Merge pull request #2838 from nextcloud/refactor/text-objectv1.3.0-beta3

Abstract text into an object with known format

11 files changed, 401 insertions, 272 deletions

diff --git a/src/ReplyBuilder.js b/src/ReplyBuilder.js
index de477e9d7..4422f709e 100644
--- a/src/ReplyBuilder.js
+++ b/src/ReplyBuilder.js
@@ -23,28 +23,39 @@
 import moment from '@nextcloud/moment'
 import negate from 'lodash/fp/negate'
 
+import {html} from './util/text'
+
+/**
+ * @param {Text} original
+ * @param {object} from
+ * @param {Number} date
+ * @return {Text}
+ */
 export const buildReplyBody = (original, from, date) => {
 	const start = '<p></p><p></p>'
-	const body = '<br>&gt; ' + original.replace(/\n/g, '<br>&gt; ')
 
-	if (from) {
-		const dateString = moment.unix(date).format('LLL')
-		return `${start}"${from.label}" ${from.email} – ${dateString}` + body
-	} else {
-		return `${start}${body}`
+	switch (original.format) {
+		case 'plain':
+			const plainBody = '<br>&gt; ' + original.value.replace(/\n/g, '<br>&gt; ')
+
+			if (from) {
+				const dateString = moment.unix(date).format('LLL')
+				return html(`${start}"${from.label}" ${from.email} – ${dateString}` + plainBody)
+			} else {
+				return html(`${start}${plainBody}`)
+			}
+		case 'html':
+			const htmlBody = `<blockquote>${original.value}</blockquote>`
+
+			if (from) {
+				const dateString = moment.unix(date).format('LLL')
+				return html(`${start}"${from.label}" ${from.email} – ${dateString}<br>${htmlBody}`)
+			} else {
+				return html(`${start}${htmlBody}`)
+			}
 	}
-}
-
-export const buildHtmlReplyBody = (original, from, date) => {
-	const start = `<p></p><p></p>`
-	const body = `<blockquote>${original}</blockquote>`
 
-	if (from) {
-		const dateString = moment.unix(date).format('LLL')
-		return `${start}"${from.label}" ${from.email} – ${dateString}<br>${body}`
-	} else {
-		return `${start}${body}`
-	}
+	throw new Error(`can't build a reply for the format ${original.format}`)
 }
 
 const RecipientType = Object.seal({
diff --git a/src/components/Composer.vue b/src/components/Composer.vue
index 00ee4b2b1..f8a4b8687 100644
--- a/src/components/Composer.vue
+++ b/src/components/Composer.vue
@@ -199,7 +199,7 @@ import Vue from 'vue'
 
