package proxy

import (
	"context"
	"fmt"
	"log/slog"
	"math/rand"
	"os"
	"sync"
	"time"

	"github.com/golang/glog"
	"github.com/timerzz/proxypool/pkg/getter"
	"github.com/timerzz/proxypool/pkg/proxy"
	"github.com/timerzz/proxypool/pkg/tool"
)

type ProxyPool struct {
	m       sync.Mutex
	proxies proxy.ProxyList
	cfg     *Option
	updated time.Time
}

func InitDefaultProxyPool() (*ProxyPool, error) {
	path := os.Getenv(ProxyConfigEnv)
	if path == "" {
		path = DefaultProxyConfigPath
	}
	cfg, err := LoadProxyConfig(path)
	if err != nil {
		return nil, fmt.Errorf("获取代理池配置失败：%v", err)
	}
	return NewProxyPool(cfg), nil
}
func NewProxyPool(cfg *Option) *ProxyPool {
	var p = &ProxyPool{}
	p.cfg = cfg
	p.Update()
	return p
}

func (p *ProxyPool) Status() (proxy.ProxyList, time.Time) {
	return p.proxies, p.updated
}

// Update 更新代理池
func (p *ProxyPool) Update() {
	var list = make(proxy.ProxyList, 0, len(p.proxies))
	var getters = make([]getter.Getter, 0, len(p.cfg.Clash)+len(p.cfg.Subscribes))
	for _, url := range p.cfg.Subscribes {
		gtr, err := getter.NewSubscribe(tool.Options{"url": url})
		if err != nil {
			slog.Warn(fmt.Sprintf("创建Subscribe Getter失败：%v", err))
			continue
		}
		getters = append(getters, gtr)
	}
	for _, url := range p.cfg.Clash {
		gtr, err := getter.NewClashGetter(tool.Options{"url": url})
		if err != nil {
			slog.Warn(fmt.Sprintf("创建Clash Getter失败：%v", err))
			continue
		}
		getters = append(getters, gtr)
	}

	for _, gtr := range getters {
		list = list.UniqAppendProxyList(gtr.Get())
	}

	glog.Infof("代理源共 %d 个: %v", len(p.cfg.Subscribes), p.cfg.Subscribes)
	glog.Infof("获取代理共 %d 个", len(list))
	p.m.Lock()
	p.proxies = list
	p.m.Unlock()
	p.updated = time.Now()
}

// CronUpdate 定时更新
func (p *ProxyPool) CronUpdate(ctx context.Context) {
	if p.cfg.Interval == 0 {
		p.cfg.Interval = time.Minute * 30
	}
	ticker := time.NewTicker(p.cfg.Interval)
	defer ticker.Stop()
	for {
		select {
		case <-ctx.Done():
			return
		case <-ticker.C:
			p.Update()
		}
	}
}

// RandomIterator 获取随机代理的迭代器
func (p *ProxyPool) RandomIterator() func() proxy.Proxy {
	return func() (proxy proxy.Proxy) {
		if len(p.proxies) == 0 {
			return nil
		}
		p.m.Lock()
		defer p.m.Unlock()
		curIndex := rand.Intn(len(p.proxies))
		return p.proxies[curIndex]
	}
}