portfolio-tracker/internal/handler/api.go

package handler

import (
	"encoding/json"
	"fmt"
	"net/http"
	"portfolio-tracker/internal/model"
	"portfolio-tracker/internal/util"
	"time"
)

func JsonEndpoint(w http.ResponseWriter, r *http.Request) {
	stock := r.URL.Query().Get("stock")

	// Standardwerte setzen, falls Parameter fehlen
	if stock == "" {
		stock = "IDIA.SW"
	}

	data, err := util.FetchYahooFinanceData(stock)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}
	w.Header().Set("Content-Type", "application/json")
	w.Write([]byte(data))
}

func YahooMaxDividendsHandler(w http.ResponseWriter, r *http.Request) {
	stock := r.URL.Query().Get("stock")
	if stock == "" {
		http.Error(w, "Fehlender stock-Parameter", http.StatusBadRequest)
		return
	}

	data, err := util.FetchYahooFinanceDataMax(stock)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	var resp model.YahooDividendChartResponse
	err = json.Unmarshal([]byte(data), &resp)
	if err != nil {
		http.Error(w, "Fehler beim Parsen der Yahoo-Dividenden-Daten: "+err.Error(), http.StatusInternalServerError)
		return
	}

	var result [][]interface{}
	if len(resp.Chart.Result) > 0 {
		for _, div := range resp.Chart.Result[0].Events.Dividends {
			result = append(result, []interface{}{div.Date * 1000, div.Amount})
		}
	}

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

func StockSearchEndpoint(w http.ResponseWriter, r *http.Request) {
	query := r.URL.Query().Get("q")
	if query == "" {
		http.Error(w, "Fehlender q-Parameter", http.StatusBadRequest)
		return
	}

	data, err := util.StockSearch(query)
	if err != nil {
		http.Error(w, err.Error(), http.StatusInternalServerError)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	w.Write([]byte(data))
}

// Helper function to get stock currency from Yahoo Finance
func getStockCurrency(stock string) (string, error) {
	// Fetch basic stock data from Yahoo Finance
	data, err := util.FetchYahooFinanceData(stock)
	if err != nil {
		return "", err
	}

	// Parse the JSON response
	var resp util.YahooChartResponse
	err = json.Unmarshal([]byte(data), &resp)
	if err != nil {
		return "", err
	}

	// Extract currency from the response
	if len(resp.Chart.Result) > 0 {
		currency := resp.Chart.Result[0].Meta.Currency
		if currency != "" {
			return currency, nil
		}
	}

	return "", fmt.Errorf("currency not found in response")
}

// ClearCurrencyCacheHandler clears the currency conversion cache
func ClearCurrencyCacheHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "Nur POST erlaubt", http.StatusMethodNotAllowed)
		return
	}

	util.ClearCache()

	response := map[string]string{
		"status":  "success",
		"message": "Currency cache (including historical rates) cleared successfully",
	}

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

// CleanExpiredCacheHandler removes expired cache entries
func CleanExpiredCacheHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodPost {
		http.Error(w, "Nur POST erlaubt", http.StatusMethodNotAllowed)
		return
	}

	removedCount := util.CleanExpiredCache()

	response := map[string]interface{}{
		"status":        "success",
		"message":       "Expired cache entries cleaned",
		"removed_count": removedCount,
	}

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

// CurrencyCacheInfoHandler returns information about the currency cache
func CurrencyCacheInfoHandler(w http.ResponseWriter, r *http.Request) {
	if r.Method != http.MethodGet {
		http.Error(w, "Nur GET erlaubt", http.StatusMethodNotAllowed)
		return
	}

	detailedCacheInfo := util.GetDetailedCacheInfo()

	// Separate historical and current rates
	historicalRates := make(map[string]interface{})
	currentRates := make(map[string]interface{})

	for key, cached := range detailedCacheInfo {
		rateInfo := map[string]interface{}{
			"rate":      cached.Rate,
			"timestamp": cached.Timestamp,
			"date":      cached.Date,
			"age_hours": time.Since(cached.Timestamp).Hours(),
		}

		if cached.Date == cached.Timestamp.Format("2006-01-02") {
			currentRates[key] = rateInfo
		} else {
			historicalRates[key] = rateInfo
		}
	}

	response := map[string]interface{}{
		"status":           "success",
		"total_entries":    len(detailedCacheInfo),
		"historical_rates": historicalRates,
		"current_rates":    currentRates,
		"historical_count": len(historicalRates),
		"current_count":    len(currentRates),
	}

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