package main

import (
	"net/http"
	"strings"
	"time"
)

type ChatSearchResult struct {
	ConversationID    string    `json:"conversationId"`
	MessageID         string    `json:"messageId"`
	Body              string    `json:"body"`
	SenderDisplayName string    `json:"senderDisplayName"`
	CreatedAt         time.Time `json:"createdAt"`
}

func (s *Server) handleSearchChatMessages(w http.ResponseWriter, r *http.Request) {
	user, ok := userFromContext(r.Context())
	if !ok {
		writeError(w, http.StatusUnauthorized, "Unauthorized")
		return
	}

	query := strings.TrimSpace(r.URL.Query().Get("q"))
	if query == "" {
		writeJSON(w, http.StatusOK, map[string]any{
			"results": []ChatSearchResult{},
		})
		return
	}

	rows, err := s.db.Query(
		r.Context(),
		`
		SELECT DISTINCT ON (m.conversation_id)
			m.conversation_id::TEXT,
			m.id::TEXT,
			m.body,
			COALESCE(
				NULLIF(u.display_name, ''),
				NULLIF(u.username, ''),
				u.email,
				NULLIF(c.channel_source_name, ''),
				c.name,
				''
			),
			m.created_at
		FROM messages m
		JOIN conversations c ON c.id = m.conversation_id
		LEFT JOIN users u ON u.id = m.sender_id
		WHERE m.deleted_at IS NULL
		  AND m.message_type = 'user'
		  AND (m.expires_at IS NULL OR m.expires_at > now())
		  AND strpos(lower(m.body), lower($2)) > 0
		  AND EXISTS (
			SELECT 1
			FROM conversation_members cm
			WHERE cm.conversation_id = c.id
			  AND cm.user_id = $1
		  )
		ORDER BY m.conversation_id, m.created_at DESC, m.id DESC
		LIMIT 50
		`,
		user.ID,
		query,
	)
	if err != nil {
		writeError(w, http.StatusInternalServerError, "Chatnachrichten konnten nicht durchsucht werden")
		return
	}
	defer rows.Close()

	results := []ChatSearchResult{}
	for rows.Next() {
		var result ChatSearchResult
		if err := rows.Scan(
			&result.ConversationID,
			&result.MessageID,
			&result.Body,
			&result.SenderDisplayName,
			&result.CreatedAt,
		); err != nil {
			writeError(w, http.StatusInternalServerError, "Suchergebnisse konnten nicht gelesen werden")
			return
		}
		results = append(results, result)
	}

	if err := rows.Err(); err != nil {
		writeError(w, http.StatusInternalServerError, "Suchergebnisse konnten nicht vollständig geladen werden")
		return
	}

	writeJSON(w, http.StatusOK, map[string]any{
		"results": results,
	})
}