Add togglable advanced gas controls on send and confirm screens (#6112)

* Extract advanced gas input controls to their own component

* Add advanced inline gas toggle to settings

* Add optional advanced inline gas to send send screen

* Adds optional advanced gas inputs to the confirm screen

* Add info modals for advanced gas inputs.

* Fix translation of advance gas toggle description.

* Lint and unit test fixes for inline-advanced-gas-inputs

* Increase margin above advanced options button on send screen

* Move methods from constructor to property syntax in advanced-gas-inputs.component

19 files changed, 597 insertions, 36 deletions

diff --git a/ui/app/components/confirm-page-container/confirm-detail-row/index.scss b/ui/app/components/confirm-page-container/confirm-detail-row/index.scss
index 580a41fde..1672ef8c6 100644
--- a/ui/app/components/confirm-page-container/confirm-detail-row/index.scss
+++ b/ui/app/components/confirm-page-container/confirm-detail-row/index.scss
@@ -43,4 +43,8 @@
       font-size: .625rem;
     }
   }
+
+  .advanced-gas-inputs__gas-edit-rows {
+    margin-bottom: 16px;
+  }
 }
diff --git a/ui/app/components/confirm-page-container/confirm-page-container-content/index.scss b/ui/app/components/confirm-page-container/confirm-page-container-content/index.scss
index 698e624f4..78639a435 100644
--- a/ui/app/components/confirm-page-container/confirm-page-container-content/index.scss
+++ b/ui/app/components/confirm-page-container/confirm-page-container-content/index.scss
@@ -52,6 +52,10 @@
 
   &__gas-fee {
     border-bottom: 1px solid $geyser;
+
+    .advanced-gas-inputs__gas-edit-rows {
+      margin-bottom: 16px;
+    }
   }
 
