import {Feature} from './feature';
import Dom from '../dom';
import Arr from '../array';
import Str from '../string';
import Sort from '../sort';
import Event from '../event';
import Types from '../types';
import {CHECKLIST, NONE} from '../const';

const SORT_ERROR = 'Filter options for column {0} cannot be sorted in ' +
    '{1} manner.';

export class CheckList extends Feature {

    /**
     * Checklist UI component
     * @param {Object} tf TableFilter instance
     */
    constructor(tf) {
        super(tf, 'checkList');

        // Configuration object
        let f = tf.config();

        this.checkListDiv = []; //checklist container div
        //defines css class for div containing checklist filter
        this.checkListDivCssClass = f.div_checklist_css_class ||
            'div_checklist';
        //defines css class for checklist filters
        this.checkListCssClass = f.checklist_css_class || 'flt_checklist';
        //defines css class for checklist item (li)
        this.checkListItemCssClass = f.checklist_item_css_class ||
            'flt_checklist_item';
        //defines css class for selected checklist item (li)
        this.checkListSlcItemCssClass = f.checklist_selected_item_css_class ||
            'flt_checklist_slc_item';
        //Load on demand text
        this.activateCheckListTxt = f.activate_checklist_text ||
            'Click to load filter data';
        //defines css class for checklist filters
        this.checkListItemDisabledCssClass =
            f.checklist_item_disabled_css_class ||
            'flt_checklist_item_disabled';
        this.enableCheckListResetFilter =
            f.enable_checklist_reset_filter === false ? false : true;
        //checklist filter container div
        this.prfxCheckListDiv = 'chkdiv_';

        this.isCustom = null;
        this.opts = null;
        this.optsTxt = null;
        this.excludedOpts = null;
    }

    onChange(evt) {
        let elm = Event.target(evt);
        let tf = this.tf;
        this.emitter.emit('filter-focus', tf, elm);
        tf.filter();
    }

    optionClick(evt) {
        this.setCheckListValues(evt.target);
        this.onChange(evt);
    }

    onCheckListClick(evt) {
        let elm = Event.target(evt);
        if (this.tf.loadFltOnDemand && elm.getAttribute('filled') === '0') {
            let ct = elm.getAttribute('ct');
            let div = this.checkListDiv[ct];
            this.build(ct);
            Event.remove(div, 'click', (evt) => this.onCheckListClick(evt));
        }
    }

    /**
     * Initialize checklist filter
     * @param  {Number}     colIndex   Column index
     * @param  {Boolean}    isExternal External filter flag
     * @param  {DOMElement} container  Dom element containing the filter
     */
    init(colIndex, isExternal, container) {
        let tf = this.tf;
        let externalFltTgtId = isExternal ?
            tf.externalFltTgtIds[colIndex] : null;

        let divCont = Dom.create('div',
            ['id', this.prfxCheckListDiv + colIndex + '_' + tf.id],
            ['ct', colIndex], ['filled', '0']);
        divCont.className = this.checkListDivCssClass;

        //filter is appended in desired element
        if (externalFltTgtId) {
            Dom.id(externalFltTgtId).appendChild(divCont);
            tf.externalFltEls.push(divCont);
        } else {
            container.appendChild(divCont);
        }

        this.checkListDiv[colIndex] = divCont;
        tf.fltIds.push(tf.prfxFlt + colIndex + '_' + tf.id);

        if (!tf.loadFltOnDemand) {
            this.build(colIndex);
        } else {
            Event.add(divCont, 'click', (evt) => this.onCheckListClick(evt));
            divCont.appendChild(Dom.text(this.activateCheckListTxt));
        }

        this.emitter.on(
            ['build-checklist-filter'],
            (tf, colIndex, isExternal) => this.build(colIndex, isExternal)
        );

        this.emitter.on(
            ['select-checklist-options'],
            (tf, colIndex, values) => this.selectOptions(colIndex, values)
        );

        this.initialized = true;
    }

    /**
     * Build checklist UI
     * @param  {Number}  colIndex   Column index
     */
    build(colIndex) {
        let tf = this.tf;
        colIndex = parseInt(colIndex, 10);