 import ComposerAttachments from './ComposerAttachments'
 import {findRecipient} from '../service/AutocompleteService'
-import {htmlToText, textToSimpleHtml} from '../util/HtmlHelper'
+import {detect, html, toHtml} from '../util/text'
 import Loading from './Loading'
 import logger from '../logger'
 import TextEditor from './TextEditor'
@@ -249,8 +249,8 @@ export default {
 			default: '',
 		},
 		body: {
-			type: String,
-			default: '',
+			type: Object,
+			default: () => html(''),
 		},
 		draft: {
 			type: Function,
@@ -260,10 +260,6 @@ export default {
 			type: Function,
 			required: true,
 		},
-		isPlainText: {
-			type: Boolean,
-			default: true,
-		},
 	},
 	data() {
 		return {
@@ -272,21 +268,21 @@ export default {
 			autocompleteRecipients: this.to.concat(this.cc).concat(this.bcc),
 			newRecipients: [],
 			subjectVal: this.subject,
-			bodyVal: this.isPlainText ? textToSimpleHtml(this.body) : this.body,
+			bodyVal: toHtml(this.body).value,
 			attachments: [],
 			noReply: this.to.some((to) => to.email.startsWith('noreply@') || to.email.startsWith('no-reply@')),
 			submitButtonTitle: t('mail', 'Send'),
 			draftsPromise: Promise.resolve(),
 			attachmentsPromise: Promise.resolve(),
 			savingDraft: undefined,
-			saveDraftDebounced: debounce(700)(this.saveDraft),
+			saveDraftDebounced: debounce(700, this.saveDraft),
 			state: STATES.EDITING,
 			errorText: undefined,
 			STATES,
 			selectTo: this.to,
 			selectCc: this.cc,
 			selectBcc: this.bcc,
-			editorPlainText: this.isPlainText,
+			editorPlainText: false,
 			bus: new Vue(),
 		}
 	},
@@ -302,9 +298,6 @@ export default {
 		isReply() {
 			return this.to.length > 0
 		},
-		noSubject() {
-			return this.subjectVal === '' && this.bodyVal !== ''
-		},
 		canSend() {
 			return this.selectTo.length > 0 || this.selectCc.length > 0 || this.selectBcc.length > 0
 		},
@@ -350,7 +343,7 @@ export default {
 			}
 		},
 		initBody() {
-			this.bodyVal = this.bodyWithSignature(this.selectedAlias, this.bodyVal)
+			this.bodyVal = this.bodyWithSignature(this.selectedAlias, this.bodyVal).value
 		},
 		recipientToRfc822(recipient) {
 			if (recipient.email === recipient.label) {
@@ -375,7 +368,7 @@ export default {
 				bcc: this.selectBcc.map(this.recipientToRfc822).join(', '),
 				draftUID: uid,
 				subject: this.subjectVal,
-				body: this.editorPlainText ? htmlToText(this.bodyVal) : this.bodyVal,
+				body: html(this.bodyVal),
 				attachments: this.attachments,
 				folderId: this.replyTo ? this.replyTo.folderId : undefined,
 				messageId: this.replyTo ? this.replyTo.messageId : undefined,
@@ -513,10 +506,12 @@ export default {
 		},
 		bodyWithSignature(alias, body) {
 			if (!alias || !alias.signature) {
-				return body
+				return html(body)
 			}
 
-			return `${body} <br>--<br> ${textToSimpleHtml(alias.signature)}`
+			return html(body)
+				.append('<br>--<br>')
+				.append(toHtml(detect(alias.signature)))
 		},
 	},
 }
diff --git a/src/components/NewMessageDetail.vue b/src/components/NewMessageDetail.vue
index 39be8ae6c..cc0f55b3c 100644
--- a/src/components/NewMessageDetail.vue
+++ b/src/components/NewMessageDetail.vue
@@ -18,7 +18,6 @@
 			:body="composerData.body"
 			:draft="saveDraft"
 			:send="sendMessage"
-			:is-plain-text="composerData.isPlainText"
 		/>
 	</AppContentDetails>
 </template>
@@ -30,14 +29,14 @@ import {generateUrl} from '@nextcloud/router'
 
 import {
 	buildForwardSubject,
-	buildHtmlReplyBody,
 	buildReplyBody,
 	buildReplySubject,
 	buildRecipients as buildReplyRecipients,
 } from '../ReplyBuilder'
 import Composer from './Composer'
-import {getRandomMessageErrorMessage} from '../util/ErrorMessageFactory'
 import Error from './Error'
+import {getRandomMessageErrorMessage} from '../util/ErrorMessageFactory'
+import {detect, html, plain, toPlain} from '../util/text'
 import Loading from './Loading'
 import Logger from '../logger'
 import {saveDraft, sendMessage} from '../service/MessageService'
@@ -69,8 +68,7 @@ export default {
 					cc: this.draft.cc,
 					bcc: this.draft.bcc,
 					subject: this.draft.subject,
-					body: this.draft.body,
-					isPlainText: !this.draft.hasHtmlBody,
+					body: this.draft.hasHtmlBody ? html(this.draft.body) : plain(this.draft.body),
 				}
 			} else if (this.$route.query.uid !== undefined) {
 				// Forward or reply to a message
@@ -118,7 +116,7 @@ export default {
 					to: this.stringToRecipients(this.$route.query.to),
 					cc: this.stringToRecipients(this.$route.query.cc),
 					subject: this.$route.query.subject || '',
-					body: this.$route.query.body || '',
+					body: this.$route.query.body ? detect(this.$route.query.body) : html(''),
 				}
 			}
 		},
@@ -193,53 +191,47 @@ export default {
 					}
 				})
 		},
-		fetchOriginalMessage(uid) {
+		async fetchOriginalMessage(uid) {
 			this.loading = true
 			this.error = undefined
 			this.errorMessage = ''
 