   &__function-type {
diff --git a/ui/app/components/gas-customization/advanced-gas-inputs/advanced-gas-inputs.component.js b/ui/app/components/gas-customization/advanced-gas-inputs/advanced-gas-inputs.component.js
new file mode 100644
index 000000000..f0abff478
--- /dev/null
+++ b/ui/app/components/gas-customization/advanced-gas-inputs/advanced-gas-inputs.component.js
@@ -0,0 +1,146 @@
+import React, { Component } from 'react'
+import PropTypes from 'prop-types'
+import classnames from 'classnames'
+import debounce from 'lodash.debounce'
+
+export default class AdvancedTabContent extends Component {
+  static contextTypes = {
+    t: PropTypes.func,
+  }
+
+  static propTypes = {
+    updateCustomGasPrice: PropTypes.func,
+    updateCustomGasLimit: PropTypes.func,
+    customGasPrice: PropTypes.number,
+    customGasLimit: PropTypes.number,
+    insufficientBalance: PropTypes.bool,
+    customPriceIsSafe: PropTypes.bool,
+    isSpeedUp: PropTypes.bool,
+    showGasPriceInfoModal: PropTypes.func,
+    showGasLimitInfoModal: PropTypes.func,
+  }
+
+  debouncedGasLimitReset = debounce((dVal) => {
+    if (dVal < 21000) {
+      this.props.updateCustomGasLimit(21000)
+    }
+  }, 1000, { trailing: true })
+
+  onChangeGasLimit = (val) => {
+    this.props.updateCustomGasLimit(val)
+    this.debouncedGasLimitReset(val)
+  }
+
+  gasInputError ({ labelKey, insufficientBalance, customPriceIsSafe, isSpeedUp, value }) {
+    const { t } = this.context
+    let errorText
+    let errorType
+    let isInError = true
+
+
+    if (insufficientBalance) {
+      errorText = t('insufficientBalance')
+      errorType = 'error'
+    } else if (labelKey === 'gasPrice' && isSpeedUp && value === 0) {
+      errorText = t('zeroGasPriceOnSpeedUpError')
+      errorType = 'error'
+    } else if (labelKey === 'gasPrice' && !customPriceIsSafe) {
+      errorText = t('gasPriceExtremelyLow')
+      errorType = 'warning'
+    } else {
+      isInError = false
+    }
+
+    return {
+      isInError,
+      errorText,
+      errorType,
+    }
+  }
+
+  gasInput ({ labelKey, value, onChange, insufficientBalance, showGWEI, customPriceIsSafe, isSpeedUp }) {
+    const {
+      isInError,
+      errorText,
+      errorType,
+    } = this.gasInputError({ labelKey, insufficientBalance, customPriceIsSafe, isSpeedUp, value })
+
+    return (
+      <div className="advanced-gas-inputs__gas-edit-row__input-wrapper">
+        <input
+          className={classnames('advanced-gas-inputs__gas-edit-row__input', {
+            'advanced-gas-inputs__gas-edit-row__input--error': isInError && errorType === 'error',
+            'advanced-gas-inputs__gas-edit-row__input--warning': isInError && errorType === 'warning',
+          })}
+          type="number"
+          value={value}
+          onChange={event => onChange(Number(event.target.value))}
+        />
+        <div className={classnames('advanced-gas-inputs__gas-edit-row__input-arrows', {
+          'advanced-gas-inputs__gas-edit-row__input--error': isInError && errorType === 'error',
+          'advanced-gas-inputs__gas-edit-row__input--warning': isInError && errorType === 'warning',
+        })}>
+          <div className="advanced-gas-inputs__gas-edit-row__input-arrows__i-wrap" onClick={() => onChange(value + 1)}><i className="fa fa-sm fa-angle-up" /></div>
+          <div className="advanced-gas-inputs__gas-edit-row__input-arrows__i-wrap" onClick={() => onChange(value - 1)}><i className="fa fa-sm fa-angle-down" /></div>
+        </div>
+        { isInError
+          ? <div className={`advanced-gas-inputs__gas-edit-row__${errorType}-text`}>
+              { errorText }
+            </div>
+          : null }
+      </div>
+    )
+  }
+
+  infoButton (onClick) {
+    return <i className="fa fa-info-circle" onClick={onClick} />
+  }
+
+  renderGasEditRow (gasInputArgs) {
+    return (
+      <div className="advanced-gas-inputs__gas-edit-row">
+        <div className="advanced-gas-inputs__gas-edit-row__label">
+          { this.context.t(gasInputArgs.labelKey) }
+          { this.infoButton(() => gasInputArgs.infoOnClick()) }
+        </div>
+        { this.gasInput(gasInputArgs) }
+      </div>
+    )
+  }
+
+  render () {
+    const {
+      customGasPrice,
+      updateCustomGasPrice,
+      customGasLimit,
+      insufficientBalance,
+      customPriceIsSafe,
+      isSpeedUp,
+      showGasPriceInfoModal,
+      showGasLimitInfoModal,
+    } = this.props
+
+    return (
+      <div className="advanced-gas-inputs__gas-edit-rows">
+        { this.renderGasEditRow({
+          labelKey: 'gasPrice',
+          value: customGasPrice,
+          onChange: updateCustomGasPrice,
+          insufficientBalance,
+          customPriceIsSafe,
+          showGWEI: true,
+          isSpeedUp,
+          infoOnClick: showGasPriceInfoModal,
+        }) }
+        { this.renderGasEditRow({
+          labelKey: 'gasLimit',
+          value: customGasLimit,
+          onChange: this.onChangeGasLimit,
+          insufficientBalance,
+          customPriceIsSafe,
+          infoOnClick: showGasLimitInfoModal,
+        }) }
+      </div>
+    )
+  }
+}
diff --git a/ui/app/components/gas-customization/advanced-gas-inputs/advanced-gas-inputs.container.js b/ui/app/components/gas-customization/advanced-gas-inputs/advanced-gas-inputs.container.js
new file mode 100644
index 000000000..883d11c6d
--- /dev/null
+++ b/ui/app/components/gas-customization/advanced-gas-inputs/advanced-gas-inputs.container.js
@@ -0,0 +1,12 @@
+import { connect } from 'react-redux'
+import { showModal } from '../../../actions'
+import AdvancedGasInputs from './advanced-gas-inputs.component'
+
+const mapDispatchToProps = dispatch => {
+  return {
+    showGasPriceInfoModal: modalName => dispatch(showModal({ name: 'GAS_PRICE_INFO_MODAL' })),
+    showGasLimitInfoModal: modalName => dispatch(showModal({ name: 'GAS_LIMIT_INFO_MODAL' })),
+  }
+}
+
+export default connect(null, mapDispatchToProps)(AdvancedGasInputs)
diff --git a/ui/app/components/gas-customization/advanced-gas-inputs/index.js b/ui/app/components/gas-customization/advanced-gas-inputs/index.js
new file mode 100644
index 000000000..bd8abaa3e
--- /dev/null
+++ b/ui/app/components/gas-customization/advanced-gas-inputs/index.js
@@ -0,0 +1 @@
+export { default } from './advanced-gas-inputs.container'
diff --git a/ui/app/components/gas-customization/advanced-gas-inputs/index.scss b/ui/app/components/gas-customization/advanced-gas-inputs/index.scss
new file mode 100644
index 000000000..50953cbe5
--- /dev/null
+++ b/ui/app/components/gas-customization/advanced-gas-inputs/index.scss
@@ -0,0 +1,133 @@
+.advanced-gas-inputs {
+  &__gas-edit-rows {
+    display: flex;
+    flex-flow: row;
+    justify-content: space-between;
+  }
+
+  &__gas-edit-row {
+    display: flex;
+    flex-flow: column;
+    width: 47.5%;
+
+    &__label {
+      color: #313B5E;
+      font-size: 12px;
+      display: flex;
+      justify-content: space-between;
+      align-items: center;
+
+      @media screen and (max-width: 576px) {
+        font-size: 10px;
+      }
+      
+      .fa-info-circle {
+        color: $silver;
+        margin-left: 10px;
+        cursor: pointer;
+      }
+
+      .fa-info-circle:hover {
+        color: $mid-gray;
+      }
+    }
+
+    &__error-text {
+      font-size: 12px;
+      color: red;
+    }
+
+    &__warning-text {
+      font-size: 12px;
+      color: orange;
+    }
+
+    &__input-wrapper {
+      position: relative;
+    }
+
+    &__input {
+      border: 1px solid $dusty-gray;
+      border-radius: 4px;
+      color: $mid-gray;
+      font-size: 16px;
+      height: 24px;
+      width: 100%;
+      padding-left: 8px;
+      padding-top: 2px;
+      margin-top: 7px;
+    }
+
+    &__input--error {
+       border: 1px solid $red;
+    }
+
+    &__input--warning {
+       border: 1px solid $orange;
+    }
+
+    &__input-arrows {
+      position: absolute;
+      top: 7px;
+      right: 0px;
+      width: 17px;
+      height: 24px;
+      border: 1px solid #dadada;
+      border-top-right-radius: 4px;
+      display: flex;
+      flex-direction: column;
+      color: #9b9b9b;
+      font-size: .8em;
+      border-bottom-right-radius: 4px;
+      cursor: pointer;
+
+      &__i-wrap {
+        width: 100%;
+        height: 100%;
+        display: flex;
+        justify-content: center;
+        cursor: pointer;
+      }
+
+      &__i-wrap:hover {
+        background: #4EADE7;
+        color: $white;
+      }
+
+      i:hover {
+        background: #4EADE7;
+      }
+
+      i {
+        font-size: 10px;
+      }
+    }
+
+    &__input-arrows--error {
+      border: 1px solid $red;
+    }
+
+    &__input-arrows--warning {
+      border: 1px solid $orange;
+    }
+
+    input[type="number"]::-webkit-inner-spin-button {
+      -webkit-appearance: none;
+      -moz-appearance: none;
+      display: none;
+    }
+
+    input[type="number"]:hover::-webkit-inner-spin-button {
+      -webkit-appearance: none;
+      -moz-appearance: none;
+      display: none;
+    }
+
+    &__gwei-symbol {
+      position: absolute;
+      top: 8px;
+      right: 10px;
+      color: $dusty-gray;
+    }
+  }
+}
\ No newline at end of file
diff --git a/ui/app/components/gas-customization/index.scss b/ui/app/components/gas-customization/index.scss
index e99d4e57f..b06c1d044 100644
--- a/ui/app/components/gas-customization/index.scss
+++ b/ui/app/components/gas-customization/index.scss
@@ -3,3 +3,5 @@
 @import './gas-modal-page-container/index';
 
