#!/usr/bin/env bash

#
# Steps:
#
# 1. Download corresponding html file for some README.md:
# curl -s 1ドル
#
# 2. Discard rows where no substring 'user-content-' (github's markup):
# awk '/user-content-/ { ...
#
# 3.1 Get last number in each row like ' ... </span></a>sitemap.js</h1'.
# It's a level of the current header:
# substr(0,ドル length(0ドル), 1)
#
# 3.2 Get level from 3.1 and insert corresponding number of spaces before '*':
# sprintf("%*s", substr(0,ドル length(0ドル), 1)*3, " ")
#
# 4. Find head's text and insert it inside "* [ ... ]":
# substr(0,ドル match(0,ドル /a>.*<\/h/)+2, RLENGTH-5)
#
# 5. Find anchor and insert it inside "(...)":
# substr(0,ドル match(0,ドル "href=\"[^\"]+?\" ")+6, RLENGTH-8)
#

gh_toc_version="0.4.8"

gh_user_agent="gh-md-toc v$gh_toc_version"

#
# Download rendered into html README.md by its url.
#
#
gh_toc_load() {
 local gh_url=1ドル

 if type curl &>/dev/null; then
curl --user-agent "$gh_user_agent" -s "$gh_url"
 elif type wget &>/dev/null; then
wget --user-agent="$gh_user_agent" -qO- "$gh_url"
 else
echo "Please, install 'curl' or 'wget' and try again."
 exit 1
 fi
}

#
# Converts local md file into html by GitHub
#
# ➥ curl -X POST --data '{"text": "Hello world github/linguist#1 **cool**, and #1!"}' https://api.github.com/markdown
# <p>Hello world github/linguist#1 <strong>cool</strong>, and #1!</p>'"
gh_toc_md2html() {
 local gh_file_md=1ドル
 URL=https://api.github.com/markdown/raw
 TOKEN="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)/token.txt"
 if [ -f "$TOKEN" ]; then
URL="$URL?access_token=$(cat $TOKEN)"
 fi
curl -s --user-agent "$gh_user_agent" \
 --data-binary @"$gh_file_md" -H "Content-Type:text/plain" \
 $URL
}

#
# Is passed string url
#
gh_is_url() {
 case 1ドル in
https* | http*)
 echo "yes";;
 *)
 echo "no";;
 esac
}

#
# TOC generator
#
gh_toc(){
 local gh_src=1ドル
 local gh_src_copy=1ドル
 local gh_ttl_docs=2ドル

 if [ "$gh_src" = "" ]; then
echo "Please, enter URL or local path for a README.md"
 exit 1
 fi


 # Show "TOC" string only if working with one document
 if [ "$gh_ttl_docs" = "1" ]; then

echo "Table of Contents"
 echo "================="
 echo ""
 gh_src_copy=""

 fi

 if [ "$(gh_is_url "$gh_src")" == "yes" ]; then
gh_toc_load "$gh_src" | gh_toc_grab "$gh_src_copy"
 else
gh_toc_md2html "$gh_src" | gh_toc_grab "$gh_src_copy"
 fi
}

#
# Grabber of the TOC from rendered html
#
# 1ドル — a source url of document.
# It's need if TOC is generated for multiple documents.
#
gh_toc_grab() {
	# if closed <h[1-6]> is on the new line, then move it on the prev line
	# for example:
	# 	was: The command <code>foo1</code>
	# 		 </h1>
	# 	became: The command <code>foo1</code></h1>
 sed -e ':a' -e 'N' -e '$!ba' -e 's/\n<\/h/<\/h/g' |
 # find strings that corresponds to template
 grep -E -o '<a\s*id="user-content-[^"]*".*</h[1-6]' |
 # remove code tags
 sed 's/<code>//' | sed 's/<\/code>//' |
 # now all rows are like:
 # <a id="user-content-..." href="..."><span ...></span></a> ... </h1
 # format result line
 # * 0ドル — whole string
 echo -e "$(awk -v "gh_url=1ドル" '{
 print sprintf("%*s", substr(0,ドル length(0ドル), 1)*3, " ") "* [" substr(0,ドル match(0,ドル /a>.*<\/h/)+2, RLENGTH-5)"](" gh_url substr(0,ドル match(0,ドル "href=\"[^\"]+?\" ")+6, RLENGTH-8) ")"}' | sed 'y/+/ /; s/%/\\x/g')"
}

#
# Returns filename only from full path or url
#
gh_toc_get_filename() {
 echo "${1##*/}"
}

#
# Options hendlers
#
gh_toc_app() {
 local app_name="gh-md-toc"

 if [ "1ドル" = '--help' ] || [ $# -eq 0 ] ; then
echo "GitHub TOC generator ($app_name): $gh_toc_version"
 echo ""
 echo "Usage:"
 echo " $app_name src [src] Create TOC for a README file (url or local path)"
 echo " $app_name - Create TOC for markdown from STDIN"
 echo " $app_name --help Show help"
 echo " $app_name --version Show version"
 return
 fi

 if [ "1ドル" = '--version' ]; then
echo "$gh_toc_version"
 return
 fi

 if [ "1ドル" = "-" ]; then
 if [ -z "$TMPDIR" ]; then
TMPDIR="/tmp"
 elif [ -n "$TMPDIR" -a ! -d "$TMPDIR" ]; then
mkdir -p "$TMPDIR"
 fi
local gh_tmp_md
 gh_tmp_md=$(mktemp $TMPDIR/tmp.XXXXXX)
 while read input; do
echo "$input" >> "$gh_tmp_md"
 done
gh_toc_md2html "$gh_tmp_md" | gh_toc_grab ""
 return
 fi

 for md in "$@"
 do
echo ""
 gh_toc "$md" "$#"
 done

echo ""
 echo "Created by [gh-md-toc](https://github.com/ekalinin/github-markdown-toc)"
}

#
# Entry point
#
gh_toc_app "$@"