//
//  rhimportd
//
//  The Radio Helsinki Rivendell Import Daemon
//
//
//  Copyright (C) 2015 Christian Pointner <equinox@helsinki.at>
//
//  This file is part of rhimportd.
//
//  rhimportd is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  any later version.
//
//  rhimportd is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with rhimportd. If not, see <http://www.gnu.org/licenses/>.
//

package rhimport

import (
	"bufio"
	"bytes"
	"fmt"
	"github.com/golang-basic/go-curl"
	"mime/multipart"
	"net/http"
	"os"
	"path"
)

var (
	bool2str = map[bool]string{false: "0", true: "1"}
)

type ImportContext struct {
	*Config
	*RdDb
	UserName             string
	Password             string
	Trusted              bool
	ShowId               int
	ClearShowCarts       bool
	GroupName            string
	Cart                 uint
	Cut                  uint
	Channels             uint
	NormalizationLevel   int
	AutotrimLevel        int
	UseMetaData          bool
	SourceUri            string
	SourceFile           string
	DeleteSourceFile     bool
	DeleteSourceDir      bool
	ProgressCallBack     func(step int, step_name string, progress float64, userdata interface{})
	ProgressCallBackData interface{}
}

func NewImportContext(conf *Config, rddb *RdDb, user string) *ImportContext {
	ctx := new(ImportContext)
	ctx.Config = conf
	ctx.RdDb = rddb
	ctx.UserName = user
	ctx.Password = ""
	ctx.Trusted = false
	ctx.ShowId = 0
	ctx.ClearShowCarts = false
	ctx.GroupName = ""
	ctx.Cart = 0
	ctx.Cut = 0
	ctx.Channels = 2
	ctx.NormalizationLevel = -12
	ctx.AutotrimLevel = 0
	ctx.UseMetaData = false
	ctx.SourceFile = ""
	ctx.DeleteSourceFile = false
	ctx.DeleteSourceDir = false
	ctx.ProgressCallBack = nil

	return ctx
}

func (ctx *ImportContext) SanityCheck() error {
	if ctx.UserName == "" {
		return fmt.Errorf("empty Username is not allowed")
	}
	if ctx.Password == "" && !ctx.Trusted {
		return fmt.Errorf("empty Password on untrusted control interface is not allowed")
	}
	if ctx.ShowId != 0 {
		return nil
	}
	if ctx.GroupName != "" {
		ismusic, err := ctx.checkMusicGroup()
		if err != nil {
			return err
		}
		if !ismusic {
			return fmt.Errorf("supplied GroupName is not a music pool")
		}
		return nil
	}
	if ctx.Cart == 0 {
		return fmt.Errorf("either ShowId, PoolName or CartNumber must be supplied")
	}
	if ctx.Channels != 1 && ctx.Channels != 2 {
		return fmt.Errorf("channles must be 1 or 2")
	}
	return nil
}

func (ctx *ImportContext) getPassword(cached bool) (err error) {
	req := getPasswordRequest{}
	req.username = ctx.UserName
	req.cached = cached
	req.response = make(chan getPasswordResult)
	ctx.RdDb.getPasswordChan <- req

	res := <-req.response
	if res.err != nil {
		return res.err
	}
	ctx.Password = res.password
	return nil
}

func (ctx *ImportContext) getGroupOfCart() error {
	req := getGroupOfCartRequest{}
	req.cart = ctx.Cart
	req.response = make(chan getGroupOfCartResult)
	ctx.RdDb.getGroupOfCartChan <- req

	res := <-req.response
	if res.err != nil {
		return res.err
	}
	ctx.GroupName = res.group
	return nil
}

func (ctx *ImportContext) getShowInfo() (err error) {
	req := getShowInfoRequest{}
	req.showid = ctx.ShowId
	req.response = make(chan getShowInfoResult)
	ctx.RdDb.getShowInfoChan <- req

