package main

import (
	"flag"
	"log"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"time"

	"chfs-ng/internal/api"
	"chfs-ng/internal/auth"
	"chfs-ng/internal/config"
	"chfs-ng/internal/opslog"
	"chfs-ng/internal/storage"
)

func main() {
	file := flag.String("file", "", "configuration file")
	pathFlag := flag.String("path", "/data", "shared path")
	port := flag.Int("port", 80, "listen port")
	allow := flag.String("allow", "", "allowed IPv4 addresses")
	var rules multiFlag
	flag.Var(&rules, "rule", "access rule (repeatable)")
	flag.Parse()

	cfg := config.Default()
	if *file != "" {
		loaded, err := config.Load(*file)
		if err != nil && !os.IsNotExist(err) {
			log.Fatal(err)
		}
		if err == nil {
			cfg = loaded
		}
	}
	flag.CommandLine.Visit(func(f *flag.Flag) {
		switch f.Name {
		case "path":
			cfg.Path = splitPath(*pathFlag)
		case "port":
			cfg.Port = *port
		case "allow":
			cfg.Allow = *allow
		case "rule":
			cfg.Rules = append([]string(nil), rules...)
		}
	})
	if len(cfg.Path) == 0 {
		cfg.Path = []string{"/data"}
	}
	if err := cfg.Validate(); err != nil {
		log.Fatal(err)
	}

	root := cfg.Path[0]
	for _, p := range cfg.Path {
		if err := os.MkdirAll(p, 0755); err != nil {
			log.Fatal(err)
		}
	}
	mgr, err := auth.ParseRules(cfg.Rules)
	if err != nil {
		log.Fatal(err)
	}
	for _, ac := range cfg.Accounts {
		a := &auth.Account{Username: ac.Username, Password: ac.Password, Mask: auth.ParseMask(ac.Default)}
		for _, d := range ac.None {
			a.Rules = append(a.Rules, auth.PathRule{Dir: d, Deny: true})
		}
		for _, d := range ac.Read {
			a.Rules = append(a.Rules, auth.PathRule{Dir: d, Mask: auth.Read, ChildrenOnly: true})
		}
		for _, d := range ac.Write {
			a.Rules = append(a.Rules, auth.PathRule{Dir: d, Mask: auth.ParseMask("w"), ChildrenOnly: true})
		}
		for _, d := range ac.Delete {
			a.Rules = append(a.Rules, auth.PathRule{Dir: d, Mask: auth.ParseMask("d"), ChildrenOnly: true})
		}
		if ac.Username == "guest" {
			mgr.Guest = a
		} else {
			mgr.Accounts[ac.Username] = a
		}
	}
	multi := storage.NewMulti(cfg.Path)
	store := storage.Storage(multi)
	if len(cfg.Path) == 1 {
		store = storage.Local{Root: root}
	}
	srv := &api.Server{Store: store, Auth: mgr, Sessions: map[string]*auth.Account{}, SessionExpiry: map[string]time.Time{}, SessionTimeout: cfg.SessionTimeout, WebDAVRoot: root, Allow: cfg.Allow, MultiRoot: len(cfg.Path) > 1, RemoveMode: cfg.FileRemove, ImagePreview: cfg.ImagePreview, Log: opslog.New(cfg.Log)}
	addr := ":" + itoa(cfg.Port)
	log.Printf("chfs-ng listening on %s root=%s removeMode=%d", addr, filepath.Clean(root), cfg.FileRemove)
	if cfg.SSLCert != "" && cfg.SSLKey != "" {
		log.Fatal(http.ListenAndServeTLS(addr, cfg.SSLCert, cfg.SSLKey, srv.Handler()))
	}
	log.Fatal(http.ListenAndServe(addr, srv.Handler()))
}

type multiFlag []string

func (m *multiFlag) String() string     { return strings.Join(*m, "|") }
func (m *multiFlag) Set(v string) error { *m = append(*m, v); return nil }

func itoa(n int) string {
	const d = "0123456789"
	if n == 0 {
		return "0"
	}
	b := make([]byte, 0, 6)
	for n > 0 {
		b = append([]byte{d[n%10]}, b...)
		n /= 10
	}
	return string(b)
}

func splitPath(v string) []string {
	var out []string
	for _, p := range strings.Split(v, "|") {
		p = strings.TrimSpace(p)
		if p != "" {
			out = append(out, p)
		}
	}
	return out
}