        this.emitter.emit('before-populating-filter', tf, colIndex);

        this.opts = [];
        this.optsTxt = [];

        let flt = this.checkListDiv[colIndex];
        let ul = Dom.create(
            'ul', ['id', tf.fltIds[colIndex]], ['colIndex', colIndex]);
        ul.className = this.checkListCssClass;
        Event.add(ul, 'change', (evt) => this.onChange(evt));

        let rows = tf.tbl.rows;
        this.isCustom = tf.isCustomOptions(colIndex);

        let activeIdx;
        let activeFilterId = tf.getActiveFilterId();
        if (tf.linkedFilters && activeFilterId) {
            activeIdx = tf.getColumnIndexFromFilterId(activeFilterId);
        }

        let filteredDataCol = [];
        if (tf.linkedFilters && tf.disableExcludedOptions) {
            this.excludedOpts = [];
        }

        flt.innerHTML = '';

        for (let k = tf.refRow; k < tf.nbRows; k++) {
            // always visible rows don't need to appear on selects as always
            // valid
            if (tf.hasVisibleRows && tf.visibleRows.indexOf(k) !== -1) {
                continue;
            }

            let cells = rows[k].cells;
            let ncells = cells.length;

            // checks if row has exact cell #
            if (ncells !== tf.nbCells || this.isCustom) {
                continue;
            }

            // this loop retrieves cell data
            for (let j = 0; j < ncells; j++) {
                // WTF: cyclomatic complexity hell :)
                if ((colIndex === j && (!tf.linkedFilters ||
                    (tf.linkedFilters && tf.disableExcludedOptions))) ||
                    (colIndex === j && tf.linkedFilters &&
                        ((rows[k].style.display === '' && !tf.paging) ||
                            (tf.paging && ((!activeIdx ||
                                activeIdx === colIndex) ||
                                (activeIdx != colIndex &&
                                    tf.validRowsIndex.indexOf(k) != -1)))))) {

                    let cellData = tf.getCellData(cells[j]);
                    //Vary Peter's patch
                    let cellString = Str.matchCase(cellData, tf.matchCase);
                    // checks if celldata is already in array
                    if (!Arr.has(this.opts, cellString, tf.matchCase)) {
                        this.opts.push(cellData);
                    }
                    let filteredCol = filteredDataCol[j];
                    if (tf.linkedFilters && tf.disableExcludedOptions) {
                        if (!filteredCol) {
                            filteredCol = tf.getFilteredDataCol(j);
                        }
                        if (!Arr.has(filteredCol, cellString, tf.matchCase) &&
                            !Arr.has(this.excludedOpts,
                                cellString, tf.matchCase)) {
                            this.excludedOpts.push(cellData);
                        }
                    }
                }
            }
        }

        //Retrieves custom values
        if (this.isCustom) {
            let customValues = tf.getCustomOptions(colIndex);
            this.opts = customValues[0];
            this.optsTxt = customValues[1];
        }

        if (tf.sortSlc && !this.isCustom) {
            if (!tf.matchCase) {
                this.opts.sort(Sort.ignoreCase);
                if (this.excludedOpts) {
                    this.excludedOpts.sort(Sort.ignoreCase);
                }
            } else {
                this.opts.sort();
                if (this.excludedOpts) {
                    this.excludedOpts.sort();
                }
            }
        }
        //asc sort
        if (tf.sortNumAsc.indexOf(colIndex) != -1) {
            try {
                this.opts.sort(Sort.numSortAsc);
                if (this.excludedOpts) {
                    this.excludedOpts.sort(Sort.numSortAsc);
                }
                if (this.isCustom) {
                    this.optsTxt.sort(Sort.numSortAsc);
                }
            } catch (e) {
                throw new Error(SORT_ERROR.replace('{0}', colIndex)
                    .replace('{1}', 'ascending'));
            }//in case there are alphanumeric values
        }
        //desc sort
        if (tf.sortNumDesc.indexOf(colIndex) != -1) {
            try {
                this.opts.sort(Sort.numSortDesc);
                if (this.excludedOpts) {
                    this.excludedOpts.sort(Sort.numSortDesc);
                }
                if (this.isCustom) {
                    this.optsTxt.sort(Sort.numSortDesc);
                }
            } catch (e) {
                throw new Error(SORT_ERROR.replace('{0}', colIndex)
                    .replace('{1}', 'descending'));
            }//in case there are alphanumeric values
        }