	res := <-req.response
	if res.err != nil {
		err = res.err
		return
	}

	rhdl.Printf("Show %d:\n", ctx.ShowId)
	rhdl.Printf("  Title: '%s'\n", res.title)
	rhdl.Printf("  Normalization Level: %d\n", res.norm_lvl)
	rhdl.Printf("  Autotrim Level: %d\n", res.trim_lvl)
	rhdl.Printf("  Carts: %v\n", res.carts)
	return
}

func (ctx *ImportContext) checkMusicGroup() (bool, error) {
	req := checkMusicGroupRequest{}
	req.group = ctx.GroupName
	req.response = make(chan checkMusicGroupResult)
	ctx.RdDb.checkMusicGroupChan <- req

	res := <-req.response
	if res.err != nil {
		return false, res.err
	}
	return res.ismusic, nil
}

func (ctx *ImportContext) getMusicInfo() (err error) {
	req := getMusicInfoRequest{}
	req.group = ctx.GroupName
	req.response = make(chan getMusicInfoResult)
	ctx.RdDb.getMusicInfoChan <- req

	res := <-req.response
	if res.err != nil {
		return res.err
	}
	ctx.NormalizationLevel = res.norm_lvl
	ctx.AutotrimLevel = res.trim_lvl
	return
}

type ImportResult struct {
	ResponseCode int
	ErrorString  string
	Cart         uint
	Cut          uint
}

func (self *ImportResult) fromRDWebResult(rdres *RDWebResult) {
	self.ResponseCode = rdres.ResponseCode
	self.ErrorString = rdres.ErrorString
	if rdres.AudioConvertError != 0 {
		self.ErrorString += fmt.Sprint(", Audio Convert Error: %d", rdres.AudioConvertError)
	}
}

func add_cart(ctx *ImportContext, result *ImportResult) (err error) {
	var b bytes.Buffer
	w := multipart.NewWriter(&b)

	if err = w.WriteField("COMMAND", "12"); err != nil {
		return
	}
	if err = w.WriteField("LOGIN_NAME", ctx.UserName); err != nil {
		return
	}
	if err = w.WriteField("PASSWORD", ctx.Password); err != nil {
		return
	}
	if err = w.WriteField("GRPOUP_NAME", ctx.GroupName); err != nil {
		return
	}
	if err = w.WriteField("TYPE", "audio"); err != nil {
		return
	}
	if ctx.Cart != 0 {
		if err = w.WriteField("CART_NUMBER", fmt.Sprintf("%d", ctx.Cart)); err != nil {
			return
		}
	}
	w.Close()

	var res *http.Response
	if res, err = send_post_request(ctx.Config.RDXportEndpoint, &b, w.FormDataContentType()); err != nil {
		return
	}
	defer res.Body.Close()

	if res.StatusCode != http.StatusOK {
		var rdres *RDWebResult
		if rdres, err = NewRDWebResultFromXML(res.Body); err != nil {
			return
		}
		result.fromRDWebResult(rdres)
		return
	}
	var cartadd *RDCartAdd
	if cartadd, err = NewRDCartAddFromXML(res.Body); err != nil {
		return
	}
	result.ResponseCode = res.StatusCode
	result.ErrorString = "OK"
	result.Cart = cartadd.Carts[0].Number
	ctx.Cart = result.Cart
	return
}

func add_cut(ctx *ImportContext, result *ImportResult) (err error) {
	var b bytes.Buffer
	w := multipart.NewWriter(&b)

	if err = w.WriteField("COMMAND", "10"); err != nil {
		return
	}
	if err = w.WriteField("LOGIN_NAME", ctx.UserName); err != nil {
		return
	}
	if err = w.WriteField("PASSWORD", ctx.Password); err != nil {
		return
	}
	if err = w.WriteField("CART_NUMBER", fmt.Sprintf("%d", ctx.Cart)); err != nil {
		return
	}
	w.Close()

	var res *http.Response
	if res, err = send_post_request(ctx.Config.RDXportEndpoint, &b, w.FormDataContentType()); err != nil {
		return
	}
	defer res.Body.Close()

