/*
 * Copyright (C) 2016  Alex Yatskov <alex@foosoft.net>
 * Author: Alex Yatskov <alex@foosoft.net>
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 */


class Translator {
    constructor() {
        this.dictionary  = new Dictionary();
        this.deinflector = new Deinflector();
        this.initialized = false;
    }

    loadData(paths, callback) {
        if (this.initialized) {
            callback();
            return;
        }

        const pendingLoads = [];
        for (const key of ['rules', 'edict', 'enamdict', 'kanjidic']) {
            pendingLoads.push(key);
            Translator.loadData(paths[key], (response) => {
                switch (key) {
                    case 'rules':
                        this.deinflector.setRules(JSON.parse(response));
                        break;
                    case 'kanjidic':
                        this.dictionary.addKanjiData(Translator.parseCsv(response));
                        break;
                    case 'edict':
                    case 'enamdict':
                        this.dictionary.addTermData(Translator.parseCsv(response));
                        break;
                }

                pendingLoads.splice(pendingLoads.indexOf(key), 1);
                if (pendingLoads.length === 0) {
                    this.initialized = true;
                    callback();
                }
            });
        }
    }

    findTerm(text) {
        const groups = {};
        for (let i = text.length; i > 0; --i) {
            const term = text.slice(0, i);

            const dfs = this.deinflector.deinflect(term, t => {
                const tags = [];
                for (const d of this.dictionary.findTerm(t)) {
                    tags.push(d.tags);
                }

                return tags;
            });

            if (dfs === null) {
                this.processTerm(groups, term);
            } else {
                for (const df of dfs) {
                    this.processTerm(groups, df.source, df.rules, df.root);
                }
            }
        }

        let results = [];
        for (const key in groups) {
            results.push(groups[key]);
        }

        results = results.sort((v1, v2) => {
            const sl1 = v1.source.length;
            const sl2 = v2.source.length;
            if (sl1 > sl2) {
                return -1;
            } else if (sl1 < sl2) {
                return 1;
            }

            const p1 = v1.tags.indexOf('P') >= 0;
            const p2 = v2.tags.indexOf('P') >= 0;
            if (p1 && !p2) {
                return -1;
            } else if (!p1 && p2) {
                return 1;
            }

            const rl1 = v1.rules.length;
            const rl2 = v2.rules.length;
            if (rl1 < rl2) {
                return -1;
            } else if (rl2 > rl1) {
                return 1;
            }

            return 0;
        });

        let length = 0;
        for (const result of results) {
            length = Math.max(length, result.source.length);
        }

        return {results: results, length: length};
    }

    findKanji(text) {
        let results = [];

        const processed = {};
        for (const c of text) {
            if (!processed.has(c)) {
                results = results.concat(this.dictionary.findKanji(c));
                processed[c] = true;
            }
        }

        return results;
    }

    processTerm(groups, source, rules=[], root='') {
        for (const entry of this.dictionary.findTerm(root || source)) {
            if (entry.id in groups) {
                continue;
            }

            groups[entry.id] = {
                expression: entry.expression,
                reading:    entry.reading,
                glossary:   entry.glossary,
                tags:       entry.tags,
                source:     source,
                rules:      rules
            };
        }
    }

    static loadData(url, callback) {
        const xhr = new XMLHttpRequest();
        xhr.addEventListener('load', () => callback(xhr.responseText));
        xhr.open('GET', chrome.extension.getURL(url), true);
        xhr.send();
    }

    static parseCsv(data) {
        const result = [];
        for (const row of data.split('\n')) {
            if (row.length > 0) {
                result.push(row.split('\t'));
            }
        }

        return result;
    }
}