'''Tools for GAIA question answering agent.'''

import bleach
import requests
from bleach.css_sanitizer import CSSSanitizer
from bs4 import BeautifulSoup
from smolagents import tool
from googlesearch import search

@tool
def google_search(query: str) -> dict:
    """
    Perform a Google search and return the top 10 results.
    
    Args:
        query (str): The search query.
        
    Returns:
        dict: A dictionary containing the search results in the following format.
        {0: {'title': str, 'url': str, 'description': str}, ...}
    """

    # Run the query
    results = list(search(query, num_results=5, advanced=True))

    # Parse and format the results
    parsed_results = {}

    for i, result in enumerate(results):

        parsed_results[i] = {
            'title': result.title,
            'url': result.url,
            'description': result.description
        }

    return parsed_results


@tool
def wikipedia_search(query: str) -> dict:
    """
    Perform a search for wikipedia pages and return the top 5 results.
    
    Args:
        query (str): The search query.
        
    Returns:
        dict: A dictionary containing the search results in the following format.
        {0: {'title': str, 'description': str}, ...}
    """

    language_code = 'en'
    number_of_results = 5
    headers = {
        'User-Agent': 'HuggingFace Agents course final project (https://github.com/gperdrizet/unit-four-final-project)'
    }

    base_url = 'https://api.wikimedia.org/core/v1/wikipedia/'
    endpoint = '/search/page'
    url = base_url + language_code + endpoint
    parameters = {'q': query, 'limit': number_of_results}
    response = requests.get(url, headers=headers, params=parameters, timeout=15)

    if response.status_code == 200:
        results = response.json().get('pages', [])
        parsed_results = {}

    else:
        return f"Error: Unable to retrieve page. Status code {response.status_code}"

    for i, result in enumerate(results):

        parsed_results[i] = {
            'title': result.get('title', None),
            'description': result.get('description', None)
        }

    return parsed_results


@tool
def get_wikipedia_page(query: str) -> str:
    """
    Get the content of a Wikipedia page as HTML.

    Args:
        query (str): The title of the Wikipedia page.
        
    Returns:
        str: The HTML content of the Wikipedia page.
    """

    fetcher = WikipediaFetcher()
    html_result = fetcher.fetch(query.replace(' ', '_'))

    content = html_result['content']
    content = content.split('<div class="mw-heading mw-heading2"><h2 id="Further_reading">Further reading</h2></div>')[0]
    content = content.split('<div class="mw-heading mw-heading2"><h2 id="References">References</h2></div>')[0]

    return content


class WikipediaFetcher:
    """Gets and cleans up Wikipedia pages."""

    def fetch(self, page_name):
        """
        Passed a Wikipedia page's URL fragment, like
        'Edward_Montagu,_1st_Earl_of_Sandwich', this will fetch the page's
        main contents, tidy the HTML, strip out any elements we don't want
        and return the final HTML string.

        Returns a dict with two elements:
            'success' is either True or, if we couldn't fetch the page, False.
            'content' is the HTML if success==True, or else an error message.
        """
        result = self._get_html(page_name)

        if result["success"]:
            result["content"] = self._tidy_html(result["content"])

        return result


    def _get_html(self, page_name):
        """
        Passed the name of a Wikipedia page (eg, 'Samuel_Pepys'), it fetches
        the HTML content (not the entire HTML page) and returns it.

        Returns a dict with two elements:
            'success' is either True or, if we couldn't fetch the page, False.
            'content' is the HTML if success==True, or else an error message.
        """
        error_message = ""

        url = f"https://en.wikipedia.org/wiki/{page_name}"

        try:
            response = requests.get(url, params={"action": "render"}, timeout=5)
        except requests.exceptions.ConnectionError:
            error_message = "Can't connect to domain."
        except requests.exceptions.Timeout:
            error_message = "Connection timed out."
        except requests.exceptions.TooManyRedirects:
            error_message = "Too many redirects."

        try:
            response.raise_for_status()
        except requests.exceptions.HTTPError:
            # 4xx or 5xx errors:
            error_message = f"HTTP Error: {response.status_code}"
        except NameError:
            if error_message == "":
                error_message = "Something unusual went wrong."

        if error_message:
            return {"success": False, "content": error_message}
        else:
            return {"success": True, "content": response.text}


    def _tidy_html(self, html):
        """
        Passed the raw Wikipedia HTML, this returns valid HTML, with all
        disallowed elements stripped out.
        """
        html = self._bleach_html(html)
        html = self._strip_html(html)
        return html


    def _bleach_html(self, html):
        """
        Ensures we have valid HTML; no unclosed or mis-nested tags.
        Removes any tags and attributes we don't want to let through.
        Doesn't remove the contents of any disallowed tags.

