#!/usr/bin/python

#TODO : gitignore
#unlink => try ... except -> no exception on filenotfound
#filename[4:] not good

import sys
import shutil
import os
import datetime
import subprocess

def isset(variable):
	return variable in locals() or variable in globals()

def list_directory(path): 
    fichier=[] 
    for root, dirs, files in os.walk(path): 
        for i in files: 
            fichier.append(os.path.join(root, i)) 
    return fichier

def get_tags(fh):
	line = fh.readline()
	while "@tags=" not in line:
		line = fh.readline()
	if "@tags" not in line:
		return []
		
	line = line.strip() #Delete \n at the end of the line
	tag_pos = line.find("@tags=")
	tags = line[tag_pos+6:].split(",")
	return tags


#Find the changes to be committed
try:
	#TODO : Check this command
	changes = subprocess.check_output(["git", "diff", "--cached", "--name-status"], universal_newlines=True)
except:
	sys.stderr.write("[ERROR] An error occured when running git diff")
	sys.exit(1)

#Fill lists for modified, deleted and added files
modified_files = []
deleted_files = []
added_files = []

changes = changes.strip().split("\n")

for changed_file in changes:
	if changed_file[0] == "A":
		added_files.append(changed_file[changed_file.index("\t")+1:])
	elif changed_file[0] == "M":
		modified_files.append(changed_file[changed_file.index("\t")+1:])
	elif changed_file[0] == "D":
		deleted_files.append(changed_file[changed_file.index("\t")+1:])
	else:
		sys.stderr.write("[ERROR] An error occured when running git diff")
		sys.exit(1)

print("[INFO] Added files : "+", ".join(added_files))
print("[INFO] Modified files : "+", ".join(modified_files))
print("[INFO] Deleted filed : "+", ".join(deleted_files))

print("[INFO] Updating tags for added and modified files")
for filename in added_files:
	with open(filename, 'r') as fh:
		tags = get_tags(fh)
		if len(tags) > 0:
			for tag in tags:
				try:
					with open("gen/tags/"+tag+".tmp", 'a+') as tag_file:
						tag_file.seek(0)
						if filename[4:] not in tag_file.read():
							tag_file.write(filename[4:]+"\n") 
						print("[INFO] (TAGS) Found tag "+tag+" for article "+filename[4:])		
						pass
				except IOError:
					sys.stderr.write("[ERROR] (TAGS) New tag found but error occured in article "+filename[4:]+": "+tag)
		else:
			sys.stderr.write("[ERROR] (TAGS) In added article "+filename[4:]+" : No tags found !")

for filename in modified_files:
	with open(filename, 'r') as fh:
		tags = get_tags(fh)
		if(len(tags)) > 0:
			for tag in list_directory("gen/tags/"):
				try:
					with open(tag, 'r+') as tag_file:
						if tag[tag.index("tags/") + 5:tag.index(".tmp")] in tags and filename[4:] not in tag_file.read():
								tag_file.seek(0, 2) #Append to end of file
								tag_file.write(filename[4:]+"\n")
								print("[INFO] (TAGS) Found new tag "+tag[:tag.index(".tmp")+" for modified article "+filename[4:])
						if tag[tag.index("tags/") + 5:tag_index(".tmp")] not in tags and filename[4:] in tag_file.read():
								old_tag_file_content = tag_file.read()
								tag_file.truncate()
								tag_file.write(old_tag_file_content.replace(filename"\n", ""))
								print("[INFO] (TAGS) Deleted tag "+tag[:tag.index(".tmp")+" in modified article "+filename[4:])
				except IOError:
					sys.stderr.write("[ERROR] (TAGS) An error occured when parsing tags of article "+filename[4:])
		else:
			sys.stderr.write("[ERROR] (TAGS) In modified article "+filename[4:]+" : No tags found !")


#Delete tags for deleted files and delete all generated files
for filename in deleted_files:
	with open(filename, 'r') as fh:
		tags = get_tags(fh)
		if len(tags) > 0:
			for tag in tags:
				try:
					with open("gen/tags/"+tag+".tmp", 'r+') as tag_file:
						old_tag_file_content = tag_file.read()
						tag_file.truncate()
						#Delete file in tag
						tag_file.write(old_tag_file_content).replace(filename+"\n", ""))
				except IOError:
					sys.stderr.write("[ERROR] An error occured while deleting article "+filename[4:]+" from tags files")
		else:
			sys.stderr.write("[ERROR] (TAGS) In deleted article "+filename[4:]+" : No tags found !")
	#Delete generated files
	os.unlink("gen/"+filename[4:-5]+".gen")
	os.unlink("blog/"+filename)
	print("[INFO] Deleted article "+filename[4:]+" in both gen and blog directories")

#Delete empty tags files 
for tag in list_directory("gen/tags"):
	with open(tag, 'r') as tag_file:
		content = tag_file.read().strip()
	if content == '':
		os.unlink(tag)
		#TODO : Delete tag in blog directory too
		print("[INFO] (TAGS) No more article with tag "+tag[]+", deleting it.")

