package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"log"
	"net/http"
	"strconv"
)

func main() {
	port := flag.Int("port", 8085, "port to listen on")
	capacity := flag.Int("capacity", 1000000, "max messages to store")

	flag.Parse()

	store := NewLogStore(*capacity)

	http.HandleFunc("POST /log", func(w http.ResponseWriter, r *http.Request) {
		var msg Message
		if err := json.NewDecoder(r.Body).Decode(&msg); err != nil {
			http.Error(w, "invalid JSON", http.StatusBadRequest)
			return
		}

		store.Add(msg)
		w.WriteHeader(http.StatusCreated)
	})

	http.HandleFunc("GET /logs", func(w http.ResponseWriter, r *http.Request) {
		params := FilterParams{}

		if limit := r.URL.Query().Get("limit"); limit != "" {
			if n, err := strconv.Atoi(limit); err == nil {
				params.Limit = n
			}
		}
		if before := r.URL.Query().Get("before"); before != "" {
			if ts, err := strconv.ParseInt(before, 10, 64); err == nil {
				params.Before = ts
			}
		}
		if after := r.URL.Query().Get("after"); after != "" {
			if ts, err := strconv.ParseInt(after, 10, 64); err == nil {
				params.After = ts
			}
		}

		messages := store.GetFiltered(params)

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

	http.HandleFunc("GET /status", func(w http.ResponseWriter, r *http.Request) {
		status := map[string]any{
			"count":    store.Count(),
			"capacity": *capacity,
		}
		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(status)
	})

	listenAddr := fmt.Sprintf(":%d", *port)
	log.Printf("[logger] Listening on %s (capacity: %d)", listenAddr, *capacity)
	if err := http.ListenAndServe(listenAddr, nil); err != nil {
		log.Fatalf("[logger] Failed to start: %v", err)
	}
}