main.go

package main

import (
	"encoding/json"
	"errors"
	"fmt"
	"io/ioutil"
	"net/http"
	"net/http/cookiejar"
	"net/url"
	"os"
	"time"

	"github.com/aws/aws-lambda-go/lambda"
	"github.com/chuckha/renthelper/slack"
	"golang.org/x/net/publicsuffix"
)

const (
	unavailable        = "unavailable"
	slackChannelIDEnv  = "SLACK_CHANNEL_ID"
	slackOauthTokenEnv = "SLACK_OAUTH_TOKEN"
)

func main() {
	lambda.Start(handleRequest)
}

func handleRequest() (string, error) {
	SlackChannelID := os.Getenv(slackChannelIDEnv)
	SlackOauthToken := os.Getenv(slackOauthTokenEnv)

	if SlackChannelID == "" || SlackOauthToken == "" {
		return "", errors.New("must set SLACK_CHANNEL_ID and SLACK_OAUTH_TOKEN")
	}
	message, err := getMessage()
	if err != nil {
		return "", err
	}
	sc := slack.NewClient(SlackOauthToken)
	if err := sc.Post(SlackChannelID, message); err != nil {
		return "", errors.New("failed to post to slack")
	}
	return "", nil
}

func getMessage() (string, error) {
	start := time.Now().Add(2 * 24 * time.Hour).Format("2006-01-02")
	end := time.Now().Add(150 * 24 * time.Hour).Format("2006-01-02")
	fmt.Printf("Checking from %s to %s\n", start, end)
	urlFormat := "https://calendly.com/api/booking/event_types/BFEN3HYGXBSSUYOC/calendar/range?timezone=America%%2FNew_York&diagnostics=false&range_start=%s&range_end=%s&single_use_link_uuid=&embed_domain=projectcupid.cityofnewyork.us&embed_type=Inline"

	j, err := cookiejar.New(&cookiejar.Options{PublicSuffixList: publicsuffix.List})
	if err != nil {
		return "", err
	}
	client := http.Client{
		Jar: j,
	}
	u, err := url.Parse(fmt.Sprintf(urlFormat, start, end))
	if err != nil {
		return "", err
	}
	fmt.Println(u.String())
	headers := http.Header{}
	headers.Set("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8")
	headers.Set("Host", "calendly.com")
	headers.Set("User-Agent", " Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_4) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/13.1 Safari/605.1.15")
	headers.Set("Accept-Language", "en-us")
	// Don't do this or it returns brotli lol
	//	headers.Set("Accept-Encoding", "gzip, deflate, br")
	req := &http.Request{
		Method: "GET",
		URL:    u,
		Header: headers,
	}

	resp, err := client.Do(req)
	if err != nil {
		return "", err
	}
	fmt.Println(resp)
	data, err := ioutil.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}
	responseData := &response{}
	fmt.Fprintln(os.Stderr, string(data))
	if err := json.Unmarshal(data, responseData); err != nil {
		return "", err
	}
	message := ""
	for _, day := range responseData.Days {
		if day.Status != unavailable {
			message += fmt.Sprintf("*%s has availability!*\n", day.Date)
			for _, spot := range day.Spots {
				message += fmt.Sprintf("%v\n", spot)
			}
		}
	}
	if message == "" {
		return "Nothing available", nil
	}
	return message, nil
}

type response struct {
	InviteePublisherError bool
	Today                 string
	AvailabilityTimezone  string
	Days                  []struct {
		Date          string
		Status        string
		Spots         []interface{}
		InviteeEvents []interface{}
	}
}