#include <u.h>
#include <libc.h>
#include <fcall.h>
#include <thread.h>
#include <9p.h>
#include <stdio.h>
#include <dirent.h>
#include <libString.h>
#include <string.h>
#include "config.h"
#include "err.h"
#include "command.h"
#include "util.h"
#include "aux.h"
#include "cart.h"
#include "universe.h"
#include "realm.h"
#include "user.h"

char version[] = "0.3";

int chatty9p = 0;

static Tree* tree;

static UserInfo users_table[MAX_USERS];

void helpme(char* arg0) {
  printf("usage: %s [-m MOUNTPOINT | -s SOCKET | -v | -h|--help]\n", arg0);
  printf("Serve xrxs game infrastructure over 9p.\n\n");

  printf("  -m MOUNTPOINT: mount the 9p filesystem locally at MOUNTPOINT\n");
  printf("  -s SOCKET: create a socket for the 9p filesystem with the "
         "namespace SOCKET\n");
  printf("  -v: print version information\n");
  printf("  -h | --help: print this help text\n\n");
  threadexits(0);
}

void xrxs_attach(Req* r) {
  /* As it is, once the user detaches, they will stay in the table
   * until the server restarts. We have to figure out some way
   * to detect a detach to remove them... You can't delay respond()
   * or the attach will never complete. We have logout() for now...
   */
  int i = 0;
  int vacancy = 0;
  char* usr;
  char* username = r->ifcall.uname;

  for (i = 0; i < MAX_USERS; i++) {
    usr = users_table[i].name;
    if (scmp(usr, username)) {
      respond(r, EUNAME);
      return;
    }
    if (*usr == 0) {
      scpy(username, usr, 32);
      users_table[i].random = -1;
      vacancy = 1;
      break;
    }
  }
  if (vacancy) {
    respond(r, nil);
  } else {
    respond(r, EUFULL);
  }
}

void write_ctl(Req* r) {
  char cmd[16] = {0};
  char* c = r->ifcall.data;
  int i;
  int* code = ctl_code_handle(users_table, r->fid->uid);

  for (i = 0; i < r->ifcall.count && *c != ' ' && *c != '\n'; i++) {
    ccat(cmd, *c++);
  }
  if (*c == ' ')
    c++;
  scsw(c, '\n', 0);

  fprintf(stderr, "%s(%s)\n", cmd, c);
  uvlong const cmd_hashv = hash(cmd, 0);
  switch (cmd_hashv) {
    case LOGIN:
      *code = login(users_table, r->fid->uid, c);
      break;
    case LOAD:
      *code = load_cart(users_table, r->fid->uid, c);
      break;
    case CHUNK:
      *code = get_chunk(users_table, r->fid->uid, c);
      break;
    case CREATE:
      *code = create_realm(users_table, r->fid->uid, c) != nil ? 1 : 0;
      break;
    case PROTECT:
      *code = protect_realm(users_table, r->fid->uid, c);
      break;
    case TRANSFER:
      *code = transfer_realm(users_table, r->fid->uid, c);
      break;
    case DELETE:
      *code = delete_realm(users_table, r->fid->uid, c);
      break;
    case ENTER:
      *code = enter_realm(users_table, r->fid->uid, c);
      break;
    case LEAVE:
      *code = leave_realm(users_table, r->fid->uid);
      break;
    case LOGOUT:
      logout(users_table, r->fid->uid);
      break;
    case SAVE:
      // save(r->fid->uid);
      break;
    case RESET:
      // reset(r->fid->uid);
      break;
    case UNLOAD:
      *code = unload_cart(users_table, r->fid->uid);
      break;
  }
  r->ofcall.count = r->ifcall.count;
  r->fid->file->dir.length = r->ifcall.count;
  respond(r, nil);
}

void write_universe(Req* r) {
  char key[16] = {0};
  char value[64] = {0};
  char buffer[1024] = {0};
  UserInfo* u = find_user(users_table, r->fid->uid);
  Atom* a;

  scpy(r->ifcall.data, buffer, r->ifcall.count);
  sscanf(buffer, "%15s = %63s", key, value);

