// Command byteclaw runs the ByteClaw assistant server.
package main

import (
	"context"
	"errors"
	"flag"
	"fmt"
	"log/slog"
	"net/http"
	"os"
	"os/signal"
	"path/filepath"
	"syscall"
	"time"

	"github.com/crypto/byteclaw/internal/agent"
	"github.com/crypto/byteclaw/internal/config"
	"github.com/crypto/byteclaw/internal/llm"
	"github.com/crypto/byteclaw/internal/server"
	"github.com/crypto/byteclaw/internal/store"
	"github.com/crypto/byteclaw/internal/tools"
)

var version = "dev"

func main() {
	cfgPath := flag.String("config", os.Getenv("BYTECLAW_CONFIG"), "path to config file (.yaml/.yml/.json)")
	showVersion := flag.Bool("version", false, "print version")
	flag.Parse()
	if *showVersion {
		fmt.Println("byteclaw", version)
		return
	}
	log := slog.New(slog.NewTextHandler(os.Stderr, nil))
	if err := run(*cfgPath, log); err != nil {
		log.Error("fatal", "err", err)
		os.Exit(1)
	}
}

func run(cfgPath string, log *slog.Logger) error {
	cfg, err := config.Load(cfgPath)
	if err != nil {
		return err
	}
	if err := os.MkdirAll(cfg.DataDir, 0o750); err != nil {
		return err
	}
	st, err := store.Open(filepath.Join(cfg.DataDir, "byteclaw.db"))
	if err != nil {
		return err
	}
	defer st.Close()

	reg := tools.NewRegistry(tools.TimeNow{})
	if cfg.Tools.WebFetch.Enabled {
		reg.Register(tools.NewWebFetch(time.Duration(cfg.Tools.WebFetch.TimeoutSec)*time.Second, cfg.Tools.WebFetch.MaxBytes, cfg.Tools.WebFetch.AllowPrivate))
	}
	if cfg.Tools.FilesEnabled {
		ws := tools.Workspace{Dir: cfg.Workspace, MaxBytes: cfg.Tools.FileMaxBytes}
		reg.Register(tools.FileRead{Workspace: ws})
		reg.Register(tools.FileWrite{Workspace: ws})
		reg.Register(tools.FileList{Workspace: ws})
	}
	prov := llm.NewOpenAI(cfg.LLM.BaseURL, cfg.LLM.APIKey, cfg.LLM.Model, cfg.LLM.Temperature, time.Duration(cfg.LLM.TimeoutSec)*time.Second)
	ag := &agent.Agent{LLM: prov, Tools: reg, Store: st, SystemPrompt: cfg.Agent.SystemPrompt,
		MaxIterations: cfg.Agent.MaxIterations, HistoryLimit: cfg.Agent.HistoryLimit}
	srv := &server.Server{Agent: ag, Store: st, Token: cfg.AuthToken, AllowedOrigins: cfg.AllowedOrigins, Log: log,
		RunTimeout: time.Duration(cfg.LLM.TimeoutSec*cfg.Agent.MaxIterations) * time.Second}

	hs := &http.Server{Addr: cfg.Listen, Handler: srv.Handler(), ReadHeaderTimeout: 10 * time.Second, IdleTimeout: 120 * time.Second}
	ctx, stop := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer stop()
	errc := make(chan error, 1)
	go func() {
		log.Info("byteclaw listening", "addr", cfg.Listen, "model", cfg.LLM.Model, "tools", len(reg.Specs()), "version", version)
		errc <- hs.ListenAndServe()
	}()
	select {
	case err := <-errc:
		if !errors.Is(err, http.ErrServerClosed) {
			return err
		}
	case <-ctx.Done():
		log.Info("shutting down")
		sctx, cancel := context.WithTimeout(context.Background(), 10*time.Second)
		defer cancel()
		return hs.Shutdown(sctx)
	}
	return nil
}