#!/usr/bin/env python3

from urllib.parse import urlparse
from pygments import highlight
from pygments.formatters import HtmlFormatter, ClassNotFound
from pygments.lexers import get_lexer_by_name
import urllib.parse
import webbrowser
import lxml.etree
import lxml.html
import database
import argparse
import getpass
import houdini
import mistune
import jinja2
import app
import sys
import re
import os

class EdawebRenderer(mistune.HTMLRenderer):
    def blockcode(self, text, lang):
        try:
            lexer = get_lexer_by_name(lang, stripall=True)
        except ClassNotFound:
            lexer = None

        if lexer:
            formatter = HtmlFormatter()
            return highlight(text, lexer, formatter)
        # default
        return '\n<pre><code>{}</code></pre>\n'.format(houdini.escape_html(text.strip()))

    def block_quote(self, content):
        content = content[3:-5] # idk why this is required...
        out = '\n<blockquote>'
        for line in houdini.escape_html(content.strip()).split("\n"):
            out += '\n<span class="quote">{}</span><br>'.format(line)
        return out + '\n</blockquote>'

    def image(self, link, text, title):
        return "<a href='%s' target='_blank'><img alt='%s' src='%s'></a>" % (
            urlparse(link)._replace(query='').geturl(), text, link
        )

    def heading(self, text, level):
        hash_ = urllib.parse.quote_plus(text)
        return "<h%d id='%s'>%s <a class='header_linker' href='#%s'>[#]</a></h%d>" % (
            level, hash_, text, hash_, level
        )

def get_thought_from_id(db, id_):
    category_name, title, dt, markdown = db.get_thought(id_)
    html, headers = parse_text(markdown)
    return category_name, title, dt, html, headers

def parse_file(path):
    with open(path, "r") as f:
        unformatted = f.read()

    return parse_text(unformatted)[0]    

def parse_text(unformatted):
    md = mistune.create_markdown(
        renderer = EdawebRenderer(), 
        plugins = ["strikethrough", "table", "url", "task_lists"]
    )
    html = md(unformatted)

    return html, get_headers(html)

def get_headers(html):
    root = lxml.html.fromstring(html)

    headers = []
    thesmallestlevel = 7
    for node in root.xpath('//h1|//h2|//h3|//h4|//h5//h6'):
        level = int(node.tag[-1])
        if level < thesmallestlevel:
            thesmallestlevel = level
        headers.append((
            # lxml.etree.tostring(node),
            # "<p>%s</p>" % urllib.parse.unquote_plus(node.attrib["id"]),     # possibly insecure?
            urllib.parse.unquote_plus(node.attrib["id"]),
            level,                                              #   -horrible hack
            "#%s" % node.attrib["id"])
        )
    
    headers = [(i[0], i[1] - thesmallestlevel, i[2]) for i in headers]
    # print(headers)
    # there is a bug here-
    # it must start with the largest header and only go up and down in increments of one
    #       TODO: fix it!
    md_template = jinja2.Template("""
{% for text, depth, link in contents %}
{{ "    " * depth }} - [{{ text }}]({{ link }})
{% endfor %}
    """)
    
    return mistune.html(md_template.render(contents = headers))

def preview_markdown(path, title, category):
    def startBrowser():
        # webbrowser.get("firefox").open("http://localhost:5000/preview")
        webbrowser.open("http://localhost:5000/preview")
        del os.environ["PREVIEW"]
        del os.environ["PREVIEW_TITLE"]
        del os.environ["CATEGORY"]

    os.environ["PREVIEW"] = parse_file(path)
    os.environ["PREVIEW_TITLE"] = title
    os.environ["CATEGORY"] = category

    import threading
    threading.Timer(1.25, startBrowser ).start()
    
    app.app.run(host = "0.0.0.0", debug = True)

def main():
    p = argparse.ArgumentParser()
    subparse = p.add_subparsers(help = "sub-command help")
    save_parser = subparse.add_parser("save", help = "Add a markdown file to the database")
    preview_parser = subparse.add_parser("preview", help = "Preview a markdown render")
    echo_parser = subparse.add_parser("echo", help = "Print markdown render to stdout")
    update_parser = subparse.add_parser("update", help = "Replace a markdown file")
    export_parser = subparse.add_parser("export", help = "Export a database markdown file to disk")
    list_parser = subparse.add_parser("list", help = "List all the markdowns in the database")

    for s in [save_parser, preview_parser, echo_parser, update_parser]:
        s.add_argument(
            "-m", "--markdown",
            help = "Path to a markdown file",
            type = str,
            required = True
        )
    
    for s in [save_parser, preview_parser]:
        s.add_argument(
            "-t", "--title",
            help = "Article title",
            type = str,
            required = True
        )
        s.add_argument(
            "-c", "--category",
            help = "Article category",
            type = str,
            required = True
        )

    for s in [save_parser, update_parser, export_parser, list_parser]:
        s.add_argument(
            "-u", "--username",
            help = "Username to use for the database",
            type = str,
            required = True
        )

    for s in [export_parser, update_parser]:
        s.add_argument(
            "-i", "--id",
            help = "Article's id",
            type = int,
            required = True
        )

    export_parser.add_argument(
        "-o", "--out",
        help = "Path to write the markdown file to",
        type = str,
        required = True
    )

    args = vars(p.parse_args())

    if "username" in args.keys():
        args["password"] = getpass.getpass("Enter password for %s@%s: " % (args["username"], app.CONFIG["mysql"]["host"]))

    try:
        verb = sys.argv[1]
    except IndexError:
        print("No verb specified... Nothing to do... Exiting...")
        exit()
    
    if verb in ["save", "export", "update", "list"]:
        with database.Database(
            safeLogin = False,
            user = args["username"],
            passwd = args["password"]
        ) as db:
            if verb == "save":
                if db.add_category(args["category"]):
                    print("Added category...")
                with open(args["markdown"], "r") as f:
                    db.add_thought(args["category"], args["title"], f.read())
                print("Added thought...")

            elif verb == "export":
                with open(args["out"], "w") as f:
                    f.writelines(db.get_thought(args["id"])[-1])
                print("Written to %s" % args["out"])

            elif verb == "update":
                with open(args["markdown"], "r") as f:
                    db.update_thought_markdown(args["id"], f.read())

            elif verb == "list":
                for id_, title, dt, category_name in db.get_all_thoughts():
                    print("%d\t%s\t%s\t%s" % (id_, title, dt, category_name))

    if verb == "preview":
        preview_markdown(args["markdown"], args["title"], args["category"])

    elif verb == "echo":
        print(parse_file(args["markdown"]))

if __name__ == "__main__":
    main()