  /*  for (i = 0; i < 15 && i < r->ifcall.count && *c != ' ' && *c != '\n'; i++)
    { ccat(key, *c++);
    }
    c++;
    c++;
    for (i = 0; i < 63 && i < r->ifcall.count && *c != ' ' && *c != '\n'; i++) {
      ccat(value, *c++);
    }
  */
  if (u != nil && u->realm != nil && u->realm->universe != nil) {
    a = get_atom(u->realm->universe, key);
    if (a != nil) {
      scpy(value, a->value, 64);
    } else {
      a = malloc(sizeof(Atom));
      scpy(key, a->name, 16);
      scpy(value, a->value, 64);
      a->next = nil;
      set_atom(u->realm->universe, a);
    }
  }
  r->ofcall.count = r->ifcall.count;
  r->fid->file->dir.length = r->ifcall.count;
  respond(r, nil);
}

void write_scope(Req* r) {
  String* scope = s_new();
  char* c = r->ifcall.data;
  UserInfo* u = find_user(users_table, r->fid->uid);
  int i;

  for (i = 0; i < r->ifcall.count; i++) {
    s_putc(scope, *c++);
  }
  s_terminate(scope);
  fprintf(stderr, scope->base);

  if (u != nil && u->realm != nil && u->realm->universe != nil) {
    u->scope = malloc(r->ifcall.count);
    memcpy(u->scope, scope->base, r->ifcall.count);
  }
  s_free(scope);
  r->ofcall.count = r->ifcall.count;
  r->fid->file->dir.length = r->ifcall.count;
  respond(r, nil);
}

void xrxs_write(Req* r) {
  Aux* a = r->fid->file->aux;
  switch (a->type) {
    case CTL:
      write_ctl(r);
      break;
    case UNIVERSE:
      write_universe(r);
      break;
    case SCOPE:
      write_scope(r);
      break;
    default:
      respond(r, nil);
      break;
  }
}

void read_users(Req* r) {
  String* data = s_new();
  int i;
  for (i = 0; i < MAX_USERS; i++) {
    if (scmp(users_table[i].name, r->fid->uid)) {
      s_append(data, users_table[i].name);
      s_putc(data, '\n');
      break;
    }
  }
  for (i = 0; i < MAX_USERS; i++) {
    if (
      scmp(users_table[i].name, "\0") ||
      scmp(users_table[i].name, r->fid->uid)) {
      continue;
    }
    s_append(data, users_table[i].name);
    s_putc(data, '\n');
  }
  s_terminate(data);
  readstr(r, data->base);
  s_free(data);
  respond(r, nil);
}

String** list_dir(char* path) {
  int size = 128;
  String** self = malloc(size * sizeof(String*));
  DIR* dir;
  struct dirent* ent;
  int i = 0;
  char* c;
  if ((dir = opendir(path)) != NULL) {
    while ((ent = readdir(dir)) != NULL) {
      if (i == size) {
        size *= 2;
        self = realloc(self, size * sizeof(String*));
      }
      c = ent->d_name;
      if (scmp(c, ".") || scmp(c, "..")) {
        continue;
      }
      self[i] = s_new();

      while (*c) {
        s_putc(self[i], *c++);
      }
      s_terminate(self[i++]);
    }
    closedir(dir);
  }
  self[i] = nil;
  return self;
}

void s_freemany(String** ss) {
  String** s = ss;
  while (*s != nil) {
    s_free(*s++);
  }
  free(ss);
}

void read_ctl(Req* r) {
  int* code = ctl_code_handle(users_table, r->fid->uid);
  char buf[8] = {0};
  if (code != nil) {
    if (*code) {
      strcat(buf, "1\n");
    } else {
      strcat(buf, "0\n");
    }
  } else {
    strcat(buf, "-1\n");
  }
  readstr(r, buf);
  respond(r, nil);
}

void read_carts(Req* r) {
  String** carts = list_dir(DATA_DIR);
  String** c = carts;
  String* data = s_new();
  while (*c != nil) {
    s_append(data, (*c)->base);
    s_putc(data, '\n');
    c++;
  }
  s_terminate(data);
  readstr(r, data->base);
  respond(r, nil);
  s_free(data);
  s_freemany(carts);
}

void read_slot(Req* r) {
  UserInfo* u = find_user(users_table, r->fid->uid);
  if (u == nil)
    goto end;

  if (u->cart == nil)
    goto end;

  readbuf(r, u->cart->rom->data, u->cart->rom->length);
end:
  respond(r, nil);
}

void read_data(Req* r, FileType t) {
  UserInfo* u = find_user(users_table, r->fid->uid);
  vlong offset = r->ifcall.offset;
  long count = r->ifcall.count;

  if (u->cart == nil)
    goto end;

  switch (t) {
    case SPRITE_DATA:
      if (
        u->cart->sprite_data != nil && offset < u->cart->sprite_data->length) {
        if (offset + count >= u->cart->sprite_data->length)
          count = u->cart->sprite_data->length - offset;
        readbuf(r, u->cart->sprite_data->data + offset, count);
      }
      break;
    case AUDIO_DATA:
      if (u->cart->audio_data != nil && offset < u->cart->audio_data->length) {
        if (offset + count >= u->cart->audio_data->length)
          count = u->cart->audio_data->length - offset;
        readbuf(r, u->cart->audio_data->data + offset, count);
      }
      break;
    case TEXT_DATA:
      if (u->cart->txt_data != nil && offset < u->cart->txt_data->length) {
        if (offset + count >= u->cart->txt_data->length)
          count = u->cart->txt_data->length - offset;
        readbuf(r, u->cart->txt_data->data + offset, count);
      }
      break;
  }
end:
  r->ofcall.count = count;
  respond(r, nil);
}

