package eu.kanade.tachiyomi.data.track.myanimelist

import android.net.Uri
import eu.kanade.tachiyomi.data.database.models.Track
import eu.kanade.tachiyomi.data.track.TrackManager
import eu.kanade.tachiyomi.data.track.model.TrackSearch
import eu.kanade.tachiyomi.network.GET
import eu.kanade.tachiyomi.network.POST
import eu.kanade.tachiyomi.network.asObservable
import eu.kanade.tachiyomi.network.asObservableSuccess
import eu.kanade.tachiyomi.util.lang.toCalendar
import eu.kanade.tachiyomi.util.selectInt
import eu.kanade.tachiyomi.util.selectText
import java.io.BufferedReader
import java.io.InputStreamReader
import java.text.SimpleDateFormat
import java.util.Calendar
import java.util.GregorianCalendar
import java.util.Locale
import java.util.zip.GZIPInputStream
import okhttp3.FormBody
import okhttp3.MediaType.Companion.toMediaTypeOrNull
import okhttp3.OkHttpClient
import okhttp3.RequestBody
import okhttp3.RequestBody.Companion.toRequestBody
import okhttp3.Response
import org.json.JSONObject
import org.jsoup.Jsoup
import org.jsoup.nodes.Document
import org.jsoup.nodes.Element
import org.jsoup.parser.Parser
import rx.Observable

class MyAnimeListApi(private val client: OkHttpClient, interceptor: MyAnimeListInterceptor) {

    private val authClient = client.newBuilder().addInterceptor(interceptor).build()

    fun search(query: String): Observable<List<TrackSearch>> {
        return if (query.startsWith(PREFIX_MY)) {
            val realQuery = query.removePrefix(PREFIX_MY)
            getList()
                .flatMap { Observable.from(it) }
                .filter { it.title.contains(realQuery, true) }
                .toList()
        } else {
            client.newCall(GET(searchUrl(query)))
                .asObservable()
                .flatMap { response ->
                    Observable.from(
                        Jsoup.parse(response.consumeBody())
                            .select("div.js-categories-seasonal.js-block-list.list")
                            .select("table").select("tbody")
                            .select("tr").drop(1)
                    )
                }
                .filter { row ->
                    row.select(TD)[2].text() != "Novel"
                }
                .map { row ->
                    TrackSearch.create(TrackManager.MYANIMELIST).apply {
                        title = row.searchTitle()
                        media_id = row.searchMediaId()
                        total_chapters = row.searchTotalChapters()
                        summary = row.searchSummary()
                        cover_url = row.searchCoverUrl()
                        tracking_url = mangaUrl(media_id)
                        publishing_status = row.searchPublishingStatus()
                        publishing_type = row.searchPublishingType()
                        start_date = row.searchStartDate()
                    }
                }
                .toList()
        }
    }

    fun addLibManga(track: Track): Observable<Track> {
        return Observable.defer {
            authClient.newCall(POST(url = addUrl(), body = mangaPostPayload(track)))
                .asObservableSuccess()
                .map { track }
        }
    }

    fun updateLibManga(track: Track): Observable<Track> {
        return Observable.defer {
            // Get track data
            val response = authClient.newCall(GET(url = editPageUrl(track.media_id))).execute()
            val editData = response.use {
                val page = Jsoup.parse(it.consumeBody())

                // Extract track data from MAL page
                extractDataFromEditPage(page).apply {
                    // Apply changes to the just fetched data
                    copyPersonalFrom(track)
                }
            }

            // Update remote
            authClient.newCall(POST(url = editPageUrl(track.media_id), body = mangaEditPostBody(editData)))
                .asObservableSuccess()
                .map {
                    track
                }
        }
    }

    fun findLibManga(track: Track): Observable<Track?> {
        return authClient.newCall(GET(url = editPageUrl(track.media_id)))
            .asObservable()
            .map { response ->
                var libTrack: Track? = null
                response.use {
                    if (it.priorResponse?.isRedirect != true) {
                        val trackForm = Jsoup.parse(it.consumeBody())