-			this.$store
-				.dispatch('fetchMessage', uid)
-				.then((message) => {
-					if (message.uid !== this.$route.query.uid) {
-						Logger.debug("User navigated away, loaded original message won't be used")
-						return
-					}
+			try {
+				const message = await this.$store.dispatch('fetchMessage', uid)
+				if (message.uid !== this.$route.query.uid) {
+					Logger.debug("User navigated away, loaded original message won't be used")
+					return
+				}
 
-					Logger.debug('original message fetched', {message})
-					this.original = message
+				Logger.debug('original message fetched', {message})
+				this.original = message
 
-					if (message.hasHtmlBody) {
-						Logger.debug('original message has HTML body')
-						return Axios.get(
-							generateUrl('/apps/mail/api/accounts/{accountId}/folders/{folderId}/messages/{id}/html', {
-								accountId: message.accountId,
-								folderId: message.folderId,
-								id: message.id,
-							})
-						).then((resp) => resp.data)
-					} else {
-						return message.body
-					}
-				})
-				.then((body) => {
-					this.originalBody = body
+				let body = plain(message.body || '')
+				if (message.hasHtmlBody) {
+					Logger.debug('original message has HTML body')
+					const resp = await Axios.get(
+						generateUrl('/apps/mail/api/accounts/{accountId}/folders/{folderId}/messages/{id}/html', {
+							accountId: message.accountId,
+							folderId: message.folderId,
+							id: message.id,
+						})
+					)
 
+					body = html(resp.data)
+				}
+				this.originalBody = body
+			} catch (error) {
+				Logger.error('could not load original message ' + uid, {error})
+				if (error.isError) {
+					this.errorMessage = t('mail', 'Could not load original message')
+					this.error = error
 					this.loading = false
-				})
-				.catch((error) => {
-					Logger.error('could not load original message ' + uid, {error})
-					if (error.isError) {
-						this.errorMessage = t('mail', 'Could not load original message')
-						this.error = error
-						this.loading = false
-					}
-				})
+				}
+			} finally {
+				this.loading = false
+			}
 		},
 		getForwardReplyBody() {
-			if (this.original.hasHtmlBody) {
-				return buildHtmlReplyBody(this.originalBody, this.original.from[0], this.original.dateInt)
-			}
 			return buildReplyBody(this.originalBody, this.original.from[0], this.original.dateInt)
 		},
 		saveDraft(data) {
@@ -247,7 +239,11 @@ export default {
 				Logger.debug('draft data does not have a draftUID, adding one')
 				data.draftUID = this.draft.id
 			}
-			return saveDraft(data.account, data).then(({uid}) => {
+			const dataForServer = {
+				...data,
+				body: data.isHtml ? data.body.value : toPlain(data.body).value,
+			}
+			return saveDraft(data.account, dataForServer).then(({uid}) => {
 				if (this.draft === undefined) {
 					return uid
 				}
@@ -275,7 +271,11 @@ export default {
 			})
 		},
 		sendMessage(data) {
-			return sendMessage(data.account, data)
+			const dataForServer = {
+				...data,
+				body: data.isHtml ? data.body.value : toPlain(data.body).value,
+			}
+			return sendMessage(data.account, dataForServer)
 		},
 	},
 }
diff --git a/src/components/SignatureSettings.vue b/src/components/SignatureSettings.vue
index fe0f2e4eb..0df62c1c3 100644
--- a/src/components/SignatureSettings.vue
+++ b/src/components/SignatureSettings.vue
@@ -47,7 +47,7 @@
 <script>
 import logger from '../logger'
 import TextEditor from './TextEditor'
-import {textToSimpleHtml} from '../util/HtmlHelper'
+import {detect, html, toHtml} from '../util/text'
 import Vue from 'vue'
 
