import React, {useState} from 'react';

import './App.scss';
import {SaiEntryProps, JutEntryProps, ElesuEntryProps, TukEntryProps} from './dbtypes';
import {SaiEntry, JutEntry, ElesuEntry, TukEntry} from './Entries';

const backendUrl = 'https://kucinakobackend.ichigo.everydayimshuflin.com';

enum Conlang {
    Saimiar = 'saimiar',
    Elesu = 'elesu',
    Tukvaysi = 'tukvaysi',
    Juteyuji = 'juteyuji',
}

enum SearchDirection {
    ToConlang,
    ToEnglish
}

const renderConlang = (conlang: Conlang): string => {
    if (conlang === Conlang.Saimiar) {
        return 'Saimiar';
    }

    if (conlang === Conlang.Elesu) {
        return 'Elésu';
    }

    if (conlang === Conlang.Juteyuji) {
        return 'Juteyuji';
    }

    if (conlang === Conlang.Tukvaysi) {
        return 'Tukvaysi';
    }
};

function buildRequest(searchTerm: string, conlang: Conlang, direction: SearchDirection, jsonHandler: (json: Object) => void) {
    const specForConlang = {
        [Conlang.Saimiar]: 'sai',
        [Conlang.Juteyuji]: 'jut',
        [Conlang.Tukvaysi]: 'tuk',
        [Conlang.Elesu]: 'elesu',
    };

    const offset = 0;
    const limit = 20;

    const conlangDb = conlang.toString();
    const conlangSpec = specForConlang[conlang];
    const field = direction === SearchDirection.ToConlang ? 'eng' : conlangSpec;

    const params = new URLSearchParams([
        [field, `like.*${searchTerm}*`],
        ['order', conlangSpec],
        ['limit', limit],
        ['offset', offset],
    ]);

    const effectiveUri = `${backendUrl}/${conlangDb}?${params}`;

    fetch(`${effectiveUri}`)
        .then((resp) => resp.json())
        .then((json) => {
            jsonHandler(json);
        });
}

interface EntryProps {
    conlang: Conlang;
    entry: SaiEntryProps | JutEntryProps | ElesuEntryProps | TukEntryProps;
    key: string;
}

const Entry = (props: EntryProps) => {
    const {conlang} = props;
    if (conlang === Conlang.Saimiar) {
        return <SaiEntry entry={ props.entry as SaiEntryProps } />;
    }

    if (conlang === Conlang.Juteyuji) {
        return <JutEntry entry={ props.entry as JutEntryProps } />;
    }

    if (conlang === Conlang.Elesu) {
        return <ElesuEntry entry={ props.entry as ElesuEntryProps } />;
    }

    if (conlang === Conlang.Tukvaysi) {
        return <TukEntry entry={ props.entry as TukEntryProps } />;
    }
};

interface ResultsProps {
    searchResults: Array<any>;
    searchTerm: string;
    conlang: Conlang;
    direction: SearchDirection;
}

const Results = (props: ResultsProps) => {
    const content = () => {
        const {conlang} = props;
        const num = props.searchResults.length;

        const renderedName = renderConlang(conlang);
        const searchType = (props.direction === SearchDirection.ToConlang) ? `English -> ${renderedName}` : `${renderedName} -> English`;
        const result = num === 1 ? 'result' : 'results';
        const header = (
            <div className="searchResultHeader" key="header">
        Searched for <b>{ props.searchTerm }</b>, { searchType }, found { num } { result }
            </div>);
        const entries = props.searchResults.map(
            (entry, _idx) => <Entry entry={ entry } key= { entry.id } conlang={ conlang } />,
        );
        return [header].concat(entries);
    };

    const results = props.searchResults;
    return (
        <div className="results">
            { results ? content() : 'No search' }
        </div>
    );
};

const App = (_props) => {
    const defaultConlang = window.sessionStorage.getItem('conlang') as Conlang || Conlang.Saimiar;
    const [searchResults, setSearchResults] = useState(null);
    const [conlang, setConlangState] = useState(defaultConlang);
    const [direction, setDirection] = useState(null);
    const [searchTerm, setSearchTerm] = useState(null);

    const [searchBoxInput, setSearchBoxInput] = useState('');

    const setConlang = (conlang: Conlang) => {
        setConlangState(conlang);
        window.sessionStorage.setItem('conlang', conlang);
    };

    const searchConlang = (_evt) => {
        const searchTerm = searchBoxInput;
        if (searchTerm === '') {
            setSearchResults(null);
            setSearchTerm(null);
            setDirection(null);
            return;
        }

        buildRequest(searchTerm, conlang, SearchDirection.ToEnglish, (json) => {
            setSearchResults(json);
            setSearchTerm(searchTerm);
            setDirection(SearchDirection.ToEnglish);
        });
    };

    const searchEng = (_evt) => {
        const searchTerm = searchBoxInput;
        if (searchTerm === '') {
            setSearchResults(null);
            setSearchTerm(null);
            setDirection(null);
        } else {
            buildRequest(searchTerm, conlang, SearchDirection.ToConlang, (json) => {
                setSearchResults(json);
                setSearchTerm(searchTerm);
                setDirection(SearchDirection.ToConlang);
            });
        }
    };

    const handleLangChange = (evt) => {
        const conlang: Conlang = evt.target.value as Conlang;
        setConlang(conlang);
        setSearchResults(null);
    };

    const conlangs = [Conlang.Saimiar, Conlang.Elesu, Conlang.Tukvaysi, Conlang.Juteyuji];
    const langSelectDropdown = (
        <select value={conlang} onChange={ handleLangChange }>
            {conlangs.map((conlang) => <option value={conlang} key={conlang}>{renderConlang(conlang)}</option>)}
        </select>
    );

    return (
        <main>
            <div className="container">
                <div className="search">
                    <h1>Kucinako - Wordbook of Arzhanai languages</h1>
                    <p><b>Kucinako</b> is a dictionary of words in various languages of the world Arzhanø, and their English
                    equivalents.</p>
                    <div className="textInput">
                        <input className="textInput" type="text" value={ searchBoxInput } onChange={ (evt) => {
                            setSearchBoxInput(evt.target.value);
                        } } />
                    </div>
                    <br/>
                    { langSelectDropdown }
                    <button onClick={ searchConlang } className="searchButton">{renderConlang(conlang)}</button>
                    <button onClick={ searchEng } className="searchButton">English</button>
                </div>
                <Results
                    searchResults={ searchResults }
                    searchTerm= { searchTerm }
                    conlang={ conlang }
                    direction={ direction }
                />
            </div>
        </main>
    );
};

export default App;