import Excel from 'exceljs';

const arrayToSheet = (sheets, file_name) => {
    var workbook = new Excel.Workbook();
    sheets.forEach(({ sheet_name, data, merges, styles }, index) => {
        var sheet = workbook.addWorksheet(sheet_name || `sheet_${index}`);
        sheet.addRows(data);
        
 
if(merges) {
            merges.forEach(merge => {
                sheet.mergeCells(merge);
            })
        }
        if(styles) {
            var styleMap = [
                ['columns', 'column', 'getColumn'],
                ['rows', 'row', 'getRow'],
                ['cells', 'cell', 'getCell']
            ];
            styleMap.map(([k, i, a]) 
 
=> {
                if(styles[k]) {
                    styles[k].forEach(s => {
                        Object.keys(s.style).map(key => {
                            if(Array.isArray(s[i])) {
                                if(i === 'cell') {
                                    s[i].forEach(c 
 
=> {
                                        sheet[a](c)[key] = s.style[key];
                                    })
                                }
                                else {
                                    let [_s, _e] = s[i];
                                    for(let _i = _s; _i <= _e; _i ++) {
                                        sheet[a](_i)[key] = s.style[key];
                                    }
                                }
                            }
                            else {
                                sheet[a](s[i])[key] = s.style[key];
                            }
                        })
                    })
                }
            })
        }
    })
    workbook.xlsx.writeBuffer({ base64: true })
    .then(buffer => {
        var blob = new Blob([buffer], { type: 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet' });
        var a = document.createElement('a');
        a.href = URL.createObjectURL(blob);
        a.download = `${file_name}.xlsx`;
        a.click();
        var dispose = () => URL.revokeObjectURL(blob);
        setTimeout(dispose, 100);
    })
};

export { arrayToSheet }