canopeas/falseknees/falseknees.go

131 lines
2.6 KiB
Go

package falseknees
import (
"context"
"errors"
"fmt"
"io/ioutil"
"math/rand"
"net/http"
"regexp"
"strconv"
"time"
)
var (
updateInterval = time.Minute * 30
baseURL = "https://www.falseknees.com/"
currentRe = regexp.MustCompile(`window\.location\.href.+"(.+)\.html"`)
imageRe = regexp.MustCompile(`src="(imgs.+\.png)".+title="(.+)"`)
current int
lastUpdate time.Time
)
// Comic is a FalseKnees comic
type Comic struct {
Num int
Title string
Img string
}
// Comic returns a specific Comic
func (c *Client) Comic(ctx context.Context, num int) (*Comic, error) {
return c.comic(ctx, num)
}
// Current returns the current Comic
func (c *Client) Current(ctx context.Context) (*Comic, error) {
if err := c.updateCurrent(ctx); err != nil {
return nil, err
}
return c.Comic(ctx, current)
}
// Random returns a random Comic
func (c *Client) Random(ctx context.Context) (*Comic, error) {
if err := c.updateCurrent(ctx); err != nil {
return nil, err
}
rand.Seed(time.Now().UnixNano())
return c.Comic(ctx, rand.Intn(current)+1)
}
func (c *Client) updateCurrent(ctx context.Context) error {
now := time.Now()
if !lastUpdate.IsZero() && lastUpdate.After(now.Add(-updateInterval)) {
return nil
}
lastUpdate = now
u := fmt.Sprintf("%sindex.html", baseURL)
req, err := http.NewRequestWithContext(ctx, http.MethodGet, u, nil)
if err != nil {
return err
}
resp, err := c.http.Do(req)
if err != nil {
return err
}
if resp.StatusCode != http.StatusOK {
return fmt.Errorf("could not get page for index: %s", resp.Status)
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return err
}
defer resp.Body.Close()
match := currentRe.FindStringSubmatch(string(body))
if len(match) == 0 {
return errors.New("could not find current comic")
}
curr, err := strconv.Atoi(match[1])
if err != nil {
return err
}
current = curr
return nil
}
func (c *Client) comic(ctx context.Context, num int) (*Comic, error) {
u := fmt.Sprintf("%s%d.html", baseURL, num)
req, err := http.NewRequestWithContext(ctx, http.MethodGet, u, nil)
if err != nil {
return nil, err
}
resp, err := c.http.Do(req)
if err != nil {
return nil, err
}
if resp.StatusCode != http.StatusOK {
return nil, fmt.Errorf("could not get page for comic %d: %s", num, resp.Status)
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
return nil, err
}
defer resp.Body.Close()
match := imageRe.FindStringSubmatch(string(body))
if len(match) == 0 {
return nil, fmt.Errorf("could not find comic #%d", num)
}
return &Comic{
Num: num,
Title: match[2],
Img: fmt.Sprintf("%s%s", baseURL, match[1]),
}, nil
}