void read_realms(Req* r) {
  UserInfo* user = find_user(users_table, r->fid->uid);
  char realm_path[256] = {0};
  String** realms;
  String** rr;
  Realm* realm;
  String* data = s_new();
  int i, u, m, p;
  char ubuf[8] = {0};
  char mbuf[8] = {0};
  char pbuf[2] = {0};

  if (user->cart == nil)
    respond(r, nil);

  scat(realm_path, DATA_DIR);
  scat(realm_path, user->cart->name);
  scat(realm_path, "/realms");

  realms = list_dir(realm_path);
  rr = realms;

  while (*rr != nil) {
    s_append(data, (*rr)->base);
    s_putc(data, ' ');

    realm = parse_realm(user->cart->name, (*rr)->base);
    m = realm->max;
    p = realm->password ? 1 : 0;

    for (i = u = 0; i < MAX_USERS; i++) {
      if (
        users_table[i].realm != nil &&
        scmp(users_table[i].realm->name, realm->name))
        u++;
    }
    itoa(u, ubuf, 10);
    s_append(data, ubuf);
    s_putc(data, ' ');
    itoa(m, mbuf, 10);
    s_append(data, mbuf);
    s_putc(data, ' ');
    itoa(p, pbuf, 10);
    s_append(data, pbuf);
    s_putc(data, '\n');
    rr++;
  }
  s_terminate(data);
  readstr(r, data->base);
  respond(r, nil);
  s_free(data);
  s_freemany(realms);
}

void read_universe(Req* r) {
  char* uname = r->fid->uid;
  UserInfo* u = find_user(users_table, uname);
  String* data = s_new();
  Universe* universe;
  Atom* a;
  int i;

  if (u == nil || u->realm == nil) {
    fprintf(stderr, "realm nil, wtf\n");
    respond(r, nil);
    return;
  }

  universe = u->realm->universe;
  if (universe == nil) {
    fprintf(stderr, "no universe, oh noes!!\n");
    respond(r, ENOUNI);
    return;
  }

  for (i = 0; i < 256; i++) {
    a = universe->atoms[i];
    while (a != nil) {
      s_append(data, a->name);
      s_append(data, " = ");
      s_append(data, a->value);
      s_putc(data, '\n');
      a = a->next;
    }
  }
  s_terminate(data);
  readstr(r, data->base);
  respond(r, nil);
  s_free(data);
}

void read_scope(Req* r) {
  char* uname = r->fid->uid;
  UserInfo* u = find_user(users_table, uname);
  String* data = s_new();
  Universe* universe;
  Atom* a;
  char key[16] = {0};
  char* c;

  if (u == nil || u->scope == nil || u->realm == nil) {
    respond(r, nil);
    return;
  }

  c = u->scope;
  universe = u->realm->universe;
  if (universe == nil) {
    respond(r, ENOUNI);
    return;
  }

  while (*c) {
    while (*c != '\n') {
      ccat(key, *c++);
    }
    a = get_atom(universe, key);
    if (a != nil) {
      s_append(data, a->value);
      s_putc(data, '\n');
    }
    *key = '\0';
    if (*c == '\0')
      break;
    c++;
  }

  s_terminate(data);
  readstr(r, data->base);
  respond(r, nil);
  s_free(data);
}

void read_random(Req* r) {
  char buf[8] = {0};
  srand(rand());
  sprintf(buf, "%d\n", rand() % 100);
  readstr(r, buf);
  respond(r, nil);
}

void read_grandom(Req* r) {
  char buf[8] = {0};
  int i;
  int reset = 1;
  int random;
  UserInfo* u = find_user(users_table, r->fid->uid);
  UserInfo** usrs = malloc(MAX_USERS * sizeof(UserInfo*));
  UserInfo* p = users_table;
  UserInfo** uu = usrs;

  if (u->realm == nil) {
    respond(r, nil);
    return;
  }

  for (i = 0; i < MAX_USERS; i++) {
    if (scmp(p->realm->name, u->realm->name)) {
      *uu++ = p;
      if (i < MAX_USERS - 1)
        *uu = nil;
    }
  }
  uu = usrs;
  for (i = 0; i < MAX_USERS; i++) {
    if ((*uu) != nil && (*uu)->random >= 0) {
      reset = 0;
      break;
    }
    uu++;
  }
  if (reset) {
    srand(rand());
    random = rand() % 100;
    uu = usrs;
    for (i = 0; i < MAX_USERS; i++) {
      if ((*uu) != nil) {
        (*uu)->random = random;
      }
      uu++;
    }
  }
  sprintf(buf, "%d\n", u->random);
  u->random = -1;
  readstr(r, buf);
  respond(r, nil);
}