 export default {
@@ -62,17 +62,9 @@ export default {
 		},
 	},
 	data() {
-		let signature = this.account.signature || ''
-
-		if ((signature.includes('\n') || signature.includes('\r')) && !signature.includes('>')) {
-			// Looks like a plain text signature -> convert to HTML
-			signature = textToSimpleHtml(signature)
-			logger.info('Converted plain text signature to HTML')
-		}
-
 		return {
 			loading: false,
-			signature,
+			signature: this.account.signature ? toHtml(detect(this.account.signature)) : html(''),
 			bus: new Vue(),
 		}
 	},
diff --git a/src/components/TextEditor.vue b/src/components/TextEditor.vue
index 5cc5a79b9..af79f7c2d 100644
--- a/src/components/TextEditor.vue
+++ b/src/components/TextEditor.vue
@@ -45,7 +45,6 @@ import ParagraphPlugin from '@ckeditor/ckeditor5-paragraph/src/paragraph'
 import {getLanguage} from '@nextcloud/l10n'
 
 import logger from '../logger'
-import {htmlToText} from '../util/HtmlHelper'
 
 export default {
 	name: 'TextEditor',
diff --git a/src/service/MessageService.js b/src/service/MessageService.js
index 0be155b33..f9cb85ddc 100644
--- a/src/service/MessageService.js
+++ b/src/service/MessageService.js
@@ -121,12 +121,12 @@ export function fetchMessage(accountId, folderId, id) {
 		})
 }
 
-export function saveDraft(accountId, data) {
+export async function saveDraft(accountId, data) {
 	const url = generateUrl('/apps/mail/api/accounts/{accountId}/draft', {
 		accountId,
 	})
 
-	return axios.post(url, data).then((resp) => resp.data)
+	return (await axios.post(url, data)).data
 }
 
 export function sendMessage(accountId, data) {
diff --git a/src/tests/unit/ReplyBuilder.spec.js b/src/tests/unit/ReplyBuilder.spec.js
index 7191dc309..1534826b9 100644
--- a/src/tests/unit/ReplyBuilder.spec.js
+++ b/src/tests/unit/ReplyBuilder.spec.js
@@ -21,20 +21,21 @@
  */
 
 import {buildReplyBody, buildRecipients, buildReplySubject} from '../../ReplyBuilder'
+import {html, plain} from '../../util/text'
 
 describe('ReplyBuilder', () => {
 	it('creates a reply body without any sender', () => {
-		const body = 'Newsletter\nhello\ncheers'
-		const expectedReply = '<p></p><p></p><br>&gt; Newsletter<br>&gt; hello<br>&gt; cheers'
+		const body = plain('Newsletter\nhello\ncheers')
+		const expectedReply = html('<p></p><p></p><br>&gt; Newsletter<br>&gt; hello<br>&gt; cheers')
 
 		const replyBody = buildReplyBody(body)
 
-		expect(replyBody).to.equal(expectedReply)
+		expect(replyBody).to.deep.equal(expectedReply)
 	})
 
 	it('creates a reply body', () => {
-		const body = 'Newsletter\nhello'
-		const expectedReply = '<p></p><p></p>"Test User" test@user.ru – November 5, 2018 '
+		const body = plain('Newsletter\nhello')
+		const expectedReply = html('<p></p><p></p>"Test User" test@user.ru – November 5, 2018 ')
 
 		const replyBody = buildReplyBody(
 			body,
@@ -45,7 +46,7 @@ describe('ReplyBuilder', () => {
 			1541426237
 		)
 
-		expect(replyBody.startsWith(expectedReply)).to.be.true
+		expect(replyBody.value.startsWith(expectedReply.value)).to.be.true
 	})
 
