import { useContext, useState } from 'preact/hooks'
import { SolutionStat } from '../../shared/model'
import { sortByNumericKey, sortByStringKey } from '../../shared/utils'
import { prependBaseUrl } from '../../shared/utils'
import { Header } from '../components/Header'

import { useResource, MetadataContext } from '../hooks'

export const ScoresPage = () => {
    const metadata = useContext(MetadataContext)
    metadata.title = `PHC Problemi`
    metadata.description = 'Bacheca di problemi del PHC'

    const [stats] = useResource<Record<string, SolutionStat>>(`/api/stats`, {})

    type Column = 'student' | 'sent' | 'correct'
    type Order = 'ascending' | 'descending'
    type SortStateSpace = [Column, Order]

    const [[sortStateColumn, sortStateOrder], setSortState] = useState<SortStateSpace>(['correct', 'descending'])

    const transitionColumn: (k: Column) => Partial<Record<Column, Record<Order, (c: Column) => SortStateSpace>>> = k => ({
        [k]: {
            ascending: (c: Column) => (c === k ? [k, 'descending'] : [c, 'ascending']),
            descending: (c: Column) => (c === k ? [k, 'ascending'] : [c, 'ascending']),
        },
    })

    const transitionMap: Record<Column, Record<Order, (c: Column) => SortStateSpace>> = {
        ...(transitionColumn('student') as Record<'student', Record<Order, (c: Column) => SortStateSpace>>),
        ...(transitionColumn('sent') as Record<'sent', Record<Order, (c: Column) => SortStateSpace>>),
        ...(transitionColumn('correct') as Record<'correct', Record<Order, (c: Column) => SortStateSpace>>),
    }

    let orderedStats

    if (sortStateColumn === 'student') {
        orderedStats = sortByStringKey(Object.entries(stats), ([user, s]) => user.toLowerCase(), sortStateOrder === 'ascending')
    } else {
        orderedStats = sortByNumericKey(
            Object.entries(stats),
            // @ts-ignore
            ([user, s]) => s[sortStateColumn + 'SolutionsCount'],
            sortStateOrder === 'ascending'
        )
    }

    return (
        <>
            <Header />
            <main class="page-scores">
                <div class="subtitle">Classifica</div>
                {orderedStats.length > 0 ? (
                    <div class="scrollable">
                        <div class="table">
                            <div class="cell header">
                                <span>Studente</span>
                                <span onClick={() => setSortState(transitionMap[sortStateColumn][sortStateOrder]('student'))}>
                                    <span class="material-symbols-outlined icon">
                                        {sortStateColumn === 'student'
                                            ? sortStateOrder === 'ascending'
                                                ? 'expand_more'
                                                : 'expand_less'
                                            : 'unfold_more'}
                                    </span>
                                </span>
                            </div>
                            <div class="cell header">
                                <span>Soluzioni Inviate</span>
                                <span onClick={() => setSortState(transitionMap[sortStateColumn][sortStateOrder]('sent'))}>
                                    <span class="material-symbols-outlined icon">
                                        {sortStateColumn === 'sent'
                                            ? sortStateOrder === 'ascending'
                                                ? 'expand_more'
                                                : 'expand_less'
                                            : 'unfold_more'}
                                    </span>
                                </span>
                            </div>
                            <div class="cell header">
                                <span>Soluzioni Corrette</span>
                                <span onClick={() => setSortState(transitionMap[sortStateColumn][sortStateOrder]('correct'))}>
                                    <span class="material-symbols-outlined icon">
                                        {sortStateColumn === 'correct'
                                            ? sortStateOrder === 'ascending'
                                                ? 'expand_more'
                                                : 'expand_less'
                                            : 'unfold_more'}
                                    </span>
                                </span>
                            </div>
                            {orderedStats.map(([user, s]) => (
                                <>
                                    <div class="cell">
                                        <a href={prependBaseUrl(`/u/${user}`)}>@{user}</a>
                                    </div>
                                    <div class="cell">{s.sentSolutionsCount}</div>
                                    <div class="cell last-col">{s.correctSolutionsCount}</div>
                                </>
                            ))}
                        </div>
                    </div>
                ) : (
                    <>
                        <p>Nessuno ha ancora inviato soluzioni</p>
                    </>
                )}
            </main>
        </>
    )
}