From b3910d30da1a9822cb674e3f77876f09ae57c58c Mon Sep 17 00:00:00 2001
From: Pranav C <61551451+pranavxc@users.noreply.github.com>
Date: Wed, 4 Aug 2021 18:42:59 +0530
Subject: [PATCH] feat: formula autocomplete

Signed-off-by: Pranav C <61551451+pranavxc@users.noreply.github.com>
---
 .../components/editColumn/formulaOptions.vue  | 139 ++++++++++++++++--
 packages/nc-gui/helpers/index.js              |  35 +++++
 2 files changed, 158 insertions(+), 16 deletions(-)

diff --git a/packages/nc-gui/components/project/spreadsheet/components/editColumn/formulaOptions.vue b/packages/nc-gui/components/project/spreadsheet/components/editColumn/formulaOptions.vue
index 3eb5015e9e..a80570993b 100644
--- a/packages/nc-gui/components/project/spreadsheet/components/editColumn/formulaOptions.vue
+++ b/packages/nc-gui/components/project/spreadsheet/components/editColumn/formulaOptions.vue
@@ -1,22 +1,67 @@
 <template>
-  <div>
-    <!-- todo: autocomplete based on available functions and metadata -->
-    <v-text-field
-      v-model="formula.value"
-      dense
-      outlined
-      class="caption"
-      hide-details="auto"
-      label="Formula"
-      persistent-hint
-      hint="Available formulas are ADD, AVG, CONCAT, +, -, /"
-      :rules="[v => !!v || 'Required', v => parseAndValidateFormula(v)]"
-    />
+  <div class="formula-wrapper">
+    <v-menu
+      v-model="autocomplete"
+      bottom
+      offset-y
+      nudge-bottom="-25px"
+      allow-overflow
+    >
+      <template #activator>
+        <!-- todo: autocomplete based on available functions and metadata -->
+        <v-text-field
+          ref="input"
+          v-model="formula.value"
+          dense
+          outlined
+          class="caption"
+          hide-details="auto"
+          label="Formula"
+          persistent-hint
+          hint="Available formulas are ADD, AVG, CONCAT, +, -, /"
+          :rules="[v => !!v || 'Required', v => parseAndValidateFormula(v)]"
+          autocomplete="off"
+          @input="handleInputDeb"
+        />
+      </template>
+      <!--    <div class="nc-autocomplete">-->
+      <v-list v-if="suggestion" dense max-height="50vh">
+        <v-list-item
+          v-for="it in suggestion"
+          :key="it"
+          dense
+          @mousedown.prevent="appendText(it)"
+        >
+          <span class="caption">{{ it }}</span>
+        </v-list-item>
+      </v-list>
+
+      <!--      <div>-->
+      <!--        <h1>Auto-complete...</h1>-->
+      <!--        <div-->
+      <!--          ref="input"-->
+      <!--          contenteditable="true"-->
+
+      <!--          @input="handleInputDeb"-->
+      <!--        />-->
+      <!--        <div ref="time" />-->
+      <!--        <div ref="fakeDiv" class="div" />-->
+
+      <!--        &lt;!&ndash;    </div>&ndash;&gt;-->
+      <!--      </div>-->
+    </v-menu>
+
+    <pre class="caption">
+      {{ suggestion }}
+    </pre>
   </div>
 </template>
 
 <script>
 
+import NcAutocompleteTree from '@/help/NcAutocompleteTree'
+import { insertAtCursor } from '@/helpers'
+import debounce from 'debounce'
 import jsep from 'jsep'
 
