index/src/main/kotlin/moe/odango/index/scraper/mal/AnimePageScraper.kt

package moe.odango.index.scraper.mal

import moe.odango.index.entity.AnimeRelation
import moe.odango.index.entity.MyAnimeListInfo
import moe.odango.index.utils.IntDate
import moe.odango.index.utils.ProducerFunction
import moe.odango.index.utils.brText
import org.jsoup.Jsoup
import org.jsoup.nodes.Element
import java.time.Duration
import java.util.*

class AnimePageScraper(body: String) {
    private val dom = Jsoup.parse(body)

    private val items: MutableMap<String, Pair<String, Element>> = mutableMapOf()

    data class Info(
        val title: String,
        val englishName: String?,
        val japaneseName: String?,
        val synonyms: List<String>,
        val description: String,
        val type: MyAnimeListInfo.ReleaseType,
        val episodes: Int?,
        val source: String?,
        val image: String?,
        val genres: List<Genre>,
        val aired: Aired?,
        val premiered: Premiered?,
        val rating: MyAnimeListInfo.Rating?,
        val duration: Duration?,
        val related: List<Relation>,
        val producers: List<ProducerRelation>
    )

    fun getInfo() = Info(
        getTitle(),
        getEnglishName(),
        getJapaneseName(),
        getSynonyms(),
        getDescription(),
        getReleaseType(),
        getEpisodes(),
        getSource(),
        getImage(),
        getGenres(),
        getAired(),
        getPremiered(),
        getRating(),
        getDuration(),
        getRelated(),
        getProducers()
    )

    fun getEpisodes(): Int? {
        return items["episodes"]?.first?.toIntOrNull()
    }

    fun getReleaseType(): MyAnimeListInfo.ReleaseType {
        return MyAnimeListInfo.ReleaseType.valueOf(items["type"]!!.first)
    }

    fun getTitle(): String {
        return dom.select(".h1-title span[itemprop=name]").first().brText().split("\n").first()
    }

    fun getSynonyms(): List<String> {
        // If the english name or title contains a comma we can't parse synonyms since they're splice by comma's
        return if (getEnglishName()?.contains(",") == true || getTitle().contains(",")) listOf() else items["synonyms"]?.first?.split(
            ","
        )?.map { it.trim() } ?: listOf()
    }

    fun getJapaneseName(): String? {
        return items["japanese"]?.first
    }

    fun getEnglishName(): String? {
        return items["english"]?.first
    }

    init {
        val after = dom
            .select(".dark_text")
            .parents()

        for (item in after) {
            val parts = item.text().split(":", limit = 2)
            val key = parts.first().trim().toLowerCase()
            val value = parts.last().trim()
            items[key] = value to item
        }
    }

    fun getSource(): String? {
        return items["source"]?.first
    }

    fun getImage(): String? {
        return dom.selectFirst("img[itemprop=image]")?.attr("data-src")
    }

    fun getDescription(): String {
        return dom.selectFirst("[itemprop=description]")?.brText() ?: ""
    }

    fun getAired(): Aired? {
        return items["aired"]?.let {
            val (from, to) = it.first.split(" to ", limit = 2)
                .let { part -> part.first() to part.getOrNull(1) }

            return Aired(IntDate.parse("MMM d, yyyy", from, Locale.US) ?: return null, to?.let { dateStr ->
                IntDate.parse("MMM d, yyyy", dateStr, Locale.US)
            })
        }
    }

    data class Aired(val start: IntDate, val end: IntDate? = null)

    fun getPremiered(): Premiered? {
        val (season, year) = items["premiered"]
            ?.first
            ?.split(" ", limit = 2)
            ?.takeUnless { it.size != 2 }
            ?: return null

        return Premiered(Premiered.Season.fromString(season) ?: return null, year.toIntOrNull() ?: return null)
    }

