package pixiv

import (
	"fmt"
	"log"
	"net/http"
	"os"
	"regexp"

	"h12.io/socks"
)

//Pixiv is API
type Pixiv struct {
	phpsessid       http.Cookie
	Ua              string
	client          *http.Client
	RetryCount      int
	ItemsPerRequest int
	WorkDirectory   string
	logChannel      chan string
	DownloadChannel chan Illust
	setxattr        bool
	nameMatcher     *regexp.Regexp
	idSubexpNumbers []int
}

//New returns object with methods to access API functions
func New(cookies string, logFilePath string, threads int, xattrs bool) (p Pixiv) {
	p.phpsessid = http.Cookie{Name: "PHPSESSID", Value: cookies}
	p.Ua = "Mozilla/5.0 (Windows NT 10.0; rv:78.0) Gecko/20100101 Firefox/78.0"
	p.client = &http.Client{}
	p.RetryCount = 5
	p.ItemsPerRequest = 100
	p.WorkDirectory = fmt.Sprintf("%s/Pictures/pixiv", os.Getenv("HOME"))
	p.setxattr = xattrs
	p.nameMatcher = regexp.MustCompile(typicalFilenamesRegex)
	if len(logFilePath) > 0 {
		logfile, err := os.OpenFile(logFilePath, os.O_APPEND, 664)
		if err != nil {
			log.Fatal(err.Error())
		}
		p.logChannel = make(chan string)
		go p.logger(logfile)
	} else {
		p.logChannel = make(chan string)
		go p.logger(os.Stdout)
	}
	p.DownloadChannel = make(chan Illust)
	for i := 0; i < threads; i++ {
		go p.downloadWorker()
	}

	return
}

//Close .
func (p *Pixiv) Close() {
	close(p.logChannel)
	close(p.DownloadChannel)
}

func (p *Pixiv) logger(logfile *os.File) {
	for entry := range p.logChannel {
		logfile.WriteString(entry)
	}
	log.Println("Closing log file")
	logfile.Close()
}

//SetProxy sets SOCKS proxy for all requests
func (p *Pixiv) SetProxy(proxy string) (err error) {
	dialSocksProxy := socks.Dial(proxy)
	tr := &http.Transport{Dial: dialSocksProxy}
	p.client.Transport = tr
	return
}

// TypicalFilenamesMatcher matches typical pixiv's filenames. Returns ok if strings match and id extracted from string.
func (p *Pixiv) TypicalFilenamesMatcher(name string) (ok bool, id string) {
	ok = p.nameMatcher.MatchString(name)
	if ok {
		for subexpIndex, subexpName := range p.nameMatcher.SubexpNames() {
			if subexpIndex == 0 {
				// we don't need main expression here
				continue
			}
			// try to read ID with each subexp and return on first match
			id = p.nameMatcher.ReplaceAllString(name, fmt.Sprintf("${%s}", subexpName))
			if len(id) > 0 {
				break
			}
		}
	}
	return
}