query int false "Portal ID filter"
// @Param article_status query string false "Article status filter (draft,published,archived)"
// @Param article_locale query string false "Article locale filter (en,es,fr,de,pt,etc)"
// @Param author_id query int false "Author ID filter"
// @Param sort_by query string false "Sort field (created_at,updated_at)" default(created_at)
// @Param sort_order query string false "Sort order (asc,desc)" default(desc)
// @Param page query int false "Page number" default(1)
// @Param per_page query int false "Items per page" default(25)
// @Success 200 {object} map[string]interface{}
// @Failure 400 {object} model.ErrorResponse
// @Failure 401 {object} model.ErrorResponse
// @Failure 500 {object} model.ErrorResponse
// @Security ApiKeyAuth
// @Router /api/v1/accounts/{account_id}/search/articles [get]
func (h *SearchHandler) SearchArticles(c *gin.Context) {
	accountID, err := parseUintParam(c, "account_id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid account id")
		return
	}

	query := c.Query("q")
	filter := parseChatwootSearchFilter(c)
	// Force type to articles only
	filter.Types = []search.SearchResultType{search.ResultTypeArticle}

	results, total, svcErr := h.svc.SearchArticles(c.Request.Context(), accountID, query, &filter)
	if svcErr != nil {
		response.AbortWithStatusError(c, http.StatusUnprocessableEntity, response.ErrValidation, "article search failed")
		return
	}

	_ = total
	c.JSON(http.StatusOK, gin.H{"payload": gin.H{"articles": serializeSearchArticles(results)}})
}

func serializeSearchPayload(results []search.SearchResult) gin.H {
	return gin.H{
		"conversations": serializeSearchConversations(filterSearchResults(results, search.ResultTypeConversation)),
		"contacts":      serializeSearchContacts(filterSearchResults(results, search.ResultTypeContact)),
		"messages":      serializeSearchMessages(filterSearchResults(results, search.ResultTypeMessage)),
		"articles":      serializeSearchArticles(filterSearchResults(results, search.ResultTypeArticle)),
	}
}

func parseChatwootSearchFilter(c *gin.Context) search.SearchFilter {
	filter := search.ParseSearchFilter(c)
	if c.Query("per_page") == "" {
		filter.PerPage = chatwootSearchPerPage
	}
	return filter
}

func filterSearchResults(results []search.SearchResult, resultType search.SearchResultType) []search.SearchResult {
	filtered := make([]search.SearchResult, 0)
	for _, result := range results {
		if result.Type == resultType {
			filtered = append(filtered, result)
		}
	}
	return filtered
}

func serializeSearchConversations(results []search.SearchResult) []map[string]any {
	payload := make([]map[string]any, 0, len(results))
	for _, result := range results {
		payload = append(payload, serializeSearchConversation(result))
	}
	return payload
}

func serializeSearchConversation(result search.SearchResult) map[string]any {
	if conv, ok := result.Data.(model.Conversation); ok {
		return map[string]any{
			"id":                    conversationDisplayID(&conv),
			"account_id":            conv.AccountID,
			"created_at":            conv.CreatedAt.Unix(),
			"additional_attributes": jsonObject(conv.AdditionalAttributes),
		}
	}
	if conv, ok := result.Data.(*model.Conversation); ok && conv != nil {
		return map[string]any{
			"id":                    conversationDisplayID(conv),
			"account_id":            conv.AccountID,
			"created_at":            conv.CreatedAt.Unix(),
			"additional_attributes": jsonObject(conv.AdditionalAttributes),
		}
	}
	data := nestedSearchData(result, "conversation")
	return map[string]any{
		"id":                    firstMapValue(data, "display_id", "id"),
		"account_id":            firstMapValue(data, "account_id"),
		"created_at":            unixFromMapValue(firstMapValue(data, "created_at", "created_at_ts")),
		"additional_attributes": firstMapValue(data, "additional_attributes"),
	}
}

func serializeSearchContacts(results []search.SearchResult) []map[string]any {
	payload := make([]map[string]any, 0, len(results))
	for _, result := range results {
		payload = append(payload, serializeSearchContact(result))
	}
	return payload
}

func serializeSearchContact(result search.SearchResult) map[string]any {
	if contact, ok := result.Data.(model.Contact); ok {
		return serializeSearchContactModel(&contact)
	}
	if contact, ok := result.Data.(*model.Contact); ok && contact != nil {
		return serializeSearchContactModel(contact)
	}
	data := nestedSearchData(result, "contact")
	return map[string]any{
		"email":                 firstMapValue(data, "email"),
		"id":                    firstMapValue(data, "id"),
		"name":                  firstMapValue(data, "name"),
		"phone_number":          firstMapValue(data, "phone_number"),
		"identifier":            firstMapValue(data, "identifier"),
		"additional_attributes": firstMapValue(data, "additional_attributes"),
		"last_activity_at":      unixFromMapValue(firstMapValue(data, "last_activity_at")),
	}
}

func serializeSearchContactModel(contact *model.Contact) map[string]any {
	return map[string]any{
		"email":                 contact.Email,
		"id":                    contact.ID,
		"name":                  contact.Name,
		"phone_number":          contact.PhoneNumber,
		"identifier":            contact.Identifier,
		"additional_attributes": jsonObject(contact.AdditionalAttributes),
		"last_activity_at":      int64Value(contact.LastActivityAt),
	}
}

