package main

import (
	"context"
	"embed"
	"flag"
	"fmt"
	"io/fs"
	"log"
	"net/http"
	"os"
	"os/signal"
	"path/filepath"
	"syscall"

	"fn-registry/functions/infra"
)

//go:embed all:frontend/dist
var frontendDist embed.FS

func main() {
	flags := flag.NewFlagSet("kanban", flag.ExitOnError)
	port := flags.Int("port", 8095, "HTTP port")
	dbPath := flags.String("db", "operations.db", "SQLite database path")
	flags.Parse(os.Args[1:])

	db, err := openDB(*dbPath)
	if err != nil {
		log.Fatalf("open db: %v", err)
	}
	defer db.Close()

	wd := chatWorkdir(*dbPath)
	logger := newChatLogger(filepath.Join(wd, "chat.log"))
	log.Printf("chat tool log: %s", logger.path)
	mux := infra.HTTPRouter(apiRoutes(db, wd, logger))

	feHandler := frontendHandler()
	if feHandler != nil {
		mux.Handle("/", feHandler)
		log.Printf("serving frontend from embedded dist/")
	} else {
		log.Printf("no frontend build found, API-only mode")
	}

	chain := infra.HTTPMiddlewareChain(
		infra.HTTPLoggerMiddleware(os.Stdout),
		infra.HTTPCORSMiddleware([]string{"*"}, []string{"GET", "POST", "PATCH", "DELETE", "OPTIONS"}),
	)
	handler := chain(mux)

	addr := fmt.Sprintf(":%d", *port)
	log.Printf("kanban server starting on http://0.0.0.0%s", addr)
	log.Printf("database: %s", *dbPath)

	ctx, cancel := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
	defer cancel()

	if err := infra.HTTPServe(addr, handler, ctx); err != nil {
		log.Fatalf("server: %v", err)
	}
}

func frontendHandler() http.Handler {
	sub, err := fs.Sub(frontendDist, "frontend/dist")
	if err != nil {
		return nil
	}
	entries, _ := fs.ReadDir(sub, ".")
	if len(entries) == 0 {
		return nil
	}
	return infra.SPAHandler(sub, "index.html")
}