package main

import (
	"database/sql/driver"
	"encoding/json"
	"encoding/xml"
	"fmt"
	"net/http"
	"strings"
)

type Api interface {
	AuthGetToken(*http.Request) ApiResponse
	AuthGetSession(*http.Request) ApiResponse
	AuthGetMobileSession(*http.Request) ApiResponse
	TrackScrobble(*http.Request) (ApiResponse, error)
}

type ApiResponse interface {
}

type SuspendScrobbles Scrobbles

func (s Scrobbles) MarshalJSON() ([]byte, error) {
	return json.Marshal(&struct {
		Tag SuspendScrobbles `json:"scrobbles"`
	}{Tag: SuspendScrobbles(s)})
}

func (s *Session) MarshalJSON() ([]byte, error) {
	return json.Marshal(s)
}

type Name struct {
	XMLName xml.Name
}

type Token struct {
	XMLName xml.Name `xml:"token" json:"-"`
	Val     string   `xml:",innerxml" json:"token"`
}

type LFMResponse struct {
	XMLName  xml.Name `xml:"lfm" json:"-"`
	Status   string   `xml:"status,attr" json:"-"`
	Response ApiResponse
}

type Attrs struct {
	Accepted int `xml:"accepted,attr" json:"accepted"`
	Ignored  int `xml:"ignored,attr" json:"ignored"`
}

type Scrobbles struct {
	XMLName   xml.Name   `xml:"scrobbles" json:"-"`
	Scrobbles []Scrobble `xml:"scrobble" json:"scrobble"`
	Attrs     `json:"@attr"`
}

type Correctable struct {
	Name      string `xml:",chardata" json:"#text"`
	Corrected int    `xml:"corrected,attr" json:"corrected"`
}

func (field Correctable) Value() (driver.Value, error) {
	return field.Name, nil
}

func NewCorrectable(name string) Correctable {
	return Correctable{
		Name: name,
	}
}

func (field Correctable) String() string {
	return field.Name
}

func (n Name) getName() string {
	return n.XMLName.Local
}

func (store *SqlStore) AuthGetToken(r *http.Request) ApiResponse {
	token := Token{Val: randomToken(16)}
	return token
}

func (store *SqlStore) AuthGetMobileSession(r *http.Request) ApiResponse {
	return struct{}{}
}

func (store *SqlStore) AuthGetSession(r *http.Request) ApiResponse {
	var response struct {
		Session *Session `json:"session"`
	}
	session := &Session{
		User:     "thibauthorel",
		Client:   r.FormValue("api_key"),
		Protocol: "2.0",
		Key:      randomToken(16),
	}
	store.PutSession(session)
	response.Session = session
	return response
}

func (store *SqlStore) TrackScrobble(r *http.Request) (ApiResponse, error) {
	if session, err := store.GetSession(r.FormValue("sk")); err != nil {
		fmt.Printf("%v\n", err)
		return struct{}{}, err
	} else {
		scrobbles, ignored := parseScrobbles(r.Form, session)
		store.PutScrobbles(scrobbles)
		return Scrobbles{Scrobbles: scrobbles,
			Attrs: Attrs{len(scrobbles), ignored}}, nil
	}
}

func (app *App) ApiHandler(w http.ResponseWriter, r *http.Request) {
	method := r.FormValue("method")
	var response ApiResponse
	switch strings.ToLower(method) {
	case "auth.gettoken":
		response = app.AuthGetToken(r)
	case "auth.getsession":
		response = app.AuthGetSession(r)
	case "auth.getmobilesession":
		response = app.AuthGetSession(r)
	case "track.scrobble":
		if r, err := app.DataStore.TrackScrobble(r); err != nil {
			fmt.Printf("%v\n", err)
		} else {
			response = r
		}
	}
	var text []byte
	switch r.FormValue("format") {
	case "json":
		text, _ = json.Marshal(response)
	default:
		xmlresponse := LFMResponse{Status: "ok",
			Response: response}
		text, _ = xml.Marshal(xmlresponse)
		fmt.Fprint(w, xml.Header)
	}
	fmt.Printf("%s\n", text)
	w.Write(text)
}