package realdebrid

import (
	"fmt"
	"io"
	"net/http"
	"net/url"
	"strings"

	"github.com/debridmediamanager/zurg/internal/config"
	zurghttp "github.com/debridmediamanager/zurg/pkg/http"
	"github.com/debridmediamanager/zurg/pkg/logutil"
	"github.com/panjf2000/ants/v2"
)

type RealDebrid struct {
	torrentsCache    []Torrent
	apiClient        *zurghttp.HTTPClient
	unrestrictClient *zurghttp.HTTPClient
	downloadClient   *zurghttp.HTTPClient
	workerPool       *ants.Pool
	cfg              config.ConfigInterface
	log              *logutil.Logger
}

func NewRealDebrid(apiClient, unrestrictClient, downloadClient *zurghttp.HTTPClient, workerPool *ants.Pool, cfg config.ConfigInterface, log *logutil.Logger) *RealDebrid {
	rd := &RealDebrid{
		torrentsCache:    []Torrent{},
		apiClient:        apiClient,
		unrestrictClient: unrestrictClient,
		downloadClient:   downloadClient,
		workerPool:       workerPool,
		cfg:              cfg,
		log:              log,
	}
	rd.readCachedTorrents()
	return rd
}

// currently unused
func (rd *RealDebrid) UnrestrictCheck(link string) (*Download, error) {
	data := url.Values{}
	data.Set("link", link)
	requestBody := strings.NewReader(data.Encode())

	req, err := http.NewRequest(http.MethodPost, "https://api.real-debrid.com/rest/1.0/unrestrict/check", requestBody)
	if err != nil {
		rd.log.Errorf("Error when creating a unrestrict check request: %v", err)
		return nil, err
	}
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")

	resp, err := rd.unrestrictClient.Do(req)
	if err != nil {
		rd.log.Errorf("Error when executing the unrestrict check request: %v", err)
		return nil, err
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		rd.log.Errorf("Error when reading the body of unrestrict check response: %v", err)
		return nil, err
	}

	var response Download
	err = json.Unmarshal(body, &response)
	if err != nil {
		rd.log.Errorf("Error when decoding unrestrict check JSON: %v", err)
		return nil, err
	}

	rd.log.Debugf("Link %s is streamable? %v", response.Streamable)
	return &response, nil
}

func (rd *RealDebrid) UnrestrictLink(link string, verifyDownloadURL bool) (*Download, error) {
	data := url.Values{}
	if strings.HasPrefix(link, "https://real-debrid.com/d/") {
		// set link to max 39 chars
		link = link[0:39]
	}
	data.Set("link", link)
	requestBody := strings.NewReader(data.Encode())

	req, err := http.NewRequest(http.MethodPost, "https://api.real-debrid.com/rest/1.0/unrestrict/link", requestBody)
	if err != nil {
		rd.log.Errorf("Error when creating a unrestrict link request: %v", err)
		return nil, err
	}

	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")

	// at this point, any errors mean that the link has expired and we need to repair it
	resp, err := rd.unrestrictClient.Do(req)
	if err != nil {
		// rd.log.Errorf("Error when executing the unrestrict link request: %v", err)
		return nil, fmt.Errorf("unrestrict link request failed: %v", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		// rd.log.Errorf("Error when reading the body of unrestrict link response: %v", err)
		return nil, fmt.Errorf("unreadable body: %v", err)
	}

	var response Download
	err = json.Unmarshal(body, &response)
	if err != nil {
		// rd.log.Errorf("Error when decoding unrestrict link JSON: %v", err)
		return nil, fmt.Errorf("undecodable response: %v", err)
	}

	// will only check for first byte if serving from rclone
	if verifyDownloadURL {
		err := rd.downloadClient.VerifyURL(response.Download)
		if err != nil {
			return nil, err
		}
	}

	// rd.log.Debugf("Unrestricted link %s into %s", link, response.Download)
	return &response, nil
}

func (rd *RealDebrid) GetTorrentInfo(id string) (*TorrentInfo, error) {
	url := "https://api.real-debrid.com/rest/1.0/torrents/info/" + id

	req, err := http.NewRequest(http.MethodGet, url, nil)
	if err != nil {
		rd.log.Errorf("Error when creating a get info request: %v", err)
		return nil, err
	}

	resp, err := rd.apiClient.Do(req)
	if err != nil {
		rd.log.Errorf("Error when executing the get info request: %v", err)
		return nil, err
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		rd.log.Errorf("Error when reading the body of get info response: %v", err)
		return nil, err
	}

	var response TorrentInfo
	err = json.Unmarshal(body, &response)
	if err != nil {
		rd.log.Errorf("Error when : %v", err)
		return nil, err
	}

	// rd.log.Debugf("Got info for torrent %s (progress=%d%%)", id, response.Progress)
	return &response, nil
}

// SelectTorrentFiles selects files of a torrent to start it.
func (rd *RealDebrid) SelectTorrentFiles(id string, files string) error {
	data := url.Values{}
	data.Set("files", files)
	requestBody := strings.NewReader(data.Encode())

	reqURL := fmt.Sprintf("https://api.real-debrid.com/rest/1.0/torrents/selectFiles/%s", id)
	req, err := http.NewRequest(http.MethodPost, reqURL, requestBody)
	if err != nil {
		rd.log.Errorf("Error when creating a select files request: %v", err)
		return err
	}