 	let envelope
diff --git a/src/tests/unit/util/HtmlHelper.spec.js b/src/tests/unit/util/HtmlHelper.spec.js
deleted file mode 100644
index f3bafd93a..000000000
--- a/src/tests/unit/util/HtmlHelper.spec.js
+++ /dev/null
@@ -1,133 +0,0 @@
-/**
- * @copyright 2017 Christoph Wurst <christoph@winzerhof-wurst.at>
- *
- * @author 2017 Christoph Wurst <christoph@winzerhof-wurst.at>
- *
- * @license GNU AGPL version 3 or any later version
- *
- * This program is free software: you can redistribute it and/or modify
- * it under the terms of the GNU Affero General Public License as
- * published by the Free Software Foundation, either version 3 of the
- * License, or (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU Affero General Public License for more details.
- *
- * You should have received a copy of the GNU Affero General Public License
- * along with this program.  If not, see <http://www.gnu.org/licenses/>.
- *
- */
-
-import {htmlToText} from '../../../util/HtmlHelper'
-
-describe('HtmlHelper', () => {
-	it('preserves breaks', () => {
-		const html = 'line1<br>line2'
-		const expected = 'line1\nline2'
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-
-	it('breaks on divs', () => {
-		const html = '<div>one</div><div>two</div>'
-		const expected = 'one\ntwo'
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-
-	it('produces a line break for each ending div element', () => {
-		const html = '<div>' + '    <div>' + '        line1' + '    </div>' + '</div>' + '<div>line2</div>'
-		const expected = ' line1\n\nline2'
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-
-	it('converts blocks to text', () => {
-		const html = '<div>hello</div>'
-		const expected = 'hello'
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-
-	it('converts paragraph to text', () => {
-		const html = '<p>hello</p>'
-		const expected = 'hello'
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-
-	it('converts paragraphs to text', () => {
-		const html = '<p>hello</p><p>world</p>'
-		const expected = 'hello\n\nworld'
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-
-	it('converts lists to text', () => {
-		const html = '<ul><li>one</li><li>two</li><li>three</li></ul>'
-		const expected = ' * one\n * two\n * three'
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-
-	it('converts deeply nested elements to text', () => {
-		const html =
-			'<html>' +
-			'<body><p>Hello!</p><p>this <i>is</i> <b>some</b> random <strong>text</strong></p></body>' +
-			'</html>'
-		const expected = 'Hello!\n\nthis is some random text'
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-
-	it('does not leak internal redirection URLs', () => {
-		const html = '<a href="https://localhost/apps/mail/redirect?src=domain.tld">domain.tld</a>'
-		const expected = 'domain.tld'
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-
-	it('preserves quotes', () => {
-		const html = `<blockquote><div><b>yes.</b></div><div><br /></div><div>Am Montag, den 21.10.2019, 16:51 +0200 schrieb Christoph Wurst:</div><blockquote style="margin:0 0 0 .8ex;border-left:2px #729fcf solid;padding-left:1ex;"><div>ok cool</div><div><br /></div><div>Am Montag, den 21.10.2019, 16:51 +0200 schrieb Christoph Wurst:</div><blockquote style="margin:0 0 0 .8ex;border-left:2px #729fcf solid;padding-left:1ex;"><div>Hello</div><div><br /></div><div>this is some t<i>e</i>xt</div><div><br /></div><div>yes</div><div><br /></div><div>cheers</div><br></blockquote><br></blockquote></blockquote>`
-		const expected = `> yes.
->
-> Am Montag, den 21.10.2019, 16:51 +0200 schrieb Christoph Wurst:
-> > ok cool
-> >
-> > Am Montag, den 21.10.2019, 16:51 +0200 schrieb Christoph Wurst:
-> > > Hello
-> > >
-> > > this is some text
-> > >
-> > > yes
-> > >
-> > > cheers
-> > >
-> > >
-> >`
-
-		const actual = htmlToText(html)
-
-		expect(actual).to.equal(expected)
-	})
-})
diff --git a/src/tests/unit/util/text.spec.js b/src/tests/unit/util/text.spec.js
new file mode 100644
index 000000000..97e1c4a39
--- /dev/null
+++ b/src/tests/unit/util/text.spec.js
@@ -0,0 +1,156 @@