	if res.StatusCode != http.StatusOK {
		var rdres *RDWebResult
		if rdres, err = NewRDWebResultFromXML(res.Body); err != nil {
			return
		}
		result.fromRDWebResult(rdres)
		return
	}
	var cutadd *RDCutAdd
	if cutadd, err = NewRDCutAddFromXML(res.Body); err != nil {
		return
	}
	result.ResponseCode = res.StatusCode
	result.ErrorString = "OK"
	result.Cut = cutadd.Cuts[0].Number
	ctx.Cut = cutadd.Cuts[0].Number
	return
}

func remove_cart(ctx *ImportContext, result *ImportResult) (err error) {
	var b bytes.Buffer
	w := multipart.NewWriter(&b)

	if err = w.WriteField("COMMAND", "13"); err != nil {
		return
	}
	if err = w.WriteField("LOGIN_NAME", ctx.UserName); err != nil {
		return
	}
	if err = w.WriteField("PASSWORD", ctx.Password); err != nil {
		return
	}
	if err = w.WriteField("CART_NUMBER", fmt.Sprintf("%d", ctx.Cart)); err != nil {
		return
	}
	w.Close()

	var res *http.Response
	if res, err = send_post_request(ctx.Config.RDXportEndpoint, &b, w.FormDataContentType()); err != nil {
		return
	}
	defer res.Body.Close()

	var rdres *RDWebResult
	if rdres, err = NewRDWebResultFromXML(res.Body); err != nil {
		return
	}
	result.fromRDWebResult(rdres)
	return
}

func send_post_request(url string, b *bytes.Buffer, contenttype string) (res *http.Response, err error) {
	var req *http.Request
	if req, err = http.NewRequest("POST", url, b); err != nil {
		return
	}
	if contenttype != "" {
		req.Header.Set("Content-Type", contenttype)
	}

	client := &http.Client{}
	if res, err = client.Do(req); err != nil {
		return
	}
	return
}

func import_audio_create_request(ctx *ImportContext, easy *curl.CURL) (form *curl.Form, err error) {
	form = curl.NewForm()

	if err = form.Add("COMMAND", "2"); err != nil {
		return
	}
	if err = form.Add("LOGIN_NAME", ctx.UserName); err != nil {
		return
	}
	if err = form.Add("PASSWORD", ctx.Password); err != nil {
		return
	}
	if err = form.Add("CART_NUMBER", fmt.Sprintf("%d", ctx.Cart)); err != nil {
		return
	}
	if err = form.Add("CUT_NUMBER", fmt.Sprintf("%d", ctx.Cut)); err != nil {
		return
	}
	if err = form.Add("CHANNELS", fmt.Sprintf("%d", ctx.Channels)); err != nil {
		return
	}
	if err = form.Add("NORMALIZATION_LEVEL", fmt.Sprintf("%d", ctx.NormalizationLevel)); err != nil {
		return
	}
	if err = form.Add("AUTOTRIM_LEVEL", fmt.Sprintf("%d", ctx.AutotrimLevel)); err != nil {
		return
	}
	if err = form.Add("USE_METADATA", bool2str[ctx.UseMetaData]); err != nil {
		return
	}
	if err = form.AddFile("FILENAME", ctx.SourceFile); err != nil {
		return
	}

	return
}

func import_audio(ctx *ImportContext, result *ImportResult) (err error) {
	easy := curl.EasyInit()

	if easy != nil {
		defer easy.Cleanup()

		easy.Setopt(curl.OPT_URL, ctx.Config.RDXportEndpoint)
		easy.Setopt(curl.OPT_POST, true)

		var form *curl.Form
		if form, err = import_audio_create_request(ctx, easy); err != nil {
			return
		}
		easy.Setopt(curl.OPT_HTTPPOST, form)
		easy.Setopt(curl.OPT_HTTPHEADER, []string{"Expect:"})

		var resbody bytes.Buffer
		easy.Setopt(curl.OPT_WRITEFUNCTION, func(ptr []byte, userdata interface{}) bool {
			b := userdata.(*bytes.Buffer)
			b.Write(ptr)
			return true
		})
		easy.Setopt(curl.OPT_WRITEDATA, &resbody)