	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")

	resp, err := rd.apiClient.Do(req)
	if err != nil {
		rd.log.Errorf("Error when executing the select files request: %v", err)
		return err
	}
	defer resp.Body.Close()

	rd.log.Debugf("Selected %d files and started the download for torrent id=%s (status code: %d)", len(strings.Split(files, ",")), id, resp.StatusCode)
	return nil
}

// DeleteTorrent deletes a torrent from the torrents list.
func (rd *RealDebrid) DeleteTorrent(id string) error {
	// Construct request URL
	reqURL := fmt.Sprintf("https://api.real-debrid.com/rest/1.0/torrents/delete/%s", id)
	req, err := http.NewRequest(http.MethodDelete, reqURL, nil)
	if err != nil {
		rd.log.Errorf("Error when creating a delete torrent request: %v", err)
		return err
	}

	// Send the request
	resp, err := rd.apiClient.Do(req)
	if err != nil {
		rd.log.Errorf("Error when executing the delete torrent request: %v", err)
		return err
	}
	defer resp.Body.Close()

	rd.log.Debugf("Deleted torrent with id=%s", id)
	return nil
}

// AddMagnetHash adds a magnet link to download.
func (rd *RealDebrid) AddMagnetHash(magnet string) (*MagnetResponse, error) {
	// Prepare request data
	data := url.Values{}
	data.Set("magnet", fmt.Sprintf("magnet:?xt=urn:btih:%s", magnet))
	requestBody := strings.NewReader(data.Encode())

	// Construct request URL
	reqURL := "https://api.real-debrid.com/rest/1.0/torrents/addMagnet"
	req, err := http.NewRequest(http.MethodPost, reqURL, requestBody)
	if err != nil {
		rd.log.Errorf("Error when creating an add magnet request: %v", err)
		return nil, err
	}

	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")

	// Send the request
	resp, err := rd.apiClient.Do(req)
	if err != nil {
		rd.log.Errorf("Error when executing the add magnet request: %v", err)
		return nil, err
	}
	defer resp.Body.Close()

	var response MagnetResponse
	err = json.NewDecoder(resp.Body).Decode(&response)
	if err != nil {
		rd.log.Errorf("Error when decoding add magnet JSON: %v", err)
		return nil, err
	}

	rd.log.Debugf("Added magnet %s with id=%s", magnet, response.ID)
	return &response, nil
}

// GetActiveTorrentCount gets the number of currently active torrents and the current maximum limit.
func (rd *RealDebrid) GetActiveTorrentCount() (*ActiveTorrentCountResponse, error) {
	// Construct request URL
	reqURL := "https://api.real-debrid.com/rest/1.0/torrents/activeCount"
	req, err := http.NewRequest(http.MethodGet, reqURL, nil)
	if err != nil {
		rd.log.Errorf("Error when creating a active torrents request: %v", err)
		return nil, err
	}

	// Send the request
	resp, err := rd.apiClient.Do(req)
	if err != nil {
		rd.log.Errorf("Error when executing the active torrents request: %v", err)
		return nil, err
	}
	defer resp.Body.Close()

	var response ActiveTorrentCountResponse
	err = json.NewDecoder(resp.Body).Decode(&response)
	if err != nil {
		rd.log.Errorf("Error when decoding active torrents JSON: %v", err)
		return nil, err
	}
	return &response, nil
}

// GetUserInformation gets the current user information.
func (rd *RealDebrid) GetUserInformation() (*User, error) {
	// Construct request URL
	reqURL := "https://api.real-debrid.com/rest/1.0/user"
	req, err := http.NewRequest(http.MethodGet, reqURL, nil)
	if err != nil {
		rd.log.Errorf("Error when creating a user information request: %v", err)
		return nil, err
	}

	// Send the request
	resp, err := rd.apiClient.Do(req)
	if err != nil {
		rd.log.Errorf("Error when executing the user information request: %v", err)
		return nil, err
	}
	defer resp.Body.Close()

	// Decode the JSON response into the User struct
	var user User
	err = json.NewDecoder(resp.Body).Decode(&user)
	if err != nil {
		rd.log.Errorf("Error when decoding user information JSON: %v", err)
		return nil, err
	}

	return &user, nil
}

// AvailabilityCheck checks the instant availability of torrents
func (rd *RealDebrid) AvailabilityCheck(hashes []string) (AvailabilityResponse, error) {
	if len(hashes) == 0 {
		return nil, fmt.Errorf("no hashes provided")
	}

	baseURL := "https://api.real-debrid.com/rest/1.0"
	url := fmt.Sprintf("%s/torrents/instantAvailability/%s", baseURL, strings.Join(hashes, "/"))
	req, err := http.NewRequest(http.MethodGet, url, nil)
	if err != nil {
		return nil, err
	}

	resp, err := rd.apiClient.Do(req)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()

	var response AvailabilityResponse
	err = json.NewDecoder(resp.Body).Decode(&response)
	if err != nil {
		return nil, err
	}

	return response, nil
}