        this.addChecks(colIndex, ul);

        if (tf.loadFltOnDemand) {
            flt.innerHTML = '';
        }
        flt.appendChild(ul);
        flt.setAttribute('filled', '1');

        this.emitter.emit('after-populating-filter', tf, colIndex, flt);
    }

    /**
     * Add checklist options
     * @param {Number} colIndex  Column index
     * @param {Object} ul        Ul element
     */
    addChecks(colIndex, ul) {
        let tf = this.tf;
        let chkCt = this.addTChecks(colIndex, ul);

        for (let y = 0; y < this.opts.length; y++) {
            let val = this.opts[y]; //item value
            let lbl = this.isCustom ? this.optsTxt[y] : val; //item text
            let li = Dom.createCheckItem(
                tf.fltIds[colIndex] + '_' + (y + chkCt), val, lbl);
            li.className = this.checkListItemCssClass;
            if (tf.linkedFilters && tf.disableExcludedOptions &&
                Arr.has(this.excludedOpts,
                    Str.matchCase(val, tf.matchCase), tf.matchCase)) {
                Dom.addClass(li, this.checkListItemDisabledCssClass);
                li.check.disabled = true;
                li.disabled = true;
            } else {
                Event.add(li.check, 'click', (evt) => this.optionClick(evt));
            }
            ul.appendChild(li);

            if (val === '') {
                //item is hidden
                li.style.display = NONE;
            }
        }
    }

    /**
     * Add checklist header option
     * @param {Number} colIndex Column index
     * @param {Object} ul       Ul element
     */
    addTChecks(colIndex, ul) {
        let tf = this.tf;
        let chkCt = 1;
        let li0 = Dom.createCheckItem(
            tf.fltIds[colIndex] + '_0', '', tf.displayAllText);
        li0.className = this.checkListItemCssClass;
        ul.appendChild(li0);

        Event.add(li0.check, 'click', (evt) => this.optionClick(evt));

        if (!this.enableCheckListResetFilter) {
            li0.style.display = NONE;
        }

        if (tf.enableEmptyOption) {
            let li1 = Dom.createCheckItem(
                tf.fltIds[colIndex] + '_1', tf.emOperator, tf.emptyText);
            li1.className = this.checkListItemCssClass;
            ul.appendChild(li1);
            Event.add(li1.check, 'click', (evt) => this.optionClick(evt));
            chkCt++;
        }

        if (tf.enableNonEmptyOption) {
            let li2 = Dom.createCheckItem(
                tf.fltIds[colIndex] + '_2',
                tf.nmOperator,
                tf.nonEmptyText
            );
            li2.className = this.checkListItemCssClass;
            ul.appendChild(li2);
            Event.add(li2.check, 'click', (evt) => this.optionClick(evt));
            chkCt++;
        }
        return chkCt;
    }

    /**
     * Store checked options in DOM element attribute
     * @param {Object} o checklist option DOM element
     */
    setCheckListValues(o) {
        if (!o) {
            return;
        }

        let tf = this.tf;
        let chkValue = o.value; //checked item value
        // TODO: provide helper to extract column index, ugly!
        let chkIndex = parseInt(o.id.split('_')[2], 10);
        let colIdx = tf.getColumnIndexFromFilterId(o.id);
        let itemTag = 'LI';

        let n = tf.getFilterElement(parseInt(colIdx, 10));
        let li = n.childNodes[chkIndex];
        let colIndex = n.getAttribute('colIndex');
        let fltValue = n.getAttribute('value'); //filter value (ul tag)
        let fltIndexes = n.getAttribute('indexes'); //selected items (ul tag)