+/**
+ * @copyright 2017 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @author 2017 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+import {html, toPlain, plain, detect} from '../../../util/text'
+
+describe('text', () => {
+	describe('toPlain', () => {
+		it('preserves breaks', () => {
+			const source = html('line1<br>line2')
+			const expected = plain('line1\nline2')
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+
+		it('breaks on divs', () => {
+			const source = html('<div>one</div><div>two</div>')
+			const expected = plain('one\ntwo')
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+
+		it('produces a line break for each ending div element', () => {
+			const source = html('<div>' + '    <div>' + '        line1' + '    </div>' + '</div>' + '<div>line2</div>')
+			const expected = plain(' line1\n\nline2')
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+
+		it('converts blocks to text', () => {
+			const source = html('<div>hello</div>')
+			const expected = plain('hello')
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+
+		it('converts paragraph to text', () => {
+			const source = html('<p>hello</p>')
+			const expected = plain('hello')
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+
+		it('converts paragraphs to text', () => {
+			const source = html('<p>hello</p><p>world</p>')
+			const expected = plain('hello\n\nworld')
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+
+		it('converts lists to text', () => {
+			const source = html('<ul><li>one</li><li>two</li><li>three</li></ul>')
+			const expected = plain(' * one\n * two\n * three')
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+
+		it('converts deeply nested elements to text', () => {
+			const source = html(
+				'<html>' +
+					'<body><p>Hello!</p><p>this <i>is</i> <b>some</b> random <strong>text</strong></p></body>' +
+					'</html>'
+			)
+			const expected = plain('Hello!\n\nthis is some random text')
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+
+		it('does not leak internal redirection URLs', () => {
+			const source = html('<a href="https://localhost/apps/mail/redirect?src=domain.tld">domain.tld</a>')
+			const expected = plain('domain.tld')
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+
+		it('preserves quotes', () => {
+			const source = html(
+				`<blockquote><div><b>yes.</b></div><div><br /></div><div>Am Montag, den 21.10.2019, 16:51 +0200 schrieb Christoph Wurst:</div><blockquote style="margin:0 0 0 .8ex;border-left:2px #729fcf solid;padding-left:1ex;"><div>ok cool</div><div><br /></div><div>Am Montag, den 21.10.2019, 16:51 +0200 schrieb Christoph Wurst:</div><blockquote style="margin:0 0 0 .8ex;border-left:2px #729fcf solid;padding-left:1ex;"><div>Hello</div><div><br /></div><div>this is some t<i>e</i>xt</div><div><br /></div><div>yes</div><div><br /></div><div>cheers</div><br></blockquote><br></blockquote></blockquote>`
+			)
+			const expected = plain(`> yes.
+>
+> Am Montag, den 21.10.2019, 16:51 +0200 schrieb Christoph Wurst:
+> > ok cool
+> >
+> > Am Montag, den 21.10.2019, 16:51 +0200 schrieb Christoph Wurst:
+> > > Hello
+> > >
+> > > this is some text
+> > >
+> > > yes
+> > >
+> > > cheers
+> > >
+> > >
+> >`)
+
+			const actual = toPlain(source)
+
+			expect(actual).to.deep.equal(expected)
+		})
+	})
+
+	describe('detect', () => {
+		it('detects plain text', () => {
+			const text = 'hello world\nsecond line'
+
+			const detected = detect(text)
+
+			expect(detected).to.deep.equal(plain(text))
+		})
+
+		it('detects html', () => {
+			const text = '<p>hello world</p><p>second line</p>'
+
+			const detected = detect(text)
+
+			expect(detected).to.deep.equal(html(text))
+		})
+	})
+})
diff --git a/src/util/HtmlHelper.js b/src/util/HtmlHelper.js
deleted file mode 100644
index a1206d421..000000000
--- a/src/util/HtmlHelper.js
+++ /dev/null
@@ -1,41 +0,0 @@
-/**
- * Mail
- *
- * This file is licensed under the Affero General Public License version 3 or
- * later. See the COPYING file.
- *
- * @author Christoph Wurst <christoph@winzerhof-wurst.at>