                        libTrack = Track.create(TrackManager.MYANIMELIST).apply {
                            last_chapter_read = trackForm.select("#add_manga_num_read_chapters").`val`().toInt()
                            total_chapters = trackForm.select("#totalChap").text().toInt()
                            status = trackForm.select("#add_manga_status > option[selected]").`val`().toInt()
                            score = trackForm.select("#add_manga_score > option[selected]").`val`().toFloatOrNull()
                                ?: 0f
                            started_reading_date = trackForm.searchDatePicker("#add_manga_start_date")
                            finished_reading_date = trackForm.searchDatePicker("#add_manga_finish_date")
                        }
                    }
                }
                libTrack
            }
    }

    fun getLibManga(track: Track): Observable<Track> {
        return findLibManga(track)
            .map { it ?: throw Exception("Could not find manga") }
    }

    fun login(username: String, password: String): String {
        val csrf = getSessionInfo()

        login(username, password, csrf)

        return csrf
    }

    private fun getSessionInfo(): String {
        val response = client.newCall(GET(loginUrl())).execute()

        return Jsoup.parse(response.consumeBody())
            .select("meta[name=csrf_token]")
            .attr("content")
    }

    private fun login(username: String, password: String, csrf: String) {
        val response = client.newCall(POST(url = loginUrl(), body = loginPostBody(username, password, csrf))).execute()

        response.use {
            if (response.priorResponse?.code != 302) throw Exception("Authentication error")
        }
    }

    private fun getList(): Observable<List<TrackSearch>> {
        return getListUrl()
            .flatMap { url ->
                getListXml(url)
            }
            .flatMap { doc ->
                Observable.from(doc.select("manga"))
            }
            .map {
                TrackSearch.create(TrackManager.MYANIMELIST).apply {
                    title = it.selectText("manga_title")!!
                    media_id = it.selectInt("manga_mangadb_id")
                    last_chapter_read = it.selectInt("my_read_chapters")
                    status = getStatus(it.selectText("my_status")!!)
                    score = it.selectInt("my_score").toFloat()
                    total_chapters = it.selectInt("manga_chapters")
                    tracking_url = mangaUrl(media_id)
                    started_reading_date = it.searchDateXml("my_start_date")
                    finished_reading_date = it.searchDateXml("my_finish_date")
                }
            }
            .toList()
    }

    private fun getListUrl(): Observable<String> {
        return authClient.newCall(POST(url = exportListUrl(), body = exportPostBody()))
            .asObservable()
            .map { response ->
                baseUrl + Jsoup.parse(response.consumeBody())
                    .select("div.goodresult")
                    .select("a")
                    .attr("href")
            }
    }

    private fun getListXml(url: String): Observable<Document> {
        return authClient.newCall(GET(url))
            .asObservable()
            .map { response ->
                Jsoup.parse(response.consumeXmlBody(), "", Parser.xmlParser())
            }
    }

    private fun Response.consumeBody(): String? {
        use {
            if (it.code != 200) throw Exception("HTTP error ${it.code}")
            return it.body?.string()
        }
    }

    private fun Response.consumeXmlBody(): String? {
        use { res ->
            if (res.code != 200) throw Exception("Export list error")
            BufferedReader(InputStreamReader(GZIPInputStream(res.body?.source()?.inputStream()))).use { reader ->
                val sb = StringBuilder()
                reader.forEachLine { line ->
                    sb.append(line)
                }
                return sb.toString()
            }
        }
    }

    private fun extractDataFromEditPage(page: Document): MyAnimeListEditData {
        val tables = page.select("form#main-form table")

        return MyAnimeListEditData(
            entry_id = tables[0].select("input[name=entry_id]").`val`(), // Always 0
            manga_id = tables[0].select("#manga_id").`val`(),
            status = tables[0].select("#add_manga_status > option[selected]").`val`(),
            num_read_volumes = tables[0].select("#add_manga_num_read_volumes").`val`(),
            last_completed_vol = tables[0].select("input[name=last_completed_vol]").`val`(), // Always empty
            num_read_chapters = tables[0].select("#add_manga_num_read_chapters").`val`(),
            score = tables[0].select("#add_manga_score > option[selected]").`val`(),
            start_date_month = tables[0].select("#add_manga_start_date_month > option[selected]").`val`(),
            start_date_day = tables[0].select("#add_manga_start_date_day > option[selected]").`val`(),
            start_date_year = tables[0].select("#add_manga_start_date_year > option[selected]").`val`(),
            finish_date_month = tables[0].select("#add_manga_finish_date_month > option[selected]").`val`(),
            finish_date_day = tables[0].select("#add_manga_finish_date_day > option[selected]").`val`(),
            finish_date_year = tables[0].select("#add_manga_finish_date_year > option[selected]").`val`(),
            tags = tables[1].select("#add_manga_tags").`val`(),
            priority = tables[1].select("#add_manga_priority > option[selected]").`val`(),
            storage_type = tables[1].select("#add_manga_storage_type > option[selected]").`val`(),
            num_retail_volumes = tables[1].select("#add_manga_num_retail_volumes").`val`(),
            num_read_times = tables[1].select("#add_manga_num_read_times").`val`(),
            reread_value = tables[1].select("#add_manga_reread_value > option[selected]").`val`(),
            comments = tables[1].select("#add_manga_comments").`val`(),
            is_asked_to_discuss = tables[1].select("#add_manga_is_asked_to_discuss > option[selected]").`val`(),
            sns_post_type = tables[1].select("#add_manga_sns_post_type > option[selected]").`val`()
        )
    }