        if (o.checked) {
            //show all item
            if (chkValue === '') {
                if ((fltIndexes && fltIndexes !== '')) {
                    //items indexes
                    let indSplit = fltIndexes.split(tf.separator);
                    //checked items loop
                    for (let u = 0; u < indSplit.length; u++) {
                        //checked item
                        let cChk = Dom.id(tf.fltIds[colIndex] + '_' +
                            indSplit[u]);
                        if (cChk) {
                            cChk.checked = false;
                            Dom.removeClass(
                                n.childNodes[indSplit[u]],
                                this.checkListSlcItemCssClass
                            );
                        }
                    }
                }
                n.setAttribute('value', '');
                n.setAttribute('indexes', '');

            } else {
                fltValue = (fltValue) ? fltValue : '';
                chkValue = Str.trim(fltValue + ' ' + chkValue + ' ' +
                    tf.orOperator);
                chkIndex = fltIndexes + chkIndex + tf.separator;
                n.setAttribute('value', chkValue);
                n.setAttribute('indexes', chkIndex);
                //1st option unchecked
                if (Dom.id(tf.fltIds[colIndex] + '_0')) {
                    Dom.id(tf.fltIds[colIndex] + '_0').checked = false;
                }
            }

            if (li.nodeName === itemTag) {
                Dom.removeClass(
                    n.childNodes[0], this.checkListSlcItemCssClass);
                Dom.addClass(li, this.checkListSlcItemCssClass);
            }
        } else { //removes values and indexes
            if (chkValue !== '') {
                let replaceValue = new RegExp(
                    Str.rgxEsc(chkValue + ' ' + tf.orOperator));
                fltValue = fltValue.replace(replaceValue, '');
                n.setAttribute('value', Str.trim(fltValue));

                let replaceIndex = new RegExp(
                    Str.rgxEsc(chkIndex + tf.separator));
                fltIndexes = fltIndexes.replace(replaceIndex, '');
                n.setAttribute('indexes', fltIndexes);
            }
            if (li.nodeName === itemTag) {
                Dom.removeClass(li, this.checkListSlcItemCssClass);
            }
        }
    }

    /**
     * Select filter options programmatically
     * @param  {Number} colIndex Column index
     * @param  {Array}  values   Array of option values to select
     */
    selectOptions(colIndex, values = []) {
        let tf = this.tf;
        let flt = tf.getFilterElement(colIndex);
        if (tf.getFilterType(colIndex) !== CHECKLIST || !flt) {
            return;
        }

        let lisNb = Dom.tag(flt, 'li').length;

        flt.setAttribute('value', '');
        flt.setAttribute('indexes', '');

        for (let k = 0; k < lisNb; k++) {
            let li = Dom.tag(flt, 'li')[k],
                lbl = Dom.tag(li, 'label')[0],
                chk = Dom.tag(li, 'input')[0],
                lblTxt = Str.matchCase(Dom.getText(lbl), tf.caseSensitive);
            if (lblTxt !== '' && Arr.has(values, lblTxt, tf.caseSensitive)) {
                chk.checked = true;
                this.setCheckListValues(chk);
            }
            else {
                chk.checked = false;
                this.setCheckListValues(chk);
            }
        }
    }

    /**
     * Get filter values for a given column index
     * @param {Number} colIndex Column index
     * @returns {Array} values Collection of selected values
     */
    getValues(colIndex) {
        let tf = this.tf;
        let flt = tf.getFilterElement(colIndex);
        let fltAttr = flt.getAttribute('value');
        let values = Types.isEmpty(fltAttr) ? '' : fltAttr;

        //removes last operator ||
        values = values.substr(0, values.length - 3);
        //turn || separated values into array
        values = values.split(' ' + tf.orOperator + ' ');

        return values;
    }

    destroy() {
        this.emitter.off(
            ['build-checklist-filter'],
            (tf, colIndex, isExternal) => this.build(colIndex, isExternal)
        );
        this.emitter.off(
            ['select-checklist-options'],
            (tf, colIndex, values) => this.selectOptions(colIndex, values)
        );
    }
}