From fee1bd351e5f427850fd2f238559b60863ecfaa1 Mon Sep 17 00:00:00 2001
From: hkc <hatkidchan@gmail.com>
Date: Tue, 9 Jan 2024 20:08:49 +0300
Subject: [PATCH] It doesn't really like symlinks

---
 augment/wsvpn.lua | 155 +++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 154 insertions(+), 1 deletion(-)
 mode change 120000 => 100644 augment/wsvpn.lua

diff --git a/augment/wsvpn.lua b/augment/wsvpn.lua
deleted file mode 120000
index 60c2a7f..0000000
--- a/augment/wsvpn.lua
+++ /dev/null
@@ -1 +0,0 @@
-../wsvpn.lua
\ No newline at end of file
diff --git a/augment/wsvpn.lua b/augment/wsvpn.lua
new file mode 100644
index 0000000..edab371
--- /dev/null
+++ b/augment/wsvpn.lua
@@ -0,0 +1,154 @@
+local expect = require("cc.expect")
+
+local WSModem = {
+  open = function(self, channel)
+    expect.expect(1, channel, "number")
+    expect.range(channel, 0, 65535)
+    self._request(0x4f, {
+        bit.band(0xFF, bit.brshift(channel, 8)),
+        bit.band(0xFF, channel)
+      })
+  end,
+  isOpen = function(self, channel)
+    expect.expect(1, channel, "number")
+    expect.range(channel, 0, 65535)
+    return self._request(0x6f, {
+        bit.band(0xFF, bit.brshift(channel, 8)),
+        bit.band(0xFF, channel)
+      })[1] ~= 0
+  end,
+  close = function(self, channel)
+    expect.expect(1, channel, "number")
+    expect.range(channel, 0, 65535)
+    self._request(0x63, {
+        bit.band(0xFF, bit.brshift(channel, 8)),
+        bit.band(0xFF, channel)
+      })
+  end,
+  closeAll = function(self)
+    self._request(0x43)
+  end,
+  transmit = function(self, channel, replyChannel, data)
+    expect.expect(1, channel, "number")
+    expect.expect(2, replyChannel, "number")
+    expect.expect(3, data, "nil", "string", "number", "table")
+    expect.range(channel, 0, 65535)
+    expect.range(replyChannel, 0, 65535)
+
+    local serialized = textutils.serializeJSON(data)
+    expect.range(#serialized, 0, 65535)
+    serialized = { serialized:byte(1, 65536) }
+    self._request(0x54, {
+        bit.band(0xFF, bit.brshift(channel, 8)),
+        bit.band(0xFF, channel),
+        bit.band(0xFF, bit.brshift(replyChannel, 8)),
+        bit.band(0xFF, replyChannel),
+        bit.band(0xFF, bit.brshift(#serialized, 8)),
+        bit.band(0xFF, #serialized),
+        table.unpack(serialized, 1, #serialized)
+      })
+  end,
+  isWireless = function(self) return true end,
+  run = function(self)
+    while true do
+      local data, binary = self._socket.receive()
+      if not data then return true end
+      if binary == false then return false, "Not a binary message" end
+      data = { string.byte(data, 1, #data) }
+      local opcode = table.remove(data, 1)
+      if opcode == 0x49 then -- info
+        local len, msg = self._read_u16ne(data)
+        msg = string.char(table.unpack(msg))
+        os.queueEvent("wsvpn:info", msg)
+      elseif opcode == 0x41 then -- Set address/side
+        local len = table.remove(data, 1)
+        self.side = string.char(table.unpack(data, 1, len))
+      elseif opcode == 0x45 then -- Error
+        local request_id, error_length
+        request_id, data = self._read_u16ne(data)
+        error_length, data = self._read_u16ne(data)
+        local message = string.char(table.unpack(data, 1, error_length))
+        os.queueEvent("wsvpn:response", false, request_id, message)
+      elseif opcode == 0x52 then -- Response
+        local request_id, response = self._read_u16ne(data)
+        os.queueEvent("wsvpn:response", true, request_id, response)
+      elseif opcode == 0x54 then -- Transmission
+        local channel, replyChannel, dataSize, packet
+        channel, data = self._read_u16ne(data)
+        replyChannel, data = self._read_u16ne(data)
+        dataSize, packet = self._read_u16ne(data)
+        os.queueEvent("modem_message", self.side or "wsmodem_0", channel, replyChannel, textutils.unserializeJSON(string.char(table.unpack(data, 1, dataSize))), nil)
+      else
+        return false, string.format("Invalid opcode 0x%02x", opcode)
+      end
+      os.sleep(0)
+    end
+  end,
+
+  -- low-level part
+
+  _read_u16ne = function(self, data)
+    local v = bit.blshift(table.remove(data, 1), 8)
+    v = bit.bor(v, table.remove(data, 1))
+    return v, data
+  end,
+
+  _wait_response = function(self, request_id)
+    while true do
+      local ev, status, id, data = os.pullEvent("wsvpn:response")
+      if ev == "wsvpn:response" and id == request_id then
+        return status, data
+      end
+    end
+  end,
+
+  _request = function(self, opcode, data)
+    local request_id = self._get_id()
+    self._socket.send(
+      string.char(
+        opcode,
+        bit.band(0xFF, bit.brshift(request_id, 8)),
+        bit.band(0xFF, request_id),
+        table.unpack(data or {})
+        ),
+      true
+      )
+    local status, response = self._wait_response(request_id)
+    if not status then
+      error(response)
+    end
+    return response
+  end,
+
+  _get_id = function(self)
+    self._req_id = bit.band(0xFFFF, self._req_id + 1)
+    return self._req_id
+  end,
+
+  _send_text = function(self, code, fmt, ...)
+    local msg = { fmt:format(...):byte(1, 1020) }
+    self._socket.send(
+      string.char(
+        code,
+        bit.band(0xFF, bit.brshift(#msg, 8)),
+        bit.band(0xFF, #msg),
+        table.unpack(msg, 1, #msg)
+      ),
+      true
+    )
+  end,
+
+  _init = function(self)
+    self._send_text(0x49, "Hello! I'm computer %d", os.getComputerID())
+  end,
+}
+
+return function(addr)
+  local ws = assert(http.websocket(addr))
+  local sock = setmetatable({ _socket = ws, _req_id = 0, side = "wsmodem_unknown" }, { __index = WSModem })
+  for name, method in pairs(WSModem) do
+    sock[name] = function(...) return method(sock, ...) end
+  end
+  sock._init()
+  return sock
+end