#!/usr/bin/env python3

from pygments import highlight
from pygments.lexers import get_lexer_by_name
from pygments.formatters import HtmlFormatter
from urllib.parse import urlparse

import urllib.parse
import lxml.html
import argparse
import database
import mistune
import houdini
import jinja2
import parser
import shutil
import sys

ENV = jinja2.Environment(loader=jinja2.FileSystemLoader('templates'))

class MyRenderer(mistune.HTMLRenderer):
    def block_code(self, code, info=None):
        if not info:
            return '\n<pre><code>{}</code></pre>\n'.format(houdini.escape_html(code.strip()))
        lexer = get_lexer_by_name(info, stripall=True)
        formatter = HtmlFormatter()
        return highlight(code, lexer, formatter)

    def block_quote(self, content):
        content = content[3:-5]
        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>\n" % (
            level, hash_, text, hash_, level
        )

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

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 = MyRenderer(),
        plugins = ["strikethrough", "table", "url", "task_lists", "def_list"]
    )
    html = md(unformatted)
    if html == "":
        return "", ""

    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((
            urllib.parse.unquote_plus(node.attrib["id"]),
            level,
            "#%s" % node.attrib["id"])
        )

    headers = [(i[0], i[1] - thesmallestlevel, i[2]) for i in headers]
    md_template = jinja2.Template("""
        {% for text, depth, link in contents %}
            {{ "    " * depth }} - [{{ text }}]({{ link }})
        {% endfor %}
            """)

    return mistune.html(md_template.render(contents = headers))

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")
    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, echo_parser, update_parser]:
        s.add_argument(
            "-m", "--markdown",
            help = "Path to a markdown file",
            type = str,
            required = True
        )

    for s in [save_parser]:
        s.add_argument(
            "-t", "--title",
            help = "Article title",
            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())

    try:
        verb = sys.argv[1]
    except IndexError:
        print("Error! No verb specified. Nothing to do... Exiting...")
        exit()

    if verb in ["save", "export", "update", "list"]:
        with database.Database() as db:
            match verb:
                case "save":
                    with open(args["markdown"], "r") as f:
                        db.add_thought(args["title"], f.read())
                    print("Added thought.")
                case "export":
                    with open(args["out"], "w") as f:
                        f.writelines(db.get_thought(args["id"]))
                    print(f"Written to {args["out"]}")
                case "update":
                    with open(args["markdown"], "r") as f:
                        db.update_thought_markdown(args["id"], f.read())
                    print("Updated thought.")
                case "list":
                    for id_, title, datetime in db.get_all_thoughts():
                        print(f"{id_}, {title}, {datetime}")
                case _:
                    print("Error! Unknown verb... Exiting...")
                    exit()
    elif verb == "echo":
        print(parse_file(args["markdown"]))

if __name__ == '__main__':
    main()