 export default {
@@ -26,8 +71,26 @@ export default {
     formula: {},
     // formulas: ['AVERAGE()', 'COUNT()', 'COUNTA()', 'COUNTALL()', 'SUM()', 'MIN()', 'MAX()', 'AND()', 'OR()', 'TRUE()', 'FALSE()', 'NOT()', 'XOR()', 'ISERROR()', 'IF()', 'LEN()', 'MID()', 'LEFT()', 'RIGHT()', 'FIND()', 'CONCATENATE()', 'T()', 'VALUE()', 'ARRAYJOIN()', 'ARRAYUNIQUE()', 'ARRAYCOMPACT()', 'ARRAYFLATTEN()', 'ROUND()', 'ROUNDUP()', 'ROUNDDOWN()', 'INT()', 'EVEN()', 'ODD()', 'MOD()', 'LOG()', 'EXP()', 'POWER()', 'SQRT()', 'CEILING()', 'FLOOR()', 'ABS()', 'RECORD_ID()', 'CREATED_TIME()', 'ERROR()', 'BLANK()', 'YEAR()', 'MONTH()', 'DAY()', 'HOUR()', 'MINUTE()', 'SECOND()', 'TODAY()', 'NOW()', 'WORKDAY()', 'DATETIME_PARSE()', 'DATETIME_FORMAT()', 'SET_LOCALE()', 'SET_TIMEZONE()', 'DATESTR()', 'TIMESTR()', 'TONOW()', 'FROMNOW()', 'DATEADD()', 'WEEKDAY()', 'WEEKNUM()', 'DATETIME_DIFF()', 'WORKDAY_DIFF()', 'IS_BEFORE()', 'IS_SAME()', 'IS_AFTER()', 'REPLACE()', 'REPT()', 'LOWER()', 'UPPER()', 'TRIM()', 'SUBSTITUTE()', 'SEARCH()', 'SWITCH()', 'LAST_MODIFIED_TIME()', 'ENCODE_URL_COMPONENT()', 'REGEX_EXTRACT()', 'REGEX_MATCH()', 'REGEX_REPLACE()']
     availableFunctions: ['AVG', 'ADD', 'CONCAT'],
-    availableBinOps: ['+', '-', '*', '/']
+    availableBinOps: ['+', '-', '*', '/'],
+    autocomplete: true,
+    suggestion: null
   }),
+  computed: {
+    suggestionsList() {
+      return [
+        ...this.meta.columns.map(c => ({ text: c.cn, type: 'column', c })),
+        ...this.availableFunctions.map(fn => ({ text: fn, type: 'function' })),
+        ...this.availableBinOps.map(op => ({ text: op, type: 'op' }))
+      ]
+    },
+    acTree() {
+      const ref = new NcAutocompleteTree()
+      for (const sug of this.suggestionsList) {
+        ref.add(sug.text)
+      }
+      return ref
+    }
+  },
   created() {
     this.formula = this.value ? { ...this.value } : {}
   },
@@ -121,11 +184,55 @@ export default {
         this.validateAgainstMeta(pt.right, arr)
       }
       return arr
+    },
+    appendText(it) {
+      if (it.type === 'function') {
+        insertAtCursor(this.$refs.input.$el.querySelector('input'), it.text + '()', it.text.length + 1)
+      } else {
+        insertAtCursor(this.$refs.input.$el.querySelector('input'), it.text)
+      }
+    },
+    _handleInputDeb: debounce(async function(self) {
+      await self.handleInput()
+    }, 250),
+    handleInputDeb() {
+      this._handleInputDeb(this)
+    },
+    handleInput() {
+      this.autocomplete = true
+      // const $fakeDiv = this.$refs.fakeDiv
+      this.suggestion = null
+      const query = this.formula.value
+      if (query !== '') {
+        const parts = query.split(' ')
+
+        const wordToComplete = parts.pop()
+
+        if (wordToComplete !== '') {
+          // get best match using popularity
+          this.suggestion = this.acTree.complete(wordToComplete)
+        } else {
+          // $span.textContent = '' // clear ghost span
+        }
+      } else {
+        // $time.textContent = ''
+        // $span.textContent = '' // clear ghost span
+      }
     }
   }
 }
 </script>
 
-<style scoped>
-
+<style scoped lang="scss">
+//.formula-wrapper {
+//  overflow: visible;
+//  position: relative;
+//
+//  .nc-autocomplete {
+//    position: absolute;
+//    //top: 100%;
+//    top:0;
+//    left: 0
+//  }
+//}
 </style>
diff --git a/packages/nc-gui/helpers/index.js b/packages/nc-gui/helpers/index.js
index 6f452743a1..30a8928350 100644
--- a/packages/nc-gui/helpers/index.js
+++ b/packages/nc-gui/helpers/index.js
@@ -12,6 +12,41 @@ export const isValidURL = (str) => {
 }
 
 export const parseIfInteger = v => /^\d+$/.test(v) ? +v : v
+
+// ref : https://stackoverflow.com/a/11077016
+export function insertAtCursor(myField, myValue, len) {
+  // IE support
+  if (document.selection) {
+    myField.focus()
+    const sel = document.selection.createRange()
+    sel.text = myValue
+  }
+
+  // MOZILLA and others
+  else if (myField.selectionStart || myField.selectionStart == '0') {
+    const startPos = myField.selectionStart
+    const endPos = myField.selectionEnd
+    myField.value = myField.value.substring(0, startPos) +
+      myValue +
+      myField.value.substring(endPos, myField.value.length)
+
+    const pos = +startPos + (len ?? myValue.length)
+    // https://stackoverflow.com/a/4302688
+    if (myField.setSelectionRange) {
+      myField.focus()
+      myField.setSelectionRange(pos, pos)
+    } else if (myField.createTextRange) {
+      const range = myField.createTextRange()
+      range.collapse(true)
+      range.moveEnd('character', pos)
+      range.moveStart('character', pos)
+      range.select()
+    }
+  } else {
+    myField.value += myValue
+  }
+}
+
 /**
  * @copyright Copyright (c) 2021, Xgene Cloud Ltd
  *