 @import './gas-price-chart/index';
+
+@import './advanced-gas-inputs/index';
diff --git a/ui/app/components/modals/modal.js b/ui/app/components/modals/modal.js
index 32c860a7b..08bf205ef 100644
--- a/ui/app/components/modals/modal.js
+++ b/ui/app/components/modals/modal.js
@@ -230,6 +230,40 @@ const MODALS = {
     },
   },
 
+  GAS_PRICE_INFO_MODAL: {
+    contents: [
+      h(NotifcationModal, {
+        header: 'gasPriceNoDenom',
+        message: 'gasPriceInfoModalContent',
+      }),
+    ],
+    mobileModalStyle: {
+      width: '95%',
+      top: getEnvironmentType(window.location.href) === ENVIRONMENT_TYPE_POPUP ? '52vh' : '36.5vh',
+    },
+    laptopModalStyle: {
+      width: '449px',
+      top: 'calc(33% + 45px)',
+    },
+  },
+
+  GAS_LIMIT_INFO_MODAL: {
+    contents: [
+      h(NotifcationModal, {
+        header: 'gasLimit',
+        message: 'gasLimitInfoModalContent',
+      }),
+    ],
+    mobileModalStyle: {
+      width: '95%',
+      top: getEnvironmentType(window.location.href) === ENVIRONMENT_TYPE_POPUP ? '52vh' : '36.5vh',
+    },
+    laptopModalStyle: {
+      width: '449px',
+      top: 'calc(33% + 45px)',
+    },
+  },
+
   CONFIRM_RESET_ACCOUNT: {
     contents: h(ConfirmResetAccount),
     mobileModalStyle: {
diff --git a/ui/app/components/pages/confirm-transaction-base/confirm-transaction-base.component.js b/ui/app/components/pages/confirm-transaction-base/confirm-transaction-base.component.js
index 6bc415781..8d404aaca 100644
--- a/ui/app/components/pages/confirm-transaction-base/confirm-transaction-base.component.js
+++ b/ui/app/components/pages/confirm-transaction-base/confirm-transaction-base.component.js
@@ -11,6 +11,7 @@ import {
 import { CONFIRMED_STATUS, DROPPED_STATUS } from '../../../constants/transactions'
 import UserPreferencedCurrencyDisplay from '../../user-preferenced-currency-display'
 import { PRIMARY, SECONDARY } from '../../../constants/common'
+import AdvancedGasInputs from '../../gas-customization/advanced-gas-inputs'
 
 export default class ConfirmTransactionBase extends Component {
   static contextTypes = {
@@ -81,6 +82,11 @@ export default class ConfirmTransactionBase extends Component {
     titleComponent: PropTypes.node,
     valid: PropTypes.bool,
     warning: PropTypes.string,
+    advancedInlineGasShown: PropTypes.bool,
+    gasPrice: PropTypes.number,
+    gasLimit: PropTypes.number,
+    insufficientBalance: PropTypes.bool,
+    convertThenUpdateGasAndCalculate: PropTypes.func,
   }
 
   state = {
@@ -165,6 +171,11 @@ export default class ConfirmTransactionBase extends Component {
       hexTransactionFee,
       hexTransactionTotal,
       hideDetails,
+      advancedInlineGasShown,
+      gasPrice,
+      gasLimit,
+      insufficientBalance,
+      convertThenUpdateGasAndCalculate,
     } = this.props
 
