From de0ee68ded274688badbd50c3f62c36a98150027 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Daniel=20Kn=C3=BCttel?= <daniel.knuettel@daknuett.eu>
Date: Thu, 18 Jan 2018 09:09:39 +0100
Subject: [PATCH] initial

---
 mathbot/__init__.py  |  0
 mathbot/__main__.py  | 26 ++++++++++++++++++++++++++
 mathbot/bot.py       | 42 ++++++++++++++++++++++++++++++++++++++++++
 mathbot/main.py      | 16 ++++++++++++++++
 mathbot/rendering.py | 27 +++++++++++++++++++++++++++
 mathbot/static.py    | 19 +++++++++++++++++++
 6 files changed, 130 insertions(+)
 create mode 100644 mathbot/__init__.py
 create mode 100644 mathbot/__main__.py
 create mode 100644 mathbot/bot.py
 create mode 100644 mathbot/main.py
 create mode 100644 mathbot/rendering.py
 create mode 100644 mathbot/static.py

diff --git a/mathbot/__init__.py b/mathbot/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/mathbot/__main__.py b/mathbot/__main__.py
new file mode 100644
index 0000000..51896e0
--- /dev/null
+++ b/mathbot/__main__.py
@@ -0,0 +1,26 @@
+from .main import main
+
+import sys, logging
+
+if( __name__ == "__main__"):
+
+
+	logging.basicConfig(format='%(asctime)s - %(name)s - %(levelname)s - %(message)s',
+			level=logging.INFO)
+
+	logger = logging.getLogger(__name__)
+
+	if(len(sys.argv) < 2):
+		print("E: missing bot api token file")
+		print("   usage:")
+		print("     {} <token file>".format(sys.argv[0]))
+		sys.exit(1)
+	try:
+		f = open(sys.argv[1])
+		token = f.read().strip()
+		f.close()
+	except:
+		print("E: failed to open and read token file")
+		sys.exit(1)
+
+	main(token)
diff --git a/mathbot/bot.py b/mathbot/bot.py
new file mode 100644
index 0000000..ac7e1e5
--- /dev/null
+++ b/mathbot/bot.py
@@ -0,0 +1,42 @@
+from telegram.ext import RegexHandler
+from .rendering import get_png
+from .static import static_content
+
+def handle_exception_in_get_png(bot, update, exception, text):
+	update.message.reply_text("**Error** while processing '__{}__'.\n\nException was: **{}**.".format(text, exception), parse_mode = "Markdown")
+
+def render_math(bot, update):
+	text = update.message.text[len("/rmath"):]
+	tex = "${}$".format(text)
+
+	try:
+		png = get_png(tex)
+	except Exception as e:
+		handle_exception_in_get_png(bot, update, e, tex)
+		return
+	
+	update.message.reply_photo(png, caption = "{}".format(text))
+
+def render_math_caption(bot, update):
+	text = update.message.text[len("/rmath"):]
+
+	if( not ("<" in text and ">" in text)):
+		update.message.reply_text("**Error**: missing caption seperators: < and >", parse_mode = "Markdown")
+		return
+
+	caption = text[text.index("<") + 1:text.index(">")]
+	text = text[text.index(">") + 1:]
+
+	tex = "${}$".format(text)
+
+	try:
+		png = get_png(tex)
+	except Exception as e:
+		handle_exception_in_get_png(bot, update, e, tex)
+		return
+	
+	update.message.reply_photo(png, caption = "{}\n\nLaTeX: {}".format(caption, text))
+
+def help(bot, update):
+	update.message.reply_text(static_content.help_text, parse_mode = "Markdown")
+
diff --git a/mathbot/main.py b/mathbot/main.py
new file mode 100644
index 0000000..2c8e100
--- /dev/null
+++ b/mathbot/main.py
@@ -0,0 +1,16 @@
+from telegram.ext import Updater, CommandHandler, RegexHandler
+from . import bot
+
+
+def main(api_token):
+	updater = Updater(api_token)
+
+	dispatcher = updater.dispatcher
+
+	dispatcher.add_handler(CommandHandler("help", bot.help))
+	dispatcher.add_handler(CommandHandler("rmath", bot.render_math))
+	dispatcher.add_handler(CommandHandler("rcmath", bot.render_math_caption))
+
+	updater.start_polling()
+
+	updater.idle()
diff --git a/mathbot/rendering.py b/mathbot/rendering.py
new file mode 100644
index 0000000..a41a0f1
--- /dev/null
+++ b/mathbot/rendering.py
@@ -0,0 +1,27 @@
+from sympy import preview
+from io import BytesIO
+import cairosvg, time, os
+
+
+def get_png(tex):
+	buf = BytesIO()
+	preview(tex, output = "svg", viewer = "BytesIO", outputbuffer = buf)
+	buf.seek(0)
+
+	fname = "/tmp/{}".format(time.time())
+
+	cairosvg.svg2png(bytestring=buf.read(), parent_widht=500, parent_height=500, write_to=fname)
+
+	buf.seek(0)
+
+	with open(fname, "rb") as fin:
+		buf.write(fin.read())
+	with open(fname, "rb") as fin:
+		with open("test.png", "wb") as fout:
+			fout.write(fin.read())
+		
+	os.unlink(fname)
+
+	buf.seek(0)
+
+	return buf
diff --git a/mathbot/static.py b/mathbot/static.py
new file mode 100644
index 0000000..64cf492
--- /dev/null
+++ b/mathbot/static.py
@@ -0,0 +1,19 @@
+
+_help_text = '''
+**RMathBot** -- render LaTeX math commands
+
+Usage:
+
+- `/help` print this help message and exit
+- `/rmath LATEX` render __LATEX__ and return the resulting PNG with the input text
+- `/rcmath <CAPTION> LATEX` render __LATEX__ and return the resulting PNG with the input text
+  and caption __CAPTION__
+
+
+'''
+
+class StaticContent(object):
+	def __init__(self):
+		self.help_text = _help_text
+
+static_content = StaticContent()