From fd5e33af5278d1c874dc17d03a015b2e68a464fb Mon Sep 17 00:00:00 2001
From: Er2 <er2@dismail.de>
Date: Mon, 7 Mar 2022 17:53:29 +0300
Subject: [PATCH] refactoring

---
 http.lua  |  11 ++++
 main.lua  | 148 +++++++++++++++++++++++++++++++++---------------------
 readme.md |   2 +-
 tcp.lua   |  62 +++++++++++++++++++++++
 utf8.lua  |  89 ++++++++++++++++++++++++++++++++
 5 files changed, 254 insertions(+), 58 deletions(-)
 create mode 100644 http.lua
 create mode 100644 tcp.lua
 create mode 100644 utf8.lua

diff --git a/http.lua b/http.lua
new file mode 100644
index 0000000..e0f15f1
--- /dev/null
+++ b/http.lua
@@ -0,0 +1,11 @@
+
+local function _loop(b, v)
+  writeln(v, 'HTTP/1.1 200 OK', '')
+  write(v, 'Please use telnet to use this service.')
+  close(v)
+end
+
+return {
+  -- submodule
+  _loop = _loop,
+}
diff --git a/main.lua b/main.lua
index 45e7f1d..003de6c 100644
--- a/main.lua
+++ b/main.lua
@@ -1,8 +1,5 @@
-local socket = require 'socket'
-local tcp = socket.bind('*', 8080)
-tcp:settimeout(0)
 
-motd = {
+local motd = {
   '              __             ' ,
   '  ___________/__\\___________ ',
   ' /   _  _  -__ -   ___  -   \\',
@@ -21,48 +18,70 @@ motd = {
 local cls = {}
 local tmp = {}
 
-local function get(v)
-  v.buf = v.buf or ''
-  local l, err
-  while not err do
-    l, err = v.cli:receive(1)
-    if l == '\r' or l == '\n' then
-      if v.le then v.cli:send '\r\n' end
-      l, v.buf = v.buf, nil
-      break
-    elseif l == '\127'
-    then v.cli:send '\008'
-      v.buf = v.buf:sub(1, -2)
-    elseif l then
-      v.buf = v.buf.. l
-      if v.le then v.cli:send(l) end
-    end
-  end
-  return l, err
+utf8 = require '.utf8'
+
+local back = {
+  tcp = require '.tcp',
+  http = require '.http',
+--  ws = require '.ws',
+}
+
+local main = {
+  'tcp',
+--  'ws',
+}
+
+function get(v, ...)     return back[v.back].get(v, ...) end
+function close(v, ...)   return back[v.back].close(v, ...) end
+function write(v, ...)   return back[v.back].write(v, ...) end
+function writeln(v, ...) return back[v.back].writeln(v, ...) end
+
+function makev(cli, back)
+  if not cli then return end
+  return {
+    cli = cli,
+    st = 0,
+    back = back,
+  }
 end
 