     if (hideDetails) {
@@ -182,6 +193,18 @@ export default class ConfirmTransactionBase extends Component {
               headerTextClassName="confirm-detail-row__header-text--edit"
               onHeaderClick={() => this.handleEditGas()}
             />
+            {advancedInlineGasShown
+              ? <AdvancedGasInputs
+                updateCustomGasPrice={newGasPrice => convertThenUpdateGasAndCalculate({ gasPrice: newGasPrice, gasLimit })}
+                updateCustomGasLimit={newGasLimit => convertThenUpdateGasAndCalculate({ gasLimit: newGasLimit, gasPrice })}
+                customGasPrice={gasPrice}
+                customGasLimit={gasLimit}
+                insufficientBalance={insufficientBalance}
+                customPriceIsSafe={true}
+                isSpeedUp={false}
+              />
+              : null
+            }
           </div>
           <div>
             <ConfirmDetailRow
diff --git a/ui/app/components/pages/confirm-transaction-base/confirm-transaction-base.container.js b/ui/app/components/pages/confirm-transaction-base/confirm-transaction-base.container.js
index 1e2270432..98cde4b03 100644
--- a/ui/app/components/pages/confirm-transaction-base/confirm-transaction-base.container.js
+++ b/ui/app/components/pages/confirm-transaction-base/confirm-transaction-base.container.js
@@ -14,11 +14,17 @@ import {
   GAS_LIMIT_TOO_LOW_ERROR_KEY,
 } from '../../../constants/error-keys'
 import { getHexGasTotal } from '../../../helpers/confirm-transaction/util'
-import { isBalanceSufficient } from '../../send/send.utils'
+import {
+  convertGasPriceForInputs,
+  convertGasLimitForInputs,
+  decimalToHex,
+  decGWEIToHexWEI,
+} from '../../../helpers/conversions.util'
+import { isBalanceSufficient, calcGasTotal } from '../../send/send.utils'
 import { conversionGreaterThan } from '../../../conversion-util'
 import { MIN_GAS_LIMIT_DEC } from '../../send/send.constants'
 import { addressSlicer, valuesFor } from '../../../util'
-import { getMetaMaskAccounts } from '../../../selectors'
+import { getMetaMaskAccounts, getAdvancedInlineGasShown } from '../../../selectors'
 
 const casedContractMap = Object.keys(contractMap).reduce((acc, base) => {
   return {
@@ -47,7 +53,13 @@ const mapStateToProps = (state, props) => {
     nonce,
   } = confirmTransaction
   const { txParams = {}, lastGasPrice, id: transactionId } = txData
-  const { from: fromAddress, to: txParamsToAddress } = txParams
+  const {
+    from: fromAddress,
+    to: txParamsToAddress,
+    gasPrice,
+    gas: gasLimit,
+    value: amount,
+  } = txParams
   const accounts = getMetaMaskAccounts(state)
   const {
     conversionRate,
@@ -84,6 +96,13 @@ const mapStateToProps = (state, props) => {
   )
   const unapprovedTxCount = valuesFor(currentNetworkUnapprovedTxs).length
 
+  const insufficientBalance = !isBalanceSufficient({
+    amount,
+    gasTotal: calcGasTotal(gasLimit, gasPrice),
+    balance,
+    conversionRate,
+  })
+
   return {
     balance,
     fromAddress,
@@ -113,9 +132,13 @@ const mapStateToProps = (state, props) => {
     unapprovedTxCount,
     currentNetworkUnapprovedTxs,
     customGas: {
-      gasLimit: customGasLimit || txData.gasPrice,
-      gasPrice: customGasPrice || txData.gasLimit,
+      gasLimit: customGasLimit || gasPrice,
+      gasPrice: customGasPrice || gasLimit,
     },
+    advancedInlineGasShown: getAdvancedInlineGasShown(state),
+    gasPrice: convertGasPriceForInputs(gasPrice),
+    gasLimit: convertGasLimitForInputs(gasLimit),
+    insufficientBalance,
   }
 }
 
@@ -132,6 +155,12 @@ const mapDispatchToProps = dispatch => {
     updateGasAndCalculate: ({ gasLimit, gasPrice }) => {
       return dispatch(updateGasAndCalculate({ gasLimit, gasPrice }))
     },
+    convertThenUpdateGasAndCalculate: ({ gasLimit, gasPrice }) => {
+      return dispatch(updateGasAndCalculate({
+        gasLimit: decimalToHex(gasLimit),
+        gasPrice: decGWEIToHexWEI(gasPrice),
+      }))
+    },
     showRejectTransactionsConfirmationModal: ({ onSubmit, unapprovedTxCount }) => {
       return dispatch(showModal({ name: 'REJECT_TRANSACTIONS', onSubmit, unapprovedTxCount }))
     },
diff --git a/ui/app/components/pages/settings/settings-tab/settings-tab.component.js b/ui/app/components/pages/settings/settings-tab/settings-tab.component.js
index ce1f72407..1c02b2507 100644
--- a/ui/app/components/pages/settings/settings-tab/settings-tab.component.js
+++ b/ui/app/components/pages/settings/settings-tab/settings-tab.component.js
@@ -59,6 +59,8 @@ export default class SettingsTab extends PureComponent {
     nativeCurrency: PropTypes.string,
     useNativeCurrencyAsPrimaryCurrency: PropTypes.bool,
     setUseNativeCurrencyAsPrimaryCurrencyPreference: PropTypes.func,
+    setAdvancedInlineGasFeatureFlag: PropTypes.func,
+    advancedInlineGas: PropTypes.bool,
   }
 
   state = {
@@ -412,6 +414,32 @@ export default class SettingsTab extends PureComponent {
     )
   }
 