func serializeSearchMessages(results []search.SearchResult) []map[string]any {
	payload := make([]map[string]any, 0, len(results))
	for _, result := range results {
		payload = append(payload, serializeSearchMessage(result))
	}
	return payload
}

func serializeSearchMessage(result search.SearchResult) map[string]any {
	if message, ok := result.Data.(model.Message); ok {
		return serializeSearchMessageModel(&message)
	}
	if message, ok := result.Data.(*model.Message); ok && message != nil {
		return serializeSearchMessageModel(message)
	}
	data := nestedSearchData(result, "message")
	return map[string]any{
		"id":                    firstMapValue(data, "id"),
		"content":               firstMapValue(data, "content"),
		"account_id":            firstMapValue(data, "account_id"),
		"inbox_id":              firstMapValue(data, "inbox_id"),
		"conversation_id":       firstMapValue(data, "conversation_id"),
		"message_type":          normalizeSearchMessageType(firstMapValue(data, "message_type")),
		"content_type":          firstMapValue(data, "content_type"),
		"status":                firstMapValue(data, "status"),
		"content_attributes":    firstMapValue(data, "content_attributes"),
		"additional_attributes": firstMapValue(data, "additional_attributes"),
		"created_at":            unixFromMapValue(firstMapValue(data, "created_at", "created_at_ts")),
		"private":               firstMapValue(data, "private"),
		"source_id":             firstMapValue(data, "source_id"),
	}
}

func normalizeSearchMessageType(value any) any {
	s, ok := value.(string)
	if !ok {
		return value
	}
	if strings.TrimSpace(s) == "" {
		return value
	}
	return messageTypeValue(s)
}

func serializeSearchMessageModel(message *model.Message) map[string]any {
	return map[string]any{
		"id":                    message.ID,
		"content":               message.Content,
		"account_id":            message.AccountID,
		"inbox_id":              message.InboxID,
		"conversation_id":       message.ConversationID,
		"message_type":          messageTypeValue(message.MessageType),
		"content_type":          nonEmpty(message.ContentType, "text"),
		"status":                nonEmpty(message.Status, "sent"),
		"content_attributes":    jsonObject(message.ContentAttributes),
		"additional_attributes": jsonObject(message.AdditionalAttributes),
		"created_at":            message.CreatedAt.Unix(),
		"private":               message.Private,
		"source_id":             message.SourceID,
	}
}

func serializeSearchArticles(results []search.SearchResult) []map[string]any {
	payload := make([]map[string]any, 0, len(results))
	for _, result := range results {
		payload = append(payload, serializeSearchArticle(result))
	}
	return payload
}

func serializeSearchArticle(result search.SearchResult) map[string]any {
	if article, ok := result.Data.(model.Article); ok {
		return serializeSearchArticleModel(&article)
	}
	if article, ok := result.Data.(*model.Article); ok && article != nil {
		return serializeSearchArticleModel(article)
	}
	data := nestedSearchData(result, "article")
	return map[string]any{
		"id":            firstMapValue(data, "id"),
		"title":         firstMapValue(data, "title"),
		"locale":        firstMapValue(data, "locale"),
		"content":       firstMapValue(data, "content"),
		"slug":          firstMapValue(data, "slug"),
		"portal_slug":   firstMapValue(data, "portal_slug"),
		"account_id":    firstMapValue(data, "account_id"),
		"category_name": firstMapValue(data, "category_name"),
		"status":        firstMapValue(data, "status"),
		"updated_at":    unixFromMapValue(firstMapValue(data, "updated_at", "updated_at_ts")),
	}
}

func serializeSearchArticleModel(article *model.Article) map[string]any {
	portalSlug := ""
	if article.Portal.Slug != "" {
		portalSlug = article.Portal.Slug
	}
	categoryName := ""
	if article.Category != nil && article.Category.Name != "" {
		categoryName = article.Category.Name
	}
	return map[string]any{
		"id":            article.ID,
		"title":         article.Title,
		"locale":        article.Locale,
		"content":       article.Content,
		"slug":          article.Slug,
		"portal_slug":   portalSlug,
		"account_id":    article.AccountID,
		"category_name": categoryName,
		"status":        article.Status,
		"updated_at":    article.UpdatedAt.Unix(),
	}
}

func nestedSearchData(result search.SearchResult, key string) map[string]any {
	root, ok := anyMap(result.Data)
	if !ok {
		return map[string]any{}
	}
	if nested, ok := anyMap(root[key]); ok {
		return nested
	}
	if data, ok := anyMap(root["data"]); ok {
		if nested, ok := anyMap(data[key]); ok {
			return nested
		}
		return data
	}
	return root
}

func anyMap(value any) (map[string]any, bool) {
	switch typed := value.(type) {
	case map[string]any:
		return typed, true
	case gin.H:
		return map[string]any(typed), true
	default:
		return nil, false
	}
}

func firstMapValue(data map[string]any, keys ...string) any {
	for _, key := range keys {
		if value, ok := data[key]; ok {
			return value
		}
	}
	return nil
}

func unixFromMapValue(value any) any {
	switch typed := value.(type) {
	case float64:
		return int64(typed)
	case int64:
		return typed
	case int:
		return int64(typed)
	case uint:
		return int64(typed)
	default:
		return typed
	}
}