void read_version(Req* r) {
  char buf[16];
  sprintf(buf, "%s\n", version);
  readstr(r, buf);
  respond(r, nil);
}

void xrxs_read(Req* r) {
  Aux* a = r->fid->file->aux;
  switch (a->type) {
    case CTL:
      read_ctl(r);
      break;
    case USERS:
      read_users(r);
      break;
    case CARTS:
      read_carts(r);
      break;
    case SLOT:
      read_slot(r);
      break;
    case SPRITE_DATA:
    case AUDIO_DATA:
    case TEXT_DATA:
      read_data(r, a->type);
      break;
    case REALMS:
      read_realms(r);
      break;
    case UNIVERSE:
      read_universe(r);
      break;
    case SCOPE:
      read_scope(r);
      break;
    case RANDOM:
      read_random(r);
      break;
    case GRANDOM:
      read_grandom(r);
      break;
    case VERSION:
      read_version(r);
      break;
    default:
      respond(r, nil);
      break;
  }
}

void fs_destroy_file(File* f) {
  Aux* a = f->aux;
  if (a && a->data) {
    free(a->data);
    free(a);
  } else if (a) {
    free(a);
  }
}

Srv fs = {.attach = xrxs_attach, .read = xrxs_read, .write = xrxs_write};

int threadmaybackground(void) { return 1; }

void threadmain(int argc, char* argv[]) {
  char* mtpt = nil;
  char* usocket = nil;
  int i;

  /* if -h CMD is given, print the hash value of CMD */
  if (argc == 3 && scmp(argv[1], "-h")) {
    printf("%llu\n", hash(argv[2], 0));
    return;
  }

  /* if -m PATH is supplied, mount on PATH */
  /* if -s NAME is supplied, create a socket for the namespace */
  /* otherwise, just use srv() (for wrapping with socat or inetd) */

  if (argc >= 3) {
    for (i = 0; i < argc; i++) {
      if (scmp(argv[i], "-m")) {
        mtpt = argv[++i];
        printf("serving on %s", mtpt);
      } else if (scmp(argv[i], "-s")) {
        usocket = argv[++i];
        printf("serving socket namespace %s", usocket);
      }
    }
  }

  for (i = 0; i < argc; i++) {
    if (scmp(argv[i], "-d")) {
      chatty9p = 1;
    }
    if (scmp(argv[i], "-v")) {
      printf("xrxs v%s\n", version);
      threadexits(0);
    }

    if (scmp(argv[i], "-h") || scmp(argv[i], "--help")) {
      helpme(argv[0]);
    }
  }

  fs.foreground = 1;
  fs.tree = alloctree(nil, nil, DMDIR | 0777, fs_destroy_file);
  tree = fs.tree;

  closefile(createfile(tree->root, "version", nil, 0400, create_aux(VERSION)));
  closefile(
    createfile(tree->root, "ctl", nil, DMAPPEND | 0600, create_aux(CTL)));
  closefile(createfile(tree->root, "carts", nil, 0400, create_aux(CARTS)));
  closefile(createfile(tree->root, "users", nil, 0400, create_aux(USERS)));
  closefile(createfile(tree->root, "slot", nil, 0400, create_aux(SLOT)));
  closefile(createfile(tree->root, "data", nil, DMDIR | 0500, nil));
  closefile(createfile(
    walkfile(tree->root, "data"),
    "sprite",
    nil,
    0400,
    create_aux(SPRITE_DATA)));
  closefile(createfile(
    walkfile(tree->root, "data"),
    "audio",
    nil,
    0400,
    create_aux(AUDIO_DATA)));
  closefile(createfile(
    walkfile(tree->root, "data"),
    "text",
    nil,
    0400,
    create_aux(TEXT_DATA)));
  closefile(createfile(tree->root, "realms", nil, 0400, create_aux(REALMS)));
  closefile(createfile(
    tree->root,
    "universe",
    nil,
    DMAPPEND | 0600,
    create_aux(UNIVERSE)));
  closefile(
    createfile(tree->root, "scope", nil, DMAPPEND | 0600, create_aux(SCOPE)));
  closefile(createfile(tree->root, "random", nil, 0400, create_aux(RANDOM)));
  closefile(createfile(tree->root, "grandom", nil, 0400, create_aux(GRANDOM)));

  if (argc >= 3) {
    if (mtpt != nil && access(mtpt, AEXIST) < 0 && access(mtpt, AEXIST) < 0)
      sysfatal("mountpoint %s does not exist", mtpt);

    threadpostmountsrv(&fs, usocket, mtpt, MREPL | MCREATE);
    threadexits(0);
  } else {
    helpme(argv[0]);
  }
}