+  renderAdvancedGasInputInline () {
+    const { t } = this.context
+    const { advancedInlineGas, setAdvancedInlineGasFeatureFlag } = this.props
+
+    return (
+      <div className="settings-page__content-row">
+        <div className="settings-page__content-item">
+          <span>{ t('showAdvancedGasInline') }</span>
+          <div className="settings-page__content-description">
+            { t('showAdvancedGasInlineDescription') }
+          </div>
+        </div>
+        <div className="settings-page__content-item">
+          <div className="settings-page__content-item-col">
+            <ToggleButton
+              value={advancedInlineGas}
+              onToggle={value => setAdvancedInlineGasFeatureFlag(!value)}
+              activeLabel=""
+              inactiveLabel=""
+            />
+          </div>
+        </div>
+      </div>
+    )
+  }
+
   renderUsePrimaryCurrencyOptions () {
     const { t } = this.context
     const {
@@ -508,6 +536,7 @@ export default class SettingsTab extends PureComponent {
         { this.renderClearApproval() }
         { this.renderPrivacyOptIn() }
         { this.renderHexDataOptIn() }
+        { this.renderAdvancedGasInputInline() }
         { this.renderBlockieOptIn() }
       </div>
     )
diff --git a/ui/app/components/pages/settings/settings-tab/settings-tab.container.js b/ui/app/components/pages/settings/settings-tab/settings-tab.container.js
index 92f645438..49da0db12 100644
--- a/ui/app/components/pages/settings/settings-tab/settings-tab.container.js
+++ b/ui/app/components/pages/settings/settings-tab/settings-tab.container.js
@@ -25,6 +25,7 @@ const mapStateToProps = state => {
     featureFlags: {
       sendHexData,
       privacyMode,
+      advancedInlineGas,
     } = {},
     provider = {},
     currentLocale,
@@ -39,6 +40,7 @@ const mapStateToProps = state => {
     nativeCurrency,
     useBlockie,
     sendHexData,
+    advancedInlineGas,
     privacyMode,
     provider,
     useNativeCurrencyAsPrimaryCurrency,
@@ -54,6 +56,7 @@ const mapDispatchToProps = dispatch => {
     setUseBlockie: value => dispatch(setUseBlockie(value)),
     updateCurrentLocale: key => dispatch(updateCurrentLocale(key)),
     setHexDataFeatureFlag: shouldShow => dispatch(setFeatureFlag('sendHexData', shouldShow)),
+    setAdvancedInlineGasFeatureFlag: shouldShow => dispatch(setFeatureFlag('advancedInlineGas', shouldShow)),
     setPrivacyMode: enabled => dispatch(setFeatureFlag('privacyMode', enabled)),
     showResetAccountConfirmationModal: () => dispatch(showModal({ name: 'CONFIRM_RESET_ACCOUNT' })),
     setUseNativeCurrencyAsPrimaryCurrencyPreference: value => {
diff --git a/ui/app/components/send/send-content/send-gas-row/send-gas-row.component.js b/ui/app/components/send/send-content/send-gas-row/send-gas-row.component.js
index 8d305dd4f..50337e0bf 100644
--- a/ui/app/components/send/send-content/send-gas-row/send-gas-row.component.js
+++ b/ui/app/components/send/send-content/send-gas-row/send-gas-row.component.js
@@ -3,6 +3,7 @@ import PropTypes from 'prop-types'
 import SendRowWrapper from '../send-row-wrapper/'
 import GasFeeDisplay from './gas-fee-display/gas-fee-display.component'
 import GasPriceButtonGroup from '../../../gas-customization/gas-price-button-group'
+import AdvancedGasInputs from '../../../gas-customization/advanced-gas-inputs'
 
 export default class SendGasRow extends Component {
 
@@ -13,54 +14,94 @@ export default class SendGasRow extends Component {
     gasLoadingError: PropTypes.bool,
     gasTotal: PropTypes.string,
     showCustomizeGasModal: PropTypes.func,
+    setGasPrice: PropTypes.func,
+    setGasLimit: PropTypes.func,
     gasPriceButtonGroupProps: PropTypes.object,
     gasButtonGroupShown: PropTypes.bool,
+    advancedInlineGasShown: PropTypes.bool,
     resetGasButtons: PropTypes.func,
+    gasPrice: PropTypes.number,
+    gasLimit: PropTypes.number,
+    insufficientBalance: PropTypes.bool,
   }
 
   static contextTypes = {
     t: PropTypes.func,
   }
 
-  render () {
+  renderAdvancedOptionsButton () {
+    const { showCustomizeGasModal } = this.props
+    return <div className="advanced-gas-options-btn" onClick={() => showCustomizeGasModal()}>
+      { this.context.t('advancedOptions') }
+    </div>
+  }
+
+  renderContent () {
     const {
       conversionRate,
       convertedCurrency,
       gasLoadingError,
       gasTotal,
-      gasFeeError,
       showCustomizeGasModal,
       gasPriceButtonGroupProps,
       gasButtonGroupShown,
+      advancedInlineGasShown,
       resetGasButtons,
+      setGasPrice,
+      setGasLimit,
+      gasPrice,
+      gasLimit,
+      insufficientBalance,
     } = this.props
 