		easy.Setopt(curl.OPT_NOPROGRESS, false)
		easy.Setopt(curl.OPT_PROGRESSFUNCTION, func(dltotal, dlnow, ultotal, ulnow float64, userdata interface{}) bool {
			ctx := userdata.(*ImportContext)
			if ctx.ProgressCallBack != nil {
				ctx.ProgressCallBack(2, "importing", ulnow/ultotal, ctx.ProgressCallBackData)
			}
			return true
		})
		easy.Setopt(curl.OPT_PROGRESSDATA, ctx)

		if err = easy.Perform(); err != nil {
			err = fmt.Errorf("importer: %s", err)
			return
		}

		var rdres *RDWebResult
		if rdres, err = NewRDWebResultFromXML(bufio.NewReader(&resbody)); err != nil {
			return
		}
		result.fromRDWebResult(rdres)
		return
	} else {
		err = fmt.Errorf("Error initializing libcurl")
	}

	return
}

func cleanup_files(ctx *ImportContext) {
	if ctx.DeleteSourceFile {
		rhdl.Printf("importer: removing file: %s", ctx.SourceFile)
		if err := os.Remove(ctx.SourceFile); err != nil {
			rhl.Printf("importer: error removing source file: %s", err)
			return
		}
		if ctx.DeleteSourceDir {
			dir := path.Dir(ctx.SourceFile)
			rhdl.Printf("importer: also removing directory: %s", dir)
			if err := os.Remove(dir); err != nil {
				rhl.Printf("importer: error removing source directory: %s", err)
			}
		}
	}
	return
}

func ImportFile(ctx *ImportContext) (res *ImportResult, err error) {
	rhl.Println("ImportFile called for", ctx.SourceFile)
	defer cleanup_files(ctx)

	if ctx.ProgressCallBack != nil {
		ctx.ProgressCallBack(2, "importing", 0.0, ctx.ProgressCallBackData)
	}

	if ctx.Trusted {
		if err = ctx.getPassword(true); err != nil {
			return
		}
	}

	res = &ImportResult{}
	if ctx.ShowId != 0 {
		res.ResponseCode = 500
		res.ErrorString = "Importing to shows using the show-id is not yet implemented"
		// TODO: fetch info from dropboxes (cartlist, groupname, import-params)
		//     - if (ctx.Cart not in cartlist) -> Error
		//     - if (ClearShowCarts == true): foreach(cart in cartlist): remove_cart(cart) [200 || 404 -> OK]
		//     - add_cart(ctx, res) [200 -> OK]
		//     - add_cut(ctx, res) [200 -> OK]
		return
	} else if ctx.GroupName != "" {
		res.ResponseCode = 500
		res.ErrorString = "Importing to music pools is not yet implemented"
		// TODO: fetch info from dropboxes (import-params)
		//     - add_cart(ctx, res) [200 -> OK]
		//     - add_cut(ctx, res) [200 -> OK]
		return
	} else if ctx.Cart != 0 && ctx.Cut == 0 {
		res.ResponseCode = 500
		res.ErrorString = "Importing to a Cart which might not exist is not yet implemented"
		// TODO: (everything except Cut, GroupName and ShowId must be in context)
		//     - ctx.getGroupOfCart(ctx.Cart)
		//     - remove_cart(ctx, res) [200 || 404 -> OK]
		//     - add_cart(ctx, res) [200 -> OK]
		//     - add_cut(ctx, res) [200 -> OK]
		return
	}

	if ctx.Cart != 0 && ctx.Cut != 0 {
		if err = import_audio(ctx, res); err != nil {
			return
		}
		res.Cart = ctx.Cart
		res.Cut = ctx.Cut
	} else {
		res.ResponseCode = http.StatusBadRequest
		res.ErrorString = "The request doesn't contain enough information to be processed"
	}

	rhdl.Printf("ImportResult: %+v\n", res)

	if res.ResponseCode == http.StatusOK {
		rhl.Println("ImportFile succesfully imported", ctx.SourceFile)
	} else {
		rhl.Println("ImportFile import of", ctx.SourceFile, "was unsuccesful")
	}
	return
}