-while true do
-  local cli = tcp:accept()
-  if cli then
-    cli:settimeout(0)
-    if (cli:receive() or ''):match 'GET /.* HTTP.*'
-    then cli:send('HTTP/1.1 200 OK\r\n\r\nPlease use telnet to use this service.')
-         cli:close()
-    else cli:send(table.concat(motd, '\r\n')..'\r\n')
-      table.insert(tmp, {
-        cli = cli,
-        st = 0,
-      })
+function init(v)
+  writeln(v, table.unpack(motd))
+  writeln(v, '')
+  table.insert(tmp, v)
+end
+
+function forc(fn, t, c)
+  if c == nil or c == true then
+    for k, v in pairs(cls) do
+      fn(v, k)
+      if v.closed then table.remove(cls, k) end
     end
   end
-  for k, v in pairs(tmp) do
+  if t then
+    for k, v in pairs(tmp) do
+      fn(v, k)
+      if v.closed then table.remove(tmp, k) end
+    end
+  end
+end
+
+local runs = true
+while runs do
+  for _, v in pairs(main) do
+    local p, w = back[v]._loop(v)
+    if p and back[p]
+    then back[p]._loop(v, w) end
+  end
+
+  forc(function(v, k)
     if v.reads then -- nothing
-    elseif v.st == 0 then v.cli:send('Do you need input echo? [YNQ] ')
-    elseif v.st == 1 then v.cli:send('Username: ')
-    elseif v.st == 2 then v.cli:send('Password: ')
-    elseif v.st == 3 then v.cli:send('Welcome, '.. v.user ..'!\r\n')
+    elseif v.st == 0 then write  (v, 'Do you need input echo? [YNHQ] ')
+    elseif v.st == 1 then write  (v, 'Username: ')
+    elseif v.st == 2 then write  (v, 'Password: ')
+    elseif v.st == 3 then writeln(v, 'Welcome, '.. v.user ..'!')
       for _, w in pairs(cls) do
-        w.cli:send('\r\n-- '.. v.user ..' joined --\r\n')
+        writeln(w, '', '-- '.. v.user ..' joined --')
       end
       v.st, v.reads = nil, nil
       table.remove(tmp, k)
@@ -71,30 +90,45 @@ while true do
     if v.st then v.reads = true
       local l, err = get(v)
       if err == 'timeout' then -- nothing
-      elseif err then table.remove(tmp, k)
-      elseif (l or ''):match '^%s*$' then v.reads = false
+      elseif err then close(v)
+      --elseif (l or ''):match '^%s*$' then v.reads = false
       elseif v.st == 0 then v.st, v.reads = 1, false
-        if l:match 'y'
-        then v.le = true; v.cli:send(l.. '\r\n')
-        elseif l:match 'q'
-        then v.cli:close(); table.remove(tmp, k)
+        if l:match '[Yy]'
+        then v.le = true; writeln(v, l)
+        elseif l:match '[QqEe]' then close(v)
+        elseif l:match '[Nn]' then -- nothing
+        else v.st = 0
+          writeln(v, l,
+          'Say N if you see your input twice.',
+          'Say Y if not.',
+          'Say Q to exit.')
+        end
+      elseif v.st == 1 then v.reads = false
+        if #(l:match '^%S+' or '') >= 3
+        then v.user, v.st = l:match '^%S+', 3
+        else writeln(v, 'Provide username with length >= 3 symbols')
         end
-      elseif v.st == 1 then v.st, v.user, v.reads = 3, l:match '^%S+', false
       elseif v.st == 2 then v.st, v.reads = 1, false
       end
     end
-  end
-  for k, v in pairs(cls) do
+  end, true, false)
+
+  forc(function(v, k)
     local l, err = get(v)
-    if l == '/leave' then v.cli:close(); err = 'closed'
+    if err and err ~= 'timeout'
+    then close(v) end
+    if l == '/help' then writeln(v, '-- HELP --',
+      '/leave - Close chat'
+      )
+    elseif l == '/leave' then close(v)
     end
-    if err and err ~= 'timeout' then table.remove(cls, k) end
-    for j, w in pairs(cls) do
-      if err and err ~= 'timeout'
-      then w.cli:send('\r\n-- '.. v.user ..' leaved --\r\n')
+    forc(function(w)
+      if w == v then -- ignore yourself
+      elseif v.closed
+      then writeln(w, '', '-- '.. v.user ..' leaves --')
       elseif (l or ''):match '^%s*$' then -- nothing
-      elseif k ~= j then w.cli:send('\r\n'.. v.user ..': '.. l ..'\r\n')
+      else writeln(w, '', v.user ..': '.. l)
       end
-    end
-  end
+    end)
+  end, false, true)
 end
diff --git a/readme.md b/readme.md
index b6488b3..781f3e9 100644
--- a/readme.md
+++ b/readme.md
@@ -12,7 +12,7 @@ ___|___|____/____\_____|___|___
 