+    const gasPriceButtonGroup = <div>
+        <GasPriceButtonGroup
+          className="gas-price-button-group--small"
+          showCheck={false}
+          {...gasPriceButtonGroupProps}
+        />
+        { this.renderAdvancedOptionsButton() }
+      </div>
+    const gasFeeDisplay = <GasFeeDisplay
+      conversionRate={conversionRate}
+      convertedCurrency={convertedCurrency}
+      gasLoadingError={gasLoadingError}
+      gasTotal={gasTotal}
+      onReset={resetGasButtons}
+      onClick={() => showCustomizeGasModal()}
+    />
+    const advancedGasInputs = <div>
+      <AdvancedGasInputs
+        updateCustomGasPrice={newGasPrice => setGasPrice(newGasPrice, gasLimit)}
+        updateCustomGasLimit={newGasLimit => setGasLimit(newGasLimit, gasPrice)}
+        customGasPrice={gasPrice}
+        customGasLimit={gasLimit}
+        insufficientBalance={insufficientBalance}
+        customPriceIsSafe={true}
+        isSpeedUp={false}
+      />
+      { this.renderAdvancedOptionsButton() }
+     </div>
+
+    if (advancedInlineGasShown) {
+      return advancedGasInputs
+    } else if (gasButtonGroupShown) {
+      return gasPriceButtonGroup
+    } else {
+      return gasFeeDisplay
+    }
+  }
+
+  render () {
+    const { gasFeeError } = this.props
+
     return (
       <SendRowWrapper
         label={`${this.context.t('transactionFee')}:`}
         showError={gasFeeError}
         errorType={'gasFee'}
       >
-        {gasButtonGroupShown
-         ? <div>
-            <GasPriceButtonGroup
-              className="gas-price-button-group--small"
-              showCheck={false}
-              {...gasPriceButtonGroupProps}
-            />
-            <div className="advanced-gas-options-btn" onClick={() => showCustomizeGasModal()}>
-              { this.context.t('advancedOptions') }
-            </div>
-          </div>
-        : <GasFeeDisplay
-            conversionRate={conversionRate}
-            convertedCurrency={convertedCurrency}
-            gasLoadingError={gasLoadingError}
-            gasTotal={gasTotal}
-            onReset={resetGasButtons}
-            onClick={() => showCustomizeGasModal()}
-          />}
-
+        { this.renderContent() }
       </SendRowWrapper>
     )
   }
diff --git a/ui/app/components/send/send-content/send-gas-row/send-gas-row.container.js b/ui/app/components/send/send-content/send-gas-row/send-gas-row.container.js
index 977f8ab3c..b32928b75 100644
--- a/ui/app/components/send/send-content/send-gas-row/send-gas-row.container.js
+++ b/ui/app/components/send/send-content/send-gas-row/send-gas-row.container.js
@@ -4,32 +4,59 @@ import {
   getCurrentCurrency,
   getGasTotal,
   getGasPrice,
+  getGasLimit,
+  getSendAmount,
 } from '../../send.selectors.js'
 import {
+  isBalanceSufficient,
+  calcGasTotal,
+} from '../../send.utils.js'
+import {
   getBasicGasEstimateLoadingStatus,
   getRenderableEstimateDataForSmallButtonsFromGWEI,
   getDefaultActiveButtonIndex,
 } from '../../../../selectors/custom-gas'
 import {
+  decGWEIToHexWEI,
+  decimalToHex,
+  convertGasPriceForInputs,
+  convertGasLimitForInputs,
+} from '../../../../helpers/conversions.util'
+import {
   showGasButtonGroup,
 } from '../../../../ducks/send.duck'
 import {
   resetCustomData,
 } from '../../../../ducks/gas.duck'
 import { getGasLoadingError, gasFeeIsInError, getGasButtonGroupShown } from './send-gas-row.selectors.js'
-import { showModal, setGasPrice } from '../../../../actions'
+import { showModal, setGasPrice, setGasLimit, setGasTotal } from '../../../../actions'
+import { getAdvancedInlineGasShown, getCurrentEthBalance } from '../../../../selectors'
 import SendGasRow from './send-gas-row.component'
 
 export default connect(mapStateToProps, mapDispatchToProps, mergeProps)(SendGasRow)
 
 function mapStateToProps (state) {
   const gasButtonInfo = getRenderableEstimateDataForSmallButtonsFromGWEI(state)
-  const activeButtonIndex = getDefaultActiveButtonIndex(gasButtonInfo, getGasPrice(state))
+  const gasPrice = getGasPrice(state)
+  const activeButtonIndex = getDefaultActiveButtonIndex(gasButtonInfo, gasPrice)
+  const renderableGasPrice = convertGasPriceForInputs(gasPrice)
+  const renderableGasLimit = convertGasLimitForInputs(getGasLimit(state))
+
+  const gasTotal = getGasTotal(state)
+  const conversionRate = getConversionRate(state)
+  const balance = getCurrentEthBalance(state)
+
+  const insufficientBalance = !isBalanceSufficient({
+    amount: getSendAmount(state),
+    gasTotal,
+    balance,
+    conversionRate,
+  })
 
