package main

import (
	"context"
	"flag"
	"fmt"
	"log"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"resume-builder/internal/api"
	"resume-builder/internal/db"
	"resume-builder/internal/llm"
	"resume-builder/internal/rag"
)

func main() {
	addr := flag.String("addr", ":8080", "HTTP listen address")
	dbPath := flag.String("db", "./data/resume.db", "SQLite database path")
	llmBaseURL := flag.String("llm-base", os.Getenv("LLM_BASE_URL"), "LLM API base URL (OpenAI compatible)")
	llmModel := flag.String("llm-model", os.Getenv("LLM_MODEL"), "LLM model name")
	llmKey := flag.String("llm-key", os.Getenv("LLM_API_KEY"), "LLM API key")
	flag.Parse()

	if *llmBaseURL == "" {
		*llmBaseURL = "http://localhost:11434"
	}
	if *llmModel == "" {
		*llmModel = "llama3"
	}
	if *llmKey == "" {
		*llmKey = "not-needed"
	}

	fmt.Printf("Resume Builder\n")
	fmt.Printf("  LLM: %s (model: %s)\n", *llmBaseURL, *llmModel)
	fmt.Printf("  Database: %s\n", *dbPath)
	fmt.Printf("  Server: http://localhost%s\n", *addr)
	fmt.Println()

	// Initialize database
	database, err := db.New(*dbPath)
	if err != nil {
		log.Fatalf("Failed to initialize database: %v", err)
	}
	defer database.Close()

	// Initialize LLM client
	llmClient := llm.New(*llmBaseURL, *llmKey, *llmModel)

	// Initialize RAG service
	ragService := rag.New(database, llmClient)

	// Setup API handlers
	handler := api.New(database, ragService)

	// Create router
	mux := http.NewServeMux()
	handler.SetupRoutes(mux)

	// Wrap with CORS
	corsHandler := api.CorsMiddleware(mux)

	// Start server
	server := &http.Server{
		Addr:    *addr,
		Handler: corsHandler,
	}

	// Graceful shutdown
	sig := make(chan os.Signal, 1)
	signal.Notify(sig, syscall.SIGINT, syscall.SIGTERM)

	go func() {
		<-sig
		log.Println("\nShutting down server...")
		ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
		defer cancel()
		if err := server.Shutdown(ctx); err != nil {
			log.Printf("Server shutdown error: %v", err)
		}
	}()

	log.Printf("Server listening on %s", *addr)
	if err := server.ListenAndServe(); err != nil && err != http.ErrServerClosed {
		log.Fatalf("Server error: %v", err)
	}
}