package rest

import (
	"context"
	"encoding/json"
	"net/http"
	"time"
)

// handleStats handles GET /api/v2/stats
func (s *Server) handleStats(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		writeMethodNotAllowed(w)
		return
	}
	if !s.requireDB(w) {
		return
	}

	ctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer cancel()

	// Get total blocks
	var totalBlocks int64
	err := s.db.QueryRow(ctx,
		`SELECT COUNT(*) FROM blocks WHERE chain_id = $1`,
		s.chainID,
	).Scan(&totalBlocks)
	if err != nil {
		totalBlocks = 0
	}

	// Get total transactions
	var totalTransactions int64
	err = s.db.QueryRow(ctx,
		`SELECT COUNT(*) FROM transactions WHERE chain_id = $1`,
		s.chainID,
	).Scan(&totalTransactions)
	if err != nil {
		totalTransactions = 0
	}

	// Get total addresses
	var totalAddresses int64
	err = s.db.QueryRow(ctx,
		`SELECT COUNT(DISTINCT from_address) + COUNT(DISTINCT to_address) FROM transactions WHERE chain_id = $1`,
		s.chainID,
	).Scan(&totalAddresses)
	if err != nil {
		totalAddresses = 0
	}

	stats := map[string]interface{}{
		"total_blocks":       totalBlocks,
		"total_transactions": totalTransactions,
		"total_addresses":    totalAddresses,
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(stats)
}