   return {
-    conversionRate: getConversionRate(state),
+    conversionRate,
     convertedCurrency: getCurrentCurrency(state),
-    gasTotal: getGasTotal(state),
+    gasTotal,
     gasFeeError: gasFeeIsInError(state),
     gasLoadingError: getGasLoadingError(state),
     gasPriceButtonGroupProps: {
@@ -39,13 +66,26 @@ function mapStateToProps (state) {
       gasButtonInfo,
     },
     gasButtonGroupShown: getGasButtonGroupShown(state),
+    advancedInlineGasShown: getAdvancedInlineGasShown(state),
+    gasPrice: renderableGasPrice,
+    gasLimit: renderableGasLimit,
+    insufficientBalance,
   }
 }
 
 function mapDispatchToProps (dispatch) {
   return {
     showCustomizeGasModal: () => dispatch(showModal({ name: 'CUSTOMIZE_GAS', hideBasic: true })),
-    setGasPrice: newPrice => dispatch(setGasPrice(newPrice)),
+    setGasPrice: (newPrice, gasLimit) => {
+      newPrice = decGWEIToHexWEI(newPrice)
+      dispatch(setGasPrice(newPrice))
+      dispatch(setGasTotal(calcGasTotal(gasLimit, newPrice)))
+    },
+    setGasLimit: (newLimit, gasPrice) => {
+      newLimit = decimalToHex(newLimit)
+      dispatch(setGasLimit(newLimit))
+      dispatch(setGasTotal(calcGasTotal(newLimit, gasPrice)))
+    },
     showGasButtonGroup: () => dispatch(showGasButtonGroup()),
     resetCustomData: () => dispatch(resetCustomData()),
   }
@@ -74,5 +114,6 @@ function mergeProps (stateProps, dispatchProps, ownProps) {
       dispatchSetGasPrice(gasButtonInfo[1].priceInHexWei)
       dispatchShowGasButtonGroup()
     },
+    setGasPrice: dispatchSetGasPrice,
   }
 }
diff --git a/ui/app/components/send/send-content/send-gas-row/tests/send-gas-row-container.test.js b/ui/app/components/send/send-content/send-gas-row/tests/send-gas-row-container.test.js
index f0c82e4f7..439f2ef6a 100644
--- a/ui/app/components/send/send-content/send-gas-row/tests/send-gas-row-container.test.js
+++ b/ui/app/components/send/send-content/send-gas-row/tests/send-gas-row-container.test.js
@@ -9,6 +9,8 @@ let mergeProps
 const actionSpies = {
   showModal: sinon.spy(),
   setGasPrice: sinon.spy(),
+  setGasTotal: sinon.spy(),
+  setGasLimit: sinon.spy(),
 }
 
 const sendDuckSpies = {
@@ -28,11 +30,26 @@ proxyquire('../send-gas-row.container.js', {
       return () => ({})
     },
   },
+  '../../../../selectors': {
+    getCurrentEthBalance: (s) => `mockCurrentEthBalance:${s}`,
+    getAdvancedInlineGasShown: (s) => `mockAdvancedInlineGasShown:${s}`,
+  },
   '../../send.selectors.js': {
     getConversionRate: (s) => `mockConversionRate:${s}`,
     getCurrentCurrency: (s) => `mockConvertedCurrency:${s}`,
     getGasTotal: (s) => `mockGasTotal:${s}`,
     getGasPrice: (s) => `mockGasPrice:${s}`,
+    getGasLimit: (s) => `mockGasLimit:${s}`,
+    getSendAmount: (s) => `mockSendAmount:${s}`,
+  },
+  '../../send.utils.js': {
+    isBalanceSufficient: ({
+      amount,
+      gasTotal,
+      balance,
+      conversionRate,
+    }) => `${amount}:${gasTotal}:${balance}:${conversionRate}`,
+    calcGasTotal: (gasLimit, gasPrice) => gasLimit + gasPrice,
   },
   './send-gas-row.selectors.js': {
     getGasLoadingError: (s) => `mockGasLoadingError:${s}`,
@@ -47,6 +64,12 @@ proxyquire('../send-gas-row.container.js', {
   },
   '../../../../ducks/send.duck': sendDuckSpies,
   '../../../../ducks/gas.duck': gasDuckSpies,
+  '../../../../helpers/conversions.util': {
+    convertGasPriceForInputs: str => str + '*',
+    convertGasLimitForInputs: str => str + '**',
+    decGWEIToHexWEI: str => '0x' + str + '000',
+    decimalToHex: str => '0x' + str,
+  },
 })
 
 describe('send-gas-row container', () => {
@@ -67,6 +90,10 @@ describe('send-gas-row container', () => {
           gasButtonInfo: `mockGasButtonInfo:mockState`,
         },
         gasButtonGroupShown: `mockGetGasButtonGroupShown:mockState`,
+        advancedInlineGasShown: 'mockAdvancedInlineGasShown:mockState',
+        gasLimit: 'mockGasLimit:mockState**',
+        gasPrice: 'mockGasPrice:mockState*',
+        insufficientBalance: false,
       })
     })
 