#TODO ||
#	  \/

#(Re)Generate HTML files
for filename in added_files:
	with open(filename, 'r') as fh:
		#Generate HTML for the updated articles
		for line in fh.readlines():
			if "@title=" in line:
				line = line.strip()
				title_pos = line.find("@title=")
				title = line[title_pos+7:]
				continue
			
			if "@date=" in line:
				line = line.strip()
				date_pos = line.find("@date=")
				date = line[date_pos+6:]
				continue
			
			if isset("date") and isset("title"):
				break

		fh.seek(0)
		article = fh.read()

		try:
			with open("gen/"+filename[4:-5]+".gen", 'w') as article_file:
				article_file.write("<article><nav class=\"aside_article\"></nav><div class=\"article\"><h1>"+title+"</h1>"+article+"<p class=\"date\">"+date+"</p></div>\n")
				print("[GEN ARTICLES] Article "+filename[4:]+" generated")
		except:
			print("[GEN ARTICLES ERROR] An error occurred while generating article "+filename[4:])

#Generate headers file (except title)
with open("raw/header.html") as header_fh:
	#Tags
	tags = os.listdir("gen/tags")
	header = header_fh.read()
	tags_header = "<ul>"
	for tag in tags:
		tags_header += "<li><a href=\"tags/"+tag[:-4]+".html\">"+tag[:-4]+"</a></li>"
	tags_header += "</ul>"
	header = header.replace("@categories", tags_header, 1)

	#Articles
	latest_articles = list_directory("gen")
	latest_articles = [i for i in latest_articles if i[4:8].isdigit()]
	latest_articles.sort()
	articles_header = "<ul>"
	for article in latest_articles[0:5]:
		with open(article, 'r') as fh:
			line = fh.readline()
			while "@title" not in line:
				line = fh.readline()
			line = line.strip()
			title_pos = line.find("@title=")
			title = line[title_pos+7:]

			articles_header += "<li><a href=\""+article[4:-4]+".html\">"+title+"</a></li>"
	articles_header += "</ul>"
	header = header.replace("@articles", articles_header, 1)

	with open("gen/header.gen", "w") as header_gen_fh:
		header_gen_fh.write(header)
		print("[GEN HEADER] Header has been generated successfully")

#Generate footer file
shutil.copy("raw/footer.html", "gen/footer.gen")
print("[GEN FOOTER] Footer has been generated successfully")

#Regenerate index file
#* First, get last 25 articles
last_25_articles = latest_articles[0:25]
#* Then generate effectively the index file
with open("blog/index.html", "w") as index_fh:
	with open("gen/header.gen", "r") as header_gen_fh:
		index = header_gen_fh.read()
	for article in last_25_articles:
		with open("gen/"+article, "r") as article_fh:
			index += article_fh.read()
	with open("gen/footer.gen") as footer_gen_fh:
		index += footer_gen_fh.read()
	index_fh.write(index)

#Regenerate tags pages
for tag in listdir("gen/tags"):
	if not isdir(tag):
		with open(tag) as tag_fh:
			with open("gen/header.gen") as header_handler:
				tag_content = header_handler.read()
				tag_content.replace("<title>@titre</title", "<title>"+tag+"</title>")
			tag_fh_lines = tag_fh.readlines()
			for line in tag_fh_lines:
				line = line.replace(".html", ".gen")
				with open("gen/"+line) as article_handler:	
					tag_content += "<section>"+article_handler.read()+"</section>\n"
			with open("gen/footer.gen") as footer_handler:
				tag_content += footer_handler.read()
			tag_fh.write(tag_content)

#Finish articles pages generation
for filename in sys.argv[1]:
	with open("blog/"+filename, "w") as article_fh:
		with open("gen/header.gen", "r") as header_gen_fh:
			article = header_gen_fh.read()
		with open("gen/"+filename, "r") as article_gen_fh:
			article += article_gen_fh.read()
		with open("gen/footer.gen", "r") as footer_gen_fh:
			article += footer_gen_fh.read()
		article_fh.write(article)


#Generate RSS