#include "../../plugins/Pornhub.hpp"
#include "../../include/StringUtils.hpp"
#include "../../include/NetUtils.hpp"
extern "C" {
#include <HtmlParser.h>
}
#include <string.h>

namespace QuickMedia {
    static bool begins_with(const char *str, const char *begin_with) {
        return strncmp(str, begin_with, strlen(begin_with)) == 0;
    }

    // TODO: Optimize by using HtmlStringView instead of std::string
    struct HtmlElement {
        std::string tag_name;
        std::map<std::string, std::string> attributes;
        std::vector<HtmlElement*> children;
        HtmlElement *parent = nullptr; // ref
    };

    static void html_cleanup(HtmlElement *html_element_root) {
        for(HtmlElement *child_html_element : html_element_root->children) {
            html_cleanup(child_html_element);
        }
        delete html_element_root;
    }

    static const std::string& html_get_attribute_or(HtmlElement *html_element, const std::string &attr_key, const std::string &default_value) {
        auto it = html_element->attributes.find(attr_key);
        if(it != html_element->attributes.end())
            return it->second;
        else
            return default_value;
    }

    struct HtmlParseUserdata {
        HtmlElement *current_html_element;
    };

    static void html_page_callback(HtmlParser *html_parser, HtmlParseType parse_type, void *userdata) {
        HtmlParseUserdata *parse_userdata = (HtmlParseUserdata*)userdata;
        if(parse_type == HTML_PARSE_TAG_START) {
            auto new_html_element = new HtmlElement();
            new_html_element->tag_name.assign(html_parser->tag_name.data, html_parser->tag_name.size);
            new_html_element->parent = parse_userdata->current_html_element;

            parse_userdata->current_html_element->children.push_back(new_html_element);
            parse_userdata->current_html_element = new_html_element;
        } else if(parse_type == HTML_PARSE_TAG_END) {
            if(parse_userdata->current_html_element->parent)
                parse_userdata->current_html_element = parse_userdata->current_html_element->parent;
        } else if(parse_type == HTML_PARSE_ATTRIBUTE) {
            std::string attr_key(html_parser->attribute_key.data, html_parser->attribute_key.size);
            std::string attr_value(html_parser->attribute_value.data, html_parser->attribute_value.size);
            parse_userdata->current_html_element->attributes.insert(std::make_pair(std::move(attr_key), std::move(attr_value)));
        }
    }

    static HtmlElement* html_parse(char *source, size_t size) {
        HtmlElement *html_element_root = new HtmlElement();
        HtmlParseUserdata parse_userdata;
        parse_userdata.current_html_element = html_element_root;
        HtmlParser html_parser;
        html_parser_init(&html_parser, source, size, html_page_callback, &parse_userdata);
        html_parser_parse(&html_parser);
        html_parser_deinit(&html_parser);
        return html_element_root;
    }

    using HtmlFindTagsCallback = std::function<void(HtmlElement *html_element)>;
    static void html_find_tags_with_class(HtmlElement *html_element, const std::string &tag_name, const std::string &class_value, const HtmlFindTagsCallback &callback) {
        if(html_element->tag_name == tag_name) {
            if(html_get_attribute_or(html_element, "class", "") == class_value)
                callback(html_element);
        }
        for(HtmlElement *child_html_element : html_element->children) {
            html_find_tags_with_class(child_html_element, tag_name, class_value, callback);
        }
    }

    static void html_find_tags(HtmlElement *html_element, const std::string &tag_name, const HtmlFindTagsCallback &callback) {
        if(html_element->tag_name == tag_name)
            callback(html_element);
        for(HtmlElement *child_html_element : html_element->children) {
            html_find_tags(child_html_element, tag_name, callback);
        }
    }

    static SearchResult get_videos_in_page(const std::string &url, bool use_tor, BodyItems &result_items) {
        std::string website_data;
        if(download_to_string(url, website_data, {}, use_tor) != DownloadResult::OK)
            return SearchResult::NET_ERR;

        HtmlElement *html_root = html_parse(website_data.data(), website_data.size());
        html_find_tags_with_class(html_root, "div", "phimage", [&result_items](HtmlElement *html_element) {
            auto it = html_element->attributes.find("data-entrycode");
            if(it == html_element->attributes.end() || it->second != "VidPg-premVid-videoPage") {
                html_find_tags(html_element, "a", [&result_items](HtmlElement *html_element) {
                    const std::string &href = html_get_attribute_or(html_element, "href", "");
                    const std::string &title = html_get_attribute_or(html_element, "title", "");
                    if(!href.empty() && !title.empty() && begins_with(href.c_str(), "/view_video.php?viewkey")) {
                        std::string title_fixed = strip(title);
                        html_unescape_sequences(title_fixed);
                        auto item = BodyItem::create(std::move(title_fixed));
                        item->url = std::string("https://www.pornhub.com") + href;
                        item->thumbnail_size = sf::Vector2i(192, 108);
                        result_items.push_back(std::move(item));

                        html_find_tags(html_element, "img", [&result_items](HtmlElement *html_element) {
                            const std::string &src = html_get_attribute_or(html_element, "data-src", "");
                            if(src.find("phncdn.com/videos") != std::string::npos)
                                result_items.back()->thumbnail_url = src;
                        });
                    }
                });
            }
        });
        html_cleanup(html_root);

        // Attempt to skip promoted videos (that are not related to the search term)
        if(result_items.size() >= 4)
            result_items.erase(result_items.begin(), result_items.begin() + 4);

        return SearchResult::OK;
    }

    SearchResult PornhubSearchPage::search(const std::string &str, BodyItems &result_items) {
        std::string url = "https://www.pornhub.com/video/search?search=";
        url += url_param_encode(str);
        return get_videos_in_page(url, is_tor_enabled(), result_items);
    }

    PluginResult PornhubSearchPage::submit(const std::string &title, const std::string &url, std::vector<Tab> &result_tabs) {
        (void)title;
        (void)url;
        result_tabs.push_back(Tab{create_body(), std::make_unique<PornhubVideoPage>(program), nullptr});
        return PluginResult::OK;
    }

    BodyItems PornhubVideoPage::get_related_media(const std::string &url) {
        BodyItems result_items;
        get_videos_in_page(url, is_tor_enabled(), result_items);
        return result_items;
    }
}