    data class Premiered(val season: Season, val year: Int) {
        enum class Season {
            Spring,
            Summer,
            Fall,
            Winter;

            companion object {
                fun fromString(season: String): Season? {
                    return when (season.toLowerCase()) {
                        "spring" -> Spring
                        "summer" -> Summer
                        "fall" -> Fall
                        "winter" -> Winter
                        else -> null
                    }
                }
            }
        }
    }

    fun getGenres(): List<Genre> {
        return items["genres"]?.second?.let {
            it.select("a").map { a ->
                val href = a.attr("href").split("/")
                Genre(href[href.indexOf("genre") + 1].toInt(), a.text().trim())
            }
        } ?: emptyList()
    }

    data class Genre(val id: Int, val name: String) {
        companion object {
            val COMEDY = Genre(4, "Comedy")
            val DEMONS = Genre(6, "Demons")
            val DRAMA = Genre(8, "Drama")
            val FANTASY = Genre(10, "Fantasy")
            val HENTAI = Genre(12, "Hentai")
            val MAGIC = Genre(16, "Magic")
            val PARODY = Genre(20, "Parody")
            val ROMANCE = Genre(22, "Romance")
            val SCHOOL = Genre(23, "School")
            val SCIFI = Genre(24, "Sci-Fi")
            val SHOUJO = Genre(25, "Shoujo")
            val HAREM = Genre(35, "Harem")
            val MILITARY = Genre(38, "Military")
        }
    }

    fun getRelated(): List<Relation> {
        return dom.select("table.anime_detail_related_anime tr").flatMap {
            val type = it.child(0).text().trim().replace(":", "")
            it.child(1).select("a").mapNotNull { el ->
                el.attr("href")
                    ?.let { href ->
                        val parts = href.split("/")

                        if (parts.contains("anime")) {
                            parts[parts.indexOf("anime") + 1].toLongOrNull()
                        } else {
                            null
                        }
                    }
                    ?.let { id -> Relation(type, id) }

            }
        }
    }

    fun getProducers(): List<ProducerRelation> {
        fun Pair<String, Element>?.getProducers(): List<Producer> {
            return this?.second?.let {
                it.select("a").mapNotNull { a ->
                    val href = a.attr("href").split("/")
                    if (href.contains("producer")) Producer(
                        href[href.indexOf("producer") + 1].toInt(),
                        a.text().trim()
                    ) else null
                }
            } ?: emptyList()
        }

        val producers = items["producers"].getProducers()
        val studios = items["studios"].getProducers()
        val licensors = items["licensors"].getProducers()

        return producers.map { ProducerRelation(ProducerFunction.Producer, it) } +
                studios.map { ProducerRelation(ProducerFunction.Studio, it) } +
                licensors.map { ProducerRelation(ProducerFunction.Licensor, it) }
    }

    data class ProducerRelation(val function: ProducerFunction, val producer: Producer)

    data class Producer(val id: Int, val name: String)

    fun getRating(): MyAnimeListInfo.Rating? {
        return MyAnimeListInfo.Rating.fromString(items["rating"]?.first?.split(" - ")?.first()?.trim() ?: return null)
    }

    private val durationRegex = Regex("(?:(\\d+) hrs.)?(?:(\\d+) min.)?")

    fun getDuration(): Duration? {
        val txt = items["duration"]?.first?.split(" per ", limit = 2)?.firstOrNull() ?: return null
        val grps = durationRegex.matchEntire(txt)?.groups ?: return null
        val hrs = grps[1]
        val min = grps[2]
        var x = Duration.ofMillis(0)
        x += Duration.ofHours(hrs?.value?.toInt() ?: 0)
        x += Duration.ofMinutes(min?.value?.toInt() ?: 0)
        return x
    }


    data class Relation(val type: AnimeRelation.RelationType, val id: Long) {
        constructor(type: String, id: Long) : this(AnimeRelation.RelationType.fromString(type), id)
    }
}