    companion object {
        const val CSRF = "csrf_token"

        private const val baseUrl = "https://myanimelist.net"
        private const val baseMangaUrl = "$baseUrl/manga/"
        private const val baseModifyListUrl = "$baseUrl/ownlist/manga"
        private const val PREFIX_MY = "my:"
        private const val TD = "td"

        private fun mangaUrl(remoteId: Int) = baseMangaUrl + remoteId

        private fun loginUrl() = Uri.parse(baseUrl).buildUpon()
            .appendPath("login.php")
            .toString()

        private fun searchUrl(query: String): String {
            val col = "c[]"
            return Uri.parse(baseUrl).buildUpon()
                .appendPath("manga.php")
                .appendQueryParameter("q", query)
                .appendQueryParameter(col, "a")
                .appendQueryParameter(col, "b")
                .appendQueryParameter(col, "c")
                .appendQueryParameter(col, "d")
                .appendQueryParameter(col, "e")
                .appendQueryParameter(col, "g")
                .toString()
        }

        private fun exportListUrl() = Uri.parse(baseUrl).buildUpon()
            .appendPath("panel.php")
            .appendQueryParameter("go", "export")
            .toString()

        private fun editPageUrl(mediaId: Int) = Uri.parse(baseModifyListUrl).buildUpon()
            .appendPath(mediaId.toString())
            .appendPath("edit")
            .toString()

        private fun addUrl() = Uri.parse(baseModifyListUrl).buildUpon()
            .appendPath("add.json")
            .toString()

        private fun loginPostBody(username: String, password: String, csrf: String): RequestBody {
            return FormBody.Builder()
                .add("user_name", username)
                .add("password", password)
                .add("cookie", "1")
                .add("sublogin", "Login")
                .add("submit", "1")
                .add(CSRF, csrf)
                .build()
        }

        private fun exportPostBody(): RequestBody {
            return FormBody.Builder()
                .add("type", "2")
                .add("subexport", "Export My List")
                .build()
        }

        private fun mangaPostPayload(track: Track): RequestBody {
            val body = JSONObject()
                .put("manga_id", track.media_id)
                .put("status", track.status)
                .put("score", track.score)
                .put("num_read_chapters", track.last_chapter_read)

            return body.toString().toRequestBody("application/json; charset=utf-8".toMediaTypeOrNull())
        }

        private fun mangaEditPostBody(track: MyAnimeListEditData): RequestBody {
            return FormBody.Builder()
                .add("entry_id", track.entry_id)
                .add("manga_id", track.manga_id)
                .add("add_manga[status]", track.status)
                .add("add_manga[num_read_volumes]", track.num_read_volumes)
                .add("last_completed_vol", track.last_completed_vol)
                .add("add_manga[num_read_chapters]", track.num_read_chapters)
                .add("add_manga[score]", track.score)
                .add("add_manga[start_date][month]", track.start_date_month)
                .add("add_manga[start_date][day]", track.start_date_day)
                .add("add_manga[start_date][year]", track.start_date_year)
                .add("add_manga[finish_date][month]", track.finish_date_month)
                .add("add_manga[finish_date][day]", track.finish_date_day)
                .add("add_manga[finish_date][year]", track.finish_date_year)
                .add("add_manga[tags]", track.tags)
                .add("add_manga[priority]", track.priority)
                .add("add_manga[storage_type]", track.storage_type)
                .add("add_manga[num_retail_volumes]", track.num_retail_volumes)
                .add("add_manga[num_read_times]", track.num_read_times)
                .add("add_manga[reread_value]", track.reread_value)
                .add("add_manga[comments]", track.comments)
                .add("add_manga[is_asked_to_discuss]", track.is_asked_to_discuss)
                .add("add_manga[sns_post_type]", track.sns_post_type)
                .add("submitIt", track.submitIt)
                .build()
        }

