1 files changed, 155 insertions, 0 deletions
diff --git a/server/src/lsp.lua b/server/src/lsp.lua
new file mode 100644
index 00000000..4a88aba6
--- /dev/null
+++ b/server/src/lsp.lua
@@ -0,0 +1,155 @@
+local json   = require 'json'
+local parser = require 'parser'
+
+local ErrorCodes = {
+	-- Defined by JSON RPC
+	ParseError           = -32700,
+	InvalidRequest       = -32600,
+	MethodNotFound       = -32601,
+	InvalidParams        = -32602,
+	InternalError        = -32603,
+	serverErrorStart     = -32099,
+	serverErrorEnd       = -32000,
+	ServerNotInitialized = -32002,
+	UnknownErrorCode     = -32001,
+
+	-- Defined by the protocol.
+	RequestCancelled     = -32800,
+}
+
+local mt = {}
+mt.__index = mt
+
+mt._input = nil
+mt._output = nil
+mt._method = nil
+mt._file = nil
+
+function mt:_callback(method, params)
+    local f = self._method
+    if f then
+        return f(method, params)
+    end
+    return nil, '没有注册method'
+end
+
+function mt:_send(data)
+    local f = self._output
+    if not f then
+        return
+    end
+    data.jsonrpc = '2.0'
+    local content = json.encode(data)
+    local buf = ('Content-Length: %d\r\n\r\n%s'):format(#content, content)
+    f(buf)
+end
+
+function mt:_readAsContent(header)
+    local len = tonumber(header:match('%d+'))
+    if not len then
+        log.error('错误的协议头：', header)
+        return
+    end
+    local buf = self:read(len+2)
+    local suc, res = pcall(json.decode, buf)
+    if not suc then
+        log.error('错误的协议：', buf)
+        return
+    end
+    local id     = res.id
+    local method = res.method
+    local params = res.params
+    local response, err = self:_callback(method, params)
+    if id then
+        if response then
+            self:_send {
+                id = id,
+                result = response,
+            }
+        else
+            self:_send {
+                id = id,
+                error = {
+                    code = ErrorCodes.UnknownErrorCode,
+                    message = err or ('没有回应：' .. method),
+                },
+            }
+        end
+    end
+    if not response then
+        log.error(err or ('没有回应：' .. method))
+    end
+    -- 运行时不清理垃圾，在回复前端之后清理垃圾
+    collectgarbage()
+end
+
+function mt:setInput(input)
+    self._input = input
+end
+
+function mt:setOutput(output)
+    self._output = output
+end
+
+function mt:read(mode)
+    if not self._input then
+        return nil
+    end
+    return self._input(mode)
+end
+
+function mt:saveText(uri, version, text)
+    local obj = self._file[uri]
+    if obj then
+        if obj.version >= version then
+            return
+        end
+        obj.version = version
+        obj.text = text
+    else
+        self._file[uri] = {
+            version = version,
+            text = text,
+        }
+    end
+end
+
+function mt:loadText(uri)
+    local obj = self._file[uri]
+    if not obj then
+        return nil
+    end
+    return obj.text
+end
+
+function mt:removeText(uri)
+    self._file[uri] = nil
+end
+
+function mt:start(method)
+    self._method = method
+    while true do
+        local header = self:read 'l'
+        if not header then
+            return
+        end
+        if header:sub(1, #'Content-Length') == 'Content-Length' then
+            self:_readAsContent(header)
+        elseif header:sub(1, #'Content-Type') == 'Content-Type' then
+        else
+            log.error('错误的协议头：', header)
+        end
+    end
+    return true
+end
+
+function mt:stop()
+    self._input = nil
+    self._output = nil
+end
+
+return function ()
+    return setmetatable({
+        _file = {},
+    }, mt)
+end