- * @copyright Christoph Wurst 2016
- */
-
-import {fromString} from 'html-to-text'
-
-export const htmlToText = (html) => {
-	const withBlockBreaks = html.replace(/<\/div>/gi, '</div><br>')
-
-	const text = fromString(withBlockBreaks, {
-		noLinkBrackets: true,
-		ignoreHref: true,
-		ignoreImage: true,
-		wordwrap: false,
-		format: {
-			blockquote: function (element, fn, options) {
-				return fn(element.children, options)
-					.replace(/\n\n\n/g, '\n\n') // remove triple line breaks
-					.replace(/^/gm, '> ') // add > quotation to each line
-			},
-			paragraph: function (element, fn, options) {
-				return fn(element.children, options) + '\n'
-			},
-		},
-	})
-
-	return text
-		.replace(/\n\n\n/g, '\n\n') // remove triple line breaks
-		.replace(/^[\n\r]+/g, '') // trim line breaks at beginning and end
-		.replace(/ $/gm, '') // trim white space at end of each line
-}
-
-export const textToSimpleHtml = (text) => {
-	return text.replace(/([^>\r\n]?)(\r\n|\n\r|\r|\n)/g, '$1<br>$2')
-}
diff --git a/src/util/text.js b/src/util/text.js
new file mode 100644
index 000000000..f1b7f245a
--- /dev/null
+++ b/src/util/text.js
@@ -0,0 +1,149 @@
+/*
+ * @copyright 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @author 2020 Christoph Wurst <christoph@winzerhof-wurst.at>
+ *
+ * @license GNU AGPL version 3 or any later version
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of the
+ * License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+import {curry} from 'ramda'
+import {fromString} from 'html-to-text'
+
+/**
+ * @type {Text}
+ */
+class Text {
+	constructor(format, value) {
+		this.format = format
+		this.value = value
+	}
+
+	/**
+	 * @param {Text} other
+	 * @return {Text}
+	 */
+	append(other) {
+		if (this.format !== other.format) {
+			throw new Error("can't append two different formats")
+		}
+
+		return new Text(this.format, this.value + other.value)
+	}
+}
+
+/**
+ * @param {string} format
+ * @param {string} value
+ *
+ * @return {object}
+ */
+const wrap = curry((format, value) => {
+	return new Text(format, value)
+})
+
+/**
+ * @param {string} value
+ * @return {Text}
+ */
+export const plain = wrap('plain')
+
+/**
+ * @function
+ * @param {string} value
+ * @return {Text}
+ */
+export const html = wrap('html')
+
+export const detect = (str) => {
+	if (!str.includes('>')) {
+		return plain(str)
+	} else {
+		return html(str)
+	}
+}
+
+/**
+ * @function
+ * @param {string} format
+ * @param {Text} text
+ */
+const isFormat = curry((format, text) => {
+	return text.format === format
+})
+
+/**
+ * @function
+ * @param {Text} text
+ * @return {bool}
+ */
+export const isPlain = isFormat('plain')
+
+/**
+ * @function
+ * @param {Text} text
+ * @return {bool}
+ */
+export const isHtml = isFormat('html')
+
+/**
+ * @param {Text} text
+ * @return {Text}
+ */
+export const toPlain = (text) => {
+	if (text.format === 'plain') {
+		return text
+	}
+	const withBlockBreaks = text.value.replace(/<\/div>/gi, '</div><br>')
+
+	const converted = fromString(withBlockBreaks, {
+		noLinkBrackets: true,
+		ignoreHref: true,
+		ignoreImage: true,
+		wordwrap: false,
+		format: {
+			blockquote: function (element, fn, options) {
+				return fn(element.children, options)
+					.replace(/\n\n\n/g, '\n\n') // remove triple line breaks
+					.replace(/^/gm, '> ') // add > quotation to each line
+			},
+			paragraph: function (element, fn, options) {
+				return fn(element.children, options) + '\n\n'
+			},
+		},
+	})
+
+	return plain(
+		converted
+			.replace(/\n\n\n/g, '\n\n') // remove triple line breaks
+			.replace(/^[\n\r]+/g, '') // trim line breaks at beginning and end
+			.replace(/ $/gm, '') // trim white space at end of each line
+	)
+}
+
+/**
+ * @param {Text} text
+ * @return {Text}
+ */
+export const toHtml = (text) => {
+	if (text.format === 'html') {
+		return text
+	}
+	if (text.format === 'plain') {
+		return html(text.value.replace(/([^>\r\n]?)(\r\n|\n\r|\r|\n)/g, '$1<br>$2'))
+	}
+
+	throw new Error(`Unknown format ${text.format}`)
+}