        Pass it an HTML string, it'll return the bleached HTML string.
        """

        # Pretty much most elements, but no forms or audio/video.
        allowed_tags = {
            "a",
            "abbr",
            "acronym",
            "address",
            "area",
            "article",
            "b",
            "blockquote",
            "br",
            "caption",
            "cite",
            "code",
            "col",
            "colgroup",
            "dd",
            "del",
            "dfn",
            "div",
            "dl",
            "dt",
            "em",
            "figcaption",
            "figure",
            "footer",
            "h1",
            "h2",
            "h3",
            "h4",
            "h5",
            "h6",
            "header",
            "hgroup",
            "hr",
            "i",
            "img",
            "ins",
            "kbd",
            "li",
            "map",
            "nav",
            "ol",
            "p",
            "pre",
            "q",
            "s",
            "samp",
            "section",
            "small",
            "span",
            "strong",
            "sub",
            "sup",
            "table",
            "tbody",
            "td",
            "tfoot",
            "th",
            "thead",
            "time",
            "tr",
            "ul",
            "var",
            # We allow script and style here, so we can close/un-mis-nest
            # its tags, but then it's removed completely in _strip_html():
            "script",
            "style",
        }

        # These attributes will not be removed from any of the allowed tags.
        allowed_attributes = {
            "*": ["class", "id"],
            "a": ["href", "title"],
            "abbr": ["title"],
            "acronym": ["title"],
            "img": ["alt", "src", "srcset"],
            # Ugh. Don't know why this page doesn't use .tright like others
            # http://127.0.0.1:8000/encyclopedia/5040/
            "table": ["align"],
            "td": ["colspan", "rowspan", "style"],
            "th": ["colspan", "rowspan", "scope"],
        }

        # These CSS properties are allowed within style attributes
        # Added for the family tree on /encyclopedia/5825/
        # Hopefully doesn't make anything else too hideous.
        allowed_css_properties = [
            "background",
            "border",
            "border-bottom",
            "border-collapse",
            "border-left",
            "border-radius",
            "border-right",
            "border-spacing",
            "border-top",
            "height",
            "padding",
            "text-align",
            "width",
        ]

        css_sanitizer = CSSSanitizer(allowed_css_properties=allowed_css_properties)

        a = bleach.clean(
            html,
            tags=allowed_tags,
            attributes=allowed_attributes,
            css_sanitizer=css_sanitizer,
            strip=True,
        )

        return a


    def _strip_html(self, html):
        """
        Takes out any tags, and their contents, that we don't want at all.
        And adds custom classes to existing tags (so we can apply CSS styles
        without having to multiply our CSS).

        Pass it an HTML string, it returns the stripped HTML string.
        """

        # CSS selectors. Strip these and their contents.
        selectors = [
            "div.hatnote",
            "div.navbar.mini",  # Will also match div.mini.navbar
            # Bottom of https://en.wikipedia.org/wiki/Charles_II_of_England :
            "div.topicon",
            "a.mw-headline-anchor",
            "script",
            "style",
        ]

        # Strip any element that has one of these classes.
        classes = [
            # "This article may be expanded with text translated from..."
            # https://en.wikipedia.org/wiki/Afonso_VI_of_Portugal
            "ambox-notice",
            "magnify",
            # eg audio on https://en.wikipedia.org/wiki/Bagpipes
            "mediaContainer",
            "navbox",
            "noprint",
        ]

        # Any element has a class matching a key, it will have the classes
        # in the value added.
        add_classes = {
            # Give these tables standard Bootstrap styles.
            "infobox": ["table", "table-bordered"],
            "ambox": ["table", "table-bordered"],
            "wikitable": ["table", "table-bordered"],
        }

        soup = BeautifulSoup(html, "lxml")

        for selector in selectors:
            [tag.decompose() for tag in soup.select(selector)]

        for clss in classes:
            [tag.decompose() for tag in soup.find_all(attrs={"class": clss})]

        for clss, new_classes in add_classes.items():
            for tag in soup.find_all(attrs={"class": clss}):
                tag["class"] = tag.get("class", []) + new_classes

        # Depending on the HTML parser BeautifulSoup used, soup may have
        # surrounding <html><body></body></html> or just <body></body> tags.
        if soup.body:
            soup = soup.body
        elif soup.html:
            soup = soup.html.body

        # Put the content back into a string.
        html = "".join(str(tag) for tag in soup.contents)

        return html