      Welcome to Er2Chat!
  You need to login to continue
-Do you need input echo? [YNQ]
+Do you need input echo? [YNHQ]
 ```
 
 ---
diff --git a/tcp.lua b/tcp.lua
new file mode 100644
index 0000000..7c07c46
--- /dev/null
+++ b/tcp.lua
@@ -0,0 +1,62 @@
+local socket = require 'socket'
+local tcp = socket.bind('*', 8080)
+tcp:settimeout(0)
+
+local function get(v)
+  v.buf = v.buf or ''
+  local l, err
+  while not err do
+    l, err = v.cli:receive(1)
+    if l == '\r' or l == '\n' then
+      if v.le then writeln(v, '') end
+      local n = v.cli:receive(1)
+      if not n or n == '\n' or n == '\r'
+      then l, v.buf = v.buf, nil
+      else l = n end
+    end
+    if v.buf == nil then break
+    elseif l == '\127'
+    then write(v, '\008')
+      v.buf = utf8.sub(v.buf, 1, -2)
+    elseif l then
+      v.buf = v.buf.. l
+      if v.le then write(v, l) end
+    end
+  end
+  return l, err
+end
+
+local function write(v, ...)
+  v.cli:send(table.concat({...}, '\r\n'))
+end
+
+local function writeln(v, ...)
+  write(v, ...)
+  write(v, '\r\n')
+end
+
+local function close(v)
+  v.cli:close()
+  v.closed = true
+end
+
+local function _loop(b)
+  local v = makev(tcp:accept(), b)
+  if v then
+    v.cli:settimeout(0)
+    local l = v.cli:receive()
+    if (l or ''):match 'GET /.* HTTP.*' then
+      return 'http', v
+    else init(v)
+    end
+  end
+end
+
+return {
+  get = get,
+  write = write,
+  writeln = writeln,
+  close = close,
+  _loop = _loop,
+  tcp = tcp,
+}
diff --git a/utf8.lua b/utf8.lua
new file mode 100644
index 0000000..e730f22
--- /dev/null
+++ b/utf8.lua
@@ -0,0 +1,89 @@
+-- Unicode library
+
+local pattern = '[%z\1-\127\194-\244][\128-\191]*'
+
+-- helper function
+local function posrelat(pos, len)
+  if pos < 0 then
+    pos = len + pos + 1
+  end
+  return pos
+end
+
+local utf8 = {}
+
+-- THE MEAT
+
+function utf8.map(s, f, no_subs)
+  local i = 0
+
+  if no_subs then
+    for b, e in s:gmatch('()' .. pattern .. '()') do
+      i = i + 1
+      local c = e - b
+      f(i, c, b)
+    end
+  else
+    for b, c in s:gmatch('()(' .. pattern .. ')') do
+      i = i + 1
+      f(i, c, b)
+    end
+  end
+end
+
+-- THE REST
+
+function utf8.chars(s, no_subs)
+  return coroutine.wrap(function()
+    return utf8.map(s, coroutine.yield, no_subs)
+  end)
+end
+
+function utf8.len(s)
+  return select(2, s:gsub('[^\128-\193]', ''))
+end
+
+function utf8.replace(s, map)
+  return s:gsub(pattern, map)
+end
+
+function utf8.reverse(s)
+  s = s:gsub(pattern, function(c)
+    return #c > 1 and c:reverse()
+  end)
+  return s:reverse()
+end
+
+function utf8.strip(s)
+  return s:gsub(pattern, function(c)
+    return #c > 1 and ''
+  end)
+end
+
+function utf8.sub(s, i, j)
+  local l = utf8.len(s)
+
+  i = posrelat(i, l)
+  j = j and posrelat(j, l) or l
+
+  if i < 1 then i = 1 end
+  if j > l then j = l end
+  if i > j then return '' end
+
+  local diff = j - i
+  local iter = utf8.chars(s, true)
+
+  for _ = 1, i - 1 do iter() end
+  local c, b = select(2, iter())
+
+  if diff == 0
+  then return s:sub(b, b + c - 1) end
+
+  i = b
+  for _ = 1, diff - 1 do iter() end
+  local c, b = select(2, iter())
+
+  return s:sub(i, b + c - 1)
+end
+
+return utf8