        private fun Element.searchDateXml(field: String): Long {
            val text = selectText(field, "0000-00-00")!!
            // MAL sets the data to 0000-00-00 when date is invalid or missing
            if (text == "0000-00-00") {
                return 0L
            }

            return SimpleDateFormat("yyyy-MM-dd", Locale.US).parse(text)?.time ?: 0L
        }

        private fun Element.searchDatePicker(id: String): Long {
            val month = select(id + "_month > option[selected]").`val`().toIntOrNull()
            val day = select(id + "_day > option[selected]").`val`().toIntOrNull()
            val year = select(id + "_year > option[selected]").`val`().toIntOrNull()
            if (year == null || month == null || day == null) {
                return 0L
            }

            return GregorianCalendar(year, month - 1, day).timeInMillis
        }

        private fun Element.searchTitle() = select("strong").text()!!

        private fun Element.searchTotalChapters() = if (select(TD)[4].text() == "-") 0 else select(TD)[4].text().toInt()

        private fun Element.searchCoverUrl() = select("img")
            .attr("data-src")
            .split("\\?")[0]
            .replace("/r/50x70/", "/")

        private fun Element.searchMediaId() = select("div.picSurround")
            .select("a").attr("id")
            .replace("sarea", "")
            .toInt()

        private fun Element.searchSummary() = select("div.pt4")
            .first()
            .ownText()!!

        private fun Element.searchPublishingStatus() = if (select(TD).last().text() == "-") "Publishing" else "Finished"

        private fun Element.searchPublishingType() = select(TD)[2].text()!!

        private fun Element.searchStartDate() = select(TD)[6].text()!!

        private fun getStatus(status: String) = when (status) {
            "Reading" -> 1
            "Completed" -> 2
            "On-Hold" -> 3
            "Dropped" -> 4
            "Plan to Read" -> 6
            else -> 1
        }
    }

    private class MyAnimeListEditData(
        // entry_id
        var entry_id: String,

        // manga_id
        var manga_id: String,

        // add_manga[status]
        var status: String,

        // add_manga[num_read_volumes]
        var num_read_volumes: String,

        // last_completed_vol
        var last_completed_vol: String,

        // add_manga[num_read_chapters]
        var num_read_chapters: String,

        // add_manga[score]
        var score: String,

        // add_manga[start_date][month]
        var start_date_month: String, // [1-12]

        // add_manga[start_date][day]
        var start_date_day: String,

        // add_manga[start_date][year]
        var start_date_year: String,

        // add_manga[finish_date][month]
        var finish_date_month: String, // [1-12]

        // add_manga[finish_date][day]
        var finish_date_day: String,

        // add_manga[finish_date][year]
        var finish_date_year: String,

        // add_manga[tags]
        var tags: String,

        // add_manga[priority]
        var priority: String,

        // add_manga[storage_type]
        var storage_type: String,

        // add_manga[num_retail_volumes]
        var num_retail_volumes: String,

        // add_manga[num_read_times]
        var num_read_times: String,

        // add_manga[reread_value]
        var reread_value: String,

        // add_manga[comments]
        var comments: String,

        // add_manga[is_asked_to_discuss]
        var is_asked_to_discuss: String,

        // add_manga[sns_post_type]
        var sns_post_type: String,

        // submitIt
        val submitIt: String = "0"
    ) {
        fun copyPersonalFrom(track: Track) {
            num_read_chapters = track.last_chapter_read.toString()
            val numScore = track.score.toInt()
            if (numScore in 1..9) {
                score = numScore.toString()
            }
            status = track.status.toString()
            if (track.started_reading_date == 0L) {
                start_date_month = ""
                start_date_day = ""
                start_date_year = ""
            }
            if (track.finished_reading_date == 0L) {
                finish_date_month = ""
                finish_date_day = ""
                finish_date_year = ""
            }
            track.started_reading_date.toCalendar()?.let { cal ->
                start_date_month = (cal[Calendar.MONTH] + 1).toString()
                start_date_day = cal[Calendar.DAY_OF_MONTH].toString()
                start_date_year = cal[Calendar.YEAR].toString()
            }
            track.finished_reading_date.toCalendar()?.let { cal ->
                finish_date_month = (cal[Calendar.MONTH] + 1).toString()
                finish_date_day = cal[Calendar.DAY_OF_MONTH].toString()
                finish_date_year = cal[Calendar.YEAR].toString()
            }
        }
    }
}