package crawler

import (
	"encoding/json"
	"errors"
	"io/ioutil"
	"log"
	"loafle.com/overflow/crawler_go/config"
)

type Internal interface {
	Internal(params config.Config) ([]byte, error)
}

type Crawler interface {
	Init(path string) ([]byte, error)
	Add(id string) ([]byte, error)
	Remove(id string) ([]byte, error)
	Get(id string) ([]byte, error)
}

type CrawlerImpl struct {
	Crawler
	configs    map[string] config.Config
	internal   Internal
	configPath string
}

func (c *CrawlerImpl) Init(path string) ([]byte, error) {
	if c.configs == nil {
		c.configs = make(map[string]config.Config, 0)
	}

	c.configPath = path
	files, err := ioutil.ReadDir(c.configPath)
	if err != nil {
		log.Panic(err)
	}

	for _, file := range files {
		if file.IsDir() == true {
			continue
		}
		_,err := c.Add(file.Name())
		if err != nil {
			log.Panic(err)
		}
	}

	// load all file in path
	return json.Marshal(true)
}
func (c *CrawlerImpl) Add(id string) ([]byte, error) {
	
	b, err := ioutil.ReadFile(c.configPath + id)
	if err != nil {
		log.Panic(err)
	}
	
	var m = config.Config{}
	json.Unmarshal(b, &m)
	c.configs[id] = m
	
	return json.Marshal(true)
}
func (c *CrawlerImpl) Remove(id string) ([]byte, error) {
	//remove in config
	delete(c.configs,id)
	return json.Marshal(true)
}
func (c *CrawlerImpl) Get(id string) ([]byte, error) {

	if c.internal != nil {
		out, err := c.internal.Internal(c.GetConfig(id))
		if err != nil {
			//set error fail, message
			return nil, err
		}
		return out, nil
	}
	return nil, errors.New("Not Assign")
}

// internal methods
func (c *CrawlerImpl) GetConfig(id string) config.Config {
	return c.configs[id]
}
func (c *CrawlerImpl) SetInternal(i Internal) {
	c.internal = i
}
func (c *CrawlerImpl) PutConfig(name string, m config.Config) {
	if c.configs == nil {
		c.configs = make(map[string]config.Config, 0)
	}
	c.configs[name] = m
}