3 files changed, 141 insertions, 4 deletions
diff --git a/src_js/opcut/fs.js b/src_js/opcut/fs.js
new file mode 100644
index 0000000..b1d464e
--- /dev/null
+++ b/src_js/opcut/fs.js
@@ -0,0 +1,71 @@
+import h from 'hyperscript';
+import FileSaver from 'file-saver';
+
+import * as ev from 'opcut/ev';
+
+
+export function loadText(ext) {
+    const el = h('input', {
+        style: 'display: none',
+        type: 'file',
+        accept: ext});
+    const promise = new Promise(resolve => {
+        ev.on(el, 'change', evt => {
+            const file = u.get(['files', 0], evt.target);
+            if (!file)
+                return;
+            const fileReader = new FileReader();
+            fileReader.onload = () => {
+                const data = fileReader.result;
+                resolve(data);
+            };
+            fileReader.readAsText(file);
+        });
+        el.click();
+    });
+    return promise;
+}
+
+
+export function saveText(text, fileName) {
+    const blob = stringToBlob(text);
+    FileSaver.saveAs(blob, fileName);
+}
+
+
+export function saveB64Data(b64Data, fileName) {
+    const blob = b64ToBlob(b64Data);
+    FileSaver.saveAs(blob, fileName);
+}
+
+
+function stringToBlob(strData, contentType) {
+    contentType = contentType || '';
+    return new Blob([strData], {type: contentType});
+}
+
+
+// http://stackoverflow.com/a/16245768
+function b64ToBlob(b64Data, contentType, sliceSize) {
+    contentType = contentType || '';
+    sliceSize = sliceSize || 512;
+
+    var byteCharacters = atob(b64Data);
+    var byteArrays = [];
+
+    for (var offset = 0; offset < byteCharacters.length; offset += sliceSize) {
+        var slice = byteCharacters.slice(offset, offset + sliceSize);
+
+        var byteNumbers = new Array(slice.length);
+        for (var i = 0; i < slice.length; i++) {
+            byteNumbers[i] = slice.charCodeAt(i);
+        }
+
+        var byteArray = new Uint8Array(byteNumbers);
+
+        byteArrays.push(byteArray);
+    }
+
+    var blob = new Blob(byteArrays, {type: contentType});
+    return blob;
+}
diff --git a/src_js/opcut/grid.js b/src_js/opcut/grid.js
index b72e0b0..972341d 100644
--- a/src_js/opcut/grid.js
+++ b/src_js/opcut/grid.js
@@ -1,3 +1,5 @@
+import Papa from 'papaparse';
+
 import r from 'opcut/renderer';
 import * as u from 'opcut/util';
 import * as ev from 'opcut/ev';
@@ -68,7 +70,7 @@ export function tbody(gridPath, columns, validators) {
 }
 
 
-export function tfoot(gridPath, colspan, newItem) {
+export function tfoot(gridPath, colspan, newItem, csvColumns) {
     const itemsPath = [gridPath, 'items'];
     return ['tfoot',
         ['tr',
@@ -85,7 +87,27 @@ export function tfoot(gridPath, colspan, newItem) {
                         'ev-click': () => r.set(itemsPath, [])},
                         ['span.fa.fa-trash-o'],
                         ' Remove all'
-                    ]
+                    ],
+                    (!csvColumns ?
+                        [] :
+                        [
+                            ['button', {
+                                'ev-click': () => {
+                                    const items = importCsv(csvColumns, newItem);
+                                    if (!items)
+                                        return;
+                                    r.change(itemsPath, state => state.concat(items));
+                                }},
+                                ['span.fa.fa-download'],
+                                ' Import from CSV'
+                            ],
+                            ['button', {
+                                'ev-click': () => exportCsv(r.get(itemsPath), csvColumns)},
+                                ['span.fa.fa-upload'],
+                                ' Export to CSV'
+                            ]
+                        ]
+                    )
                 ]
             ]
         ]
@@ -93,6 +115,17 @@ export function tfoot(gridPath, colspan, newItem) {
 }
 
 
+export function createStringCsvColumns(...columns) {
+    return u.pipe(
+        u.map(i => [i, {
+            toString: u.get(i),
+            toItem: u.set(i)
+        }]),
+        u.fromPairs
+    )(columns);
+}
+
+
 export function deleteColumn(gridPath, showUpDown, onDeleteCb) {
     const itemsPath = [gridPath, 'items'];
     return (i, index) => [
@@ -173,3 +206,36 @@ export function selectColumn(gridPath, column, values) {
         ];
     };
 }
+
+
+function importCsv(csvColumns, newItem) {
+    fs.loadText('csv').then(csvData => {
+        const result = Papa.parse(csvData, {
+            delimiter: ';',
+            skipEmptyLines: true,
+            header: true
+        });
+
+        const items = [];
+        for (let i of result.data) {
+            if (!Object.keys(i).every(k => u.contains(k, Object.keys(csvColumns))))
+                continue;
+            const item = u.reduce(
+                (acc, [name, column]) => column.toItem(i[name], acc),
+                newItem,
+                u.toPairs(csvColumns));
+            items.push(item);
+        }
+        return items;
+    });
+}
+
+
+function exportCsv(items, csvColumns) {
+    const csvData = Papa.unparse(
+        items.map(item => u.map(column => column.toString(item))(csvColumns)), {
+            delimiter: ';',
+            skipEmptyLines: true,
+            header: true});
+    fs.saveText(csvData, 'data.csv');
+}
diff --git a/src_js/opcut/vt.js b/src_js/opcut/vt.js
index 39f6188..c13d35a 100644
--- a/src_js/opcut/vt.js
+++ b/src_js/opcut/vt.js
@@ -23,7 +23,7 @@ function leftPanel() {
                 ['span.fa.fa-github']
             ]
         ],
-        ['div',
+        ['div.group',
             ['label', 'Method'],
             ['select',
                 ['FORWARD_GREEDY', 'GREEDY'].map(method =>
@@ -36,7 +36,7 @@ function leftPanel() {
                     ])
             ]
         ],
-        ['div',
+        ['div.group',
             ['label', 'Cut width'],
             ['input', {
                 props: {