wide/playground/autocomplete.go

112 lines
2.8 KiB
Go

// Copyright (c) 2014-present, b3log.org
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package playground
import (
"bytes"
"encoding/json"
"net/http"
"os"
"os/exec"
"strconv"
"strings"
"github.com/88250/gulu"
"github.com/88250/wide/conf"
"github.com/88250/wide/session"
)
// AutocompleteHandler handles request of code autocompletion.
func AutocompleteHandler(w http.ResponseWriter, r *http.Request) {
if conf.Wide.ReadOnly {
http.Error(w, "Forbidden", http.StatusForbidden)
return
}
var args map[string]interface{}
if err := json.NewDecoder(r.Body).Decode(&args); err != nil {
logger.Error(err)
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
session, _ := session.HTTPSession.Get(r, session.CookieName)
if session.IsNew {
http.Error(w, "Forbidden", http.StatusForbidden)
return
}
code := args["code"].(string)
line := int(args["cursorLine"].(float64))
ch := int(args["cursorCh"].(float64))
file, err := os.Create("wide_autocomplete_" + gulu.Rand.String(16) + ".go")
if nil != err {
logger.Error(err)
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
file.WriteString(code)
file.Close()
path := file.Name()
defer os.Remove(path)
offset := getCursorOffset(code, line, ch)
argv := []string{"-f=json", "--in=" + path, "autocomplete", strconv.Itoa(offset)}
gocode := gulu.Go.GetExecutableInGOBIN("gocode")
cmd := exec.Command(gocode, argv...)
output, err := cmd.CombinedOutput()
if nil != err {
logger.Error(err)
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
w.Header().Set("Content-Type", "application/json")
w.Write(output)
}
// getCursorOffset calculates the cursor offset.
//
// line is the line number, starts with 0 that means the first line
// ch is the column number, starts with 0 that means the first column
func getCursorOffset(code string, line, ch int) (offset int) {
lines := strings.Split(code, "\n")
// calculate sum length of lines before
for i := 0; i < line; i++ {
offset += len(lines[i])
}
// calculate length of the current line and column
curLine := lines[line]
var buffer bytes.Buffer
r := []rune(curLine)
for i := 0; i < ch; i++ {
buffer.WriteString(string(r[i]))
}
offset += len(buffer.String()) // append length of current line
offset += line // append number of '\n'
return offset
}