from bottle import route, run, template, request
from bs4 import BeautifulSoup, Tag
import time
import urllib.request
import urllib.parse

targets = {
    "html2_0": {
        "elements": [
            "a", "address", "b", "base", "blockquote", "body", "br", "cite", "code", "dd", "dir", "dl", "dt", "em", "form", "h1", "h2", "h3", "h4", "h5", "h6", "head", "hr", "html", "i", "img", "input", "isindex", "kbd", "li", "listing", "menu", "meta", "nextid", "ol", "option", "p", "plaintext", "pre", "samp", "select", "strong", "textarea", "title", "tt", "ul", "var", "xmp"
            # "link"
        ],
        "flatten_elements": [
            "div", "center", "article", "main", "footer", "header", "section"
        ],
        "allowed_attributes": {
            "a": ["href", "methods", "rel", "rev", "urn" ], # name, title
            "base": ["href"],
            "dir": ["compact"],
            "dl": ["compact"],
            "form": ["action", "enctype", "method"],
            "html": ["version"],
            "img": ["align", "alt", "ismap", "src"],
            "input": ["align", "checked", "maxlength", "name", "size", "src", "type", "value"],
            "link": ["href", "methods", "rel", "rev", "title", "urn"],
            "menu": ["compact"],
            "meta": ["content", "http-equiv", "name"],
            "nextid": ["n"],
            "ol": ["compact"],
            "option": ["selected", "value"],
            "pre": ["width"],
            "select": ["multiple", "name", "size"],
            "textarea": ["cols", "name", "rows"],
            "ul": ["compact"]
        }
    }
}

def parse_for_target(src, target, targets_dict):
    current_target = targets_dict[target]
    target_tags = current_target["elements"]
    allowed_attrs = current_target["allowed_attributes"]
    flatten_elements = current_target["flatten_elements"]

    html = BeautifulSoup(src, "html.parser")
    body = html.find("body")

    final_html = ""

    # Unwrap the content from certain elements like div, so that we dont get really big nests of div's and stuff
    for x in body.find_all(flatten_elements, recursive=True):
        x.unwrap()

    for x in body.find_all(recursive=True):
        # Remove the element if its not in our allowlist
        if (x.name not in target_tags):
            x.extract()
            continue
        # Strip all attributes aside from the ones we added into the allowlist
        new_attrs = {}
        for key, value in list(x.attrs.items()):
            if (x.name in allowed_attrs) and (key in allowed_attrs[x.name]):
                new_attrs[key] = value
        x.attrs = new_attrs
        # Remove elements that have no content and no attributes
        if (len(x.get_text(strip=True)) == 0 and x.attrs == {}):
            x.extract()
            continue
        # Strip the text content of all elements for better looking pages in the absence of css
        x.string = x.text.strip("\n\r ")

    for t in body:
        # Add the element to the final html string, but before that, strip it of any leading whitespace
        s = str(t)
        st = s.strip()
        if s != st and st == "":
            st = " "
        final_html += st

    return final_html


@route('/page/html20/view')
def index():
    print("* process page begin - target: html20(html2_0); via: http")

    print("  --> fetch page begin")
    fetch_start_time = time.time()
    chosen_page_content = urllib.request.urlopen(request.query.url)
    fetch_end_time = time.time()
    fetch_time_taken = round(fetch_end_time - fetch_start_time, 3)
    print(f"  --> fetch page finished - time_taken: { fetch_time_taken }s")

    print("  --> render page begin")
    render_page_start_time = time.time()
    parsed_page = parse_for_target(chosen_page_content, "html2_0", targets)
    render_page_end_time = time.time()
    render_page_time_taken = round(render_page_end_time - render_page_start_time, 3)
    print(f"  --> render page finished - time_taken: { render_page_time_taken }s")

    total_time_taken = round(render_page_time_taken + fetch_time_taken, 3)

    print(f"* process page finished - total_time_taken: { total_time_taken }s")

    return template("templates/page.html", {
        "page_content": parsed_page,
        "page_title": "viewing page: " + request.query.url
    })

run(host='localhost', port=8080)