bookbrainz/bookbrainz-site

/*
 * Copyright (C) 2020  Sean Burke
 *
 * This program 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 2 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
 */

import {
    ADD_AUTHOR_CREDIT_ROW,
    CLEAR_AUTHOR_CREDIT,
    REMOVE_AUTHOR_CREDIT_ROW,
    REMOVE_EMPTY_CREDIT_ROWS,
    RESET_AUTHOR_CREDIT,
    UPDATE_CREDIT_AUTHOR_VALUE,
    UPDATE_CREDIT_DISPLAY_VALUE,
    UPDATE_CREDIT_JOIN_PHRASE_VALUE
} from './actions';

import Immutable from 'immutable';


const EMPTY_CREDIT_ROW = Immutable.Map({
    author: null,
    automaticJoinPhrase: true,
    joinPhrase: '',
    name: ''
});

/* Shamelessly stolen from MusicBrainz server:
    https://github.com/metabrainz/musicbrainz-server/blob/ece12896ff67524279d7e00998da300162d93c0b/root/static/scripts/edit/components/ArtistCreditEditor.js#L28
*/
function addAuthorCreditRow(state, newItemKey) {
    // Add a new empty author credit row
    let returnedState = state.set(newItemKey, EMPTY_CREDIT_ROW);

    const autoJoinPhraseRegex = /^(| & |, )$/;
    const acNames = returnedState.toJS();
    const keys = Object.keys(acNames);
    const {size} = returnedState;
    // If there are already names in the author credit, add join phrases to them.
    // Depending on how many credits there are the join phrase will be an ampersand or a comma
    if (size > 0) {
        // New empty author credit, last item
        const name0Key = keys[size - 1];
        const name0 = acNames[name0Key];
        if (name0 && name0.automaticJoinPhrase !== false) {
            returnedState = returnedState.setIn([name0Key, 'joinPhrase'], '');
        }
    }
    if (size > 1) {
        // Second to last author credit
        const name1Key = keys[size - 2];
        const name1 = acNames[name1Key];
        if (name1 && name1.automaticJoinPhrase !== false &&
            autoJoinPhraseRegex.test(name1.joinPhrase)) {
            returnedState = returnedState.setIn([name1Key, 'joinPhrase'], ' & ');
        }
    }

    if (size > 2) {
        // Third to last author credit
        const name2Key = keys[size - 3];
        const name2 = acNames[name2Key];
        if (name2 && name2.automaticJoinPhrase !== false &&
            autoJoinPhraseRegex.test(name2.joinPhrase)) {
            returnedState = returnedState.setIn([name2Key, 'joinPhrase'], ', ');
        }
      }

    return returnedState;
}

function setNewAuthorAndDisplay(state, payload) {
    if (payload.rowId === -1) {
        const firstRowKey = state.keySeq().first();
        payload.rowId = firstRowKey;
    }
    let returnState = state.setIn([payload.rowId, 'author'], Immutable.fromJS(payload));

    if (!payload.id) {
        // If the user has emptied the author field, also empty the display
        // name.
        returnState = returnState.setIn([payload.rowId, 'name'], '');
    }
    else {
        // When the user sets a new author, copy
        // the author's name to the display name field.
        returnState = returnState.setIn([payload.rowId, 'name'], payload.text);
    }

    return returnState;
}

function deleteAuthorCreditRow(state, payload) {
    const firstRowKey = state.keySeq().first();
    if (firstRowKey === payload) {
        return state.set(payload, EMPTY_CREDIT_ROW);
    }
    let returnState = state.delete(payload);

    // If names remain in the author credit, empty the join phrase for the last
    // name.
    const lastKey = returnState.keySeq().last();
    if (lastKey) {
        returnState = returnState.setIn([lastKey, 'joinPhrase'], '');
    }

    return returnState;
}
function deleteEmptyRows(state) {
    const firstRowKey = state.keySeq().first();
    const returnState = state.filterNot((row, rowId) =>
        (rowId !== firstRowKey) && row.get('author') === null && row.get('joinPhrase') === '' && row.get('name') === '');

    return returnState;
}
const initialState = {
    n0: EMPTY_CREDIT_ROW
};
function reducer(
    state = Immutable.OrderedMap(initialState),
    action
) {
    const {type, payload} = action;
    switch (type) {
        case ADD_AUTHOR_CREDIT_ROW:
            return addAuthorCreditRow(state, payload);
        case UPDATE_CREDIT_AUTHOR_VALUE:
            return setNewAuthorAndDisplay(state, payload);
        case UPDATE_CREDIT_DISPLAY_VALUE:
            return state.setIn([payload.rowId, 'name'], payload.value);
        case UPDATE_CREDIT_JOIN_PHRASE_VALUE: {
            const returnState =    state.setIn([payload.rowId, 'joinPhrase'], payload.value);
            // The join phrase has been modified manually by the user,
            // from now on it shouldn't be automatically modified
            return returnState.setIn([payload.rowId, 'automaticJoinPhrase'], false);
        }
        case REMOVE_AUTHOR_CREDIT_ROW:
            return deleteAuthorCreditRow(state, payload);
        case REMOVE_EMPTY_CREDIT_ROWS:
            return deleteEmptyRows(state);
        case CLEAR_AUTHOR_CREDIT:
            return Immutable.OrderedMap({});
        case RESET_AUTHOR_CREDIT:
            return Immutable.OrderedMap(initialState);
        // no default
    }
    return state;
}

export default reducer;