package main

import (
	"encoding/json"
	"errors"
	"fmt"
	"net/http"
	"net/url"
)

const BaseURL = "https://www.google.com/complete/search?output=search&client=chrome&hl=zh-CN&q=" 
func main() {
	query := "apples and oranges"

	suggestions, err := Get(query)

	if err != nil {
		panic(err)
	}

	for _, suggestion := range suggestions {
		fmt.Println(suggestion)
	}
}

// Suggestions is a slice of strings that is returned by Suggest
type Suggestions = []string

// Get queries google's unofficial suggestion API for Suggestions.
func Get(str string) (Suggestions, error) {
	query := url.QueryEscape(str)

	resp, err := http.Get(BaseURL + query)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	raw := []json.RawMessage{}

	err = json.NewDecoder(resp.Body).Decode(&raw)
	if err != nil {
		return nil, err
	}

	if len(raw) < 2 {
		return nil, errors.New("no suggestion data found")
	}

	sgs := Suggestions{}

	err = json.Unmarshal(raw[1], &sgs)
	if err != nil {
		return nil, err
	}

	return sgs, nil
}

client := &http.Client{}
req, err := http.NewRequest("GET", BaseURL+query, nil)
if err != nil {
	return nil, err
}
req.Header.Set("User-Agent", "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.54 Safari/537.36")
resp, err := client.Do(req)