@@ -79,6 +106,7 @@ describe('send-gas-row container', () => {
     beforeEach(() => {
       dispatchSpy = sinon.spy()
       mapDispatchToPropsObject = mapDispatchToProps(dispatchSpy)
+      actionSpies.setGasTotal.resetHistory()
     })
 
     describe('showCustomizeGasModal()', () => {
@@ -94,10 +122,23 @@ describe('send-gas-row container', () => {
 
     describe('setGasPrice()', () => {
       it('should dispatch an action', () => {
-        mapDispatchToPropsObject.setGasPrice('mockNewPrice')
-        assert(dispatchSpy.calledOnce)
+        mapDispatchToPropsObject.setGasPrice('mockNewPrice', 'mockLimit')
+        assert(dispatchSpy.calledTwice)
         assert(actionSpies.setGasPrice.calledOnce)
-        assert.equal(actionSpies.setGasPrice.getCall(0).args[0], 'mockNewPrice')
+        assert.equal(actionSpies.setGasPrice.getCall(0).args[0], '0xmockNewPrice000')
+        assert(actionSpies.setGasTotal.calledOnce)
+        assert.equal(actionSpies.setGasTotal.getCall(0).args[0], 'mockLimit0xmockNewPrice000')
+      })
+    })
+
+    describe('setGasLimit()', () => {
+      it('should dispatch an action', () => {
+        mapDispatchToPropsObject.setGasLimit('mockNewLimit', 'mockPrice')
+        assert(dispatchSpy.calledTwice)
+        assert(actionSpies.setGasLimit.calledOnce)
+        assert.equal(actionSpies.setGasLimit.getCall(0).args[0], '0xmockNewLimit')
+        assert(actionSpies.setGasTotal.calledOnce)
+        assert.equal(actionSpies.setGasTotal.getCall(0).args[0], '0xmockNewLimitmockPrice')
       })
     })
 
diff --git a/ui/app/css/itcss/components/send.scss b/ui/app/css/itcss/components/send.scss
index 4372f275c..07ab04613 100644
--- a/ui/app/css/itcss/components/send.scss
+++ b/ui/app/css/itcss/components/send.scss
@@ -560,6 +560,7 @@
   &__form-field {
     flex: 1 1 auto;
     min-width: 0;
+    max-width: 277px;
 
     .currency-display {
       color: $tundora;
@@ -586,7 +587,7 @@
     font-family: Roboto;
     font-size: 16px;
     line-height: 22px;
-    width: 88px;
+    width: 95px;
     font-weight: 400;
     flex: 0 0 auto;
   }
@@ -934,6 +935,7 @@
   font-size: 14px;
   color: #2f9ae0;
   cursor: pointer;
+  margin-top: 16px;
 }
 
 .sliders-icon-container {
diff --git a/ui/app/ducks/confirm-transaction.duck.js b/ui/app/ducks/confirm-transaction.duck.js
index e228d2d39..c6e2c1be3 100644
--- a/ui/app/ducks/confirm-transaction.duck.js
+++ b/ui/app/ducks/confirm-transaction.duck.js
@@ -24,6 +24,7 @@ import {
 
 import { getSymbolAndDecimals } from '../token-util'
 import { conversionUtil } from '../conversion-util'
+import { addHexPrefix } from 'ethereumjs-util'
 
 // Actions
 const createActionType = action => `metamask/confirm-transaction/${action}`
@@ -256,6 +257,8 @@ export function setFetchingData (isFetching) {
 }
 
 export function updateGasAndCalculate ({ gasLimit, gasPrice }) {
+  gasLimit = addHexPrefix(gasLimit)
+  gasPrice = addHexPrefix(gasPrice)
   return (dispatch, getState) => {
     const { confirmTransaction: { txData } } = getState()
     const newTxData = {
diff --git a/ui/app/helpers/conversions.util.js b/ui/app/helpers/conversions.util.js
index 065d67e8e..d2aaeca33 100644
--- a/ui/app/helpers/conversions.util.js
+++ b/ui/app/helpers/conversions.util.js
@@ -120,3 +120,11 @@ export function hexWEIToDecGWEI (decGWEI) {
     toDenomination: 'GWEI',
   })
 }
+
+export function convertGasPriceForInputs (gasPriceInHexWEI) {
+  return Number(hexWEIToDecGWEI(gasPriceInHexWEI))
+}
+
+export function convertGasLimitForInputs (gasLimitInHexWEI) {
+  return parseInt(gasLimitInHexWEI, 16)
+}
diff --git a/ui/app/selectors.js b/ui/app/selectors.js
index 6e9bf6470..976342455 100644
--- a/ui/app/selectors.js
+++ b/ui/app/selectors.js
@@ -36,6 +36,7 @@ const selectors = {
   getCurrentEthBalance,
   getNetworkIdentifier,
   isBalanceCached,
+  getAdvancedInlineGasShown,
 }
 
 module.exports = selectors
@@ -230,3 +231,7 @@ function getTotalUnapprovedCount ({ metamask }) {
 function preferencesSelector ({ metamask }) {
   return metamask.preferences
 }
+
+function getAdvancedInlineGasShown (state) {
+  return Boolean(state.metamask.featureFlags.advancedInlineGas)
+}