#include "../../plugins/Youtube.hpp"
#include "../../include/Storage.hpp"
#include "../../include/NetUtils.hpp"
#include <string.h>
#include <unordered_set>

namespace QuickMedia {
    static std::shared_ptr<BodyItem> parse_common_video_item(const Json::Value &video_item_json, std::unordered_set<std::string> &added_videos) {
        const Json::Value &video_id_json = video_item_json["videoId"];
        if(!video_id_json.isString())
            return nullptr;

        std::string video_id_str = video_id_json.asString();
        if(added_videos.find(video_id_str) != added_videos.end())
            return nullptr;

        std::string thumbnail_url = "https://img.youtube.com/vi/" + video_id_str + "/hqdefault.jpg";

        const char *date = nullptr;
        const Json::Value &published_time_text_json = video_item_json["publishedTimeText"];
        if(published_time_text_json.isObject()) {
            const Json::Value &text_json = published_time_text_json["simpleText"];
            if(text_json.isString())
                date = text_json.asCString();
        }

        const char *length = nullptr;
        const Json::Value &length_text_json = video_item_json["lengthText"];
        if(length_text_json.isObject()) {
            const Json::Value &text_json = length_text_json["simpleText"];
            if(text_json.isString())
                length = text_json.asCString();
        }

        const char *view_count_text = nullptr;
        const Json::Value &view_count_text_json = video_item_json["viewCountText"];
        if(view_count_text_json.isObject()) {
            const Json::Value &text_json = view_count_text_json["simpleText"];
            if(text_json.isString())
                view_count_text = text_json.asCString();
        }

        const char *owner_text = nullptr;
        const Json::Value &owner_text_json = video_item_json["shortBylineText"];
        if(owner_text_json.isObject()) {
            const Json::Value &runs_json = owner_text_json["runs"];
            if(runs_json.isArray() && !runs_json.empty()) {
                const Json::Value &first_runs_json = runs_json[0];
                if(first_runs_json.isObject()) {
                    const Json::Value &text_json = first_runs_json["text"];
                    if(text_json.isString())
                        owner_text = text_json.asCString();
                }
            }
        }

        const char *title = nullptr;
        const Json::Value &title_json = video_item_json["title"];
        if(title_json.isObject()) {
            const Json::Value &simple_text_json = title_json["simpleText"];
            if(simple_text_json.isString()) {
                title = simple_text_json.asCString();
            } else {
                const Json::Value &runs_json = title_json["runs"];
                if(runs_json.isArray() && !runs_json.empty()) {
                    const Json::Value &first_runs_json = runs_json[0];
                    if(first_runs_json.isObject()) {
                        const Json::Value &text_json = first_runs_json["text"];
                        if(text_json.isString())
                            title = text_json.asCString();
                    }
                }
            }
        }

        if(!title)
            return nullptr;
        
        auto body_item = BodyItem::create(title);
        std::string desc;
        if(view_count_text)
            desc += view_count_text;
        if(date) {
            if(!desc.empty())
                desc += " • ";
            desc += date;
        }
        if(length) {
            if(!desc.empty())
                desc += '\n';
            desc += length;
        }
        if(owner_text) {
            if(!desc.empty())
                desc += '\n';
            desc += owner_text;
        }
        body_item->set_description(std::move(desc));
        body_item->url = "https://www.youtube.com/watch?v=" + video_id_str;
        body_item->thumbnail_url = std::move(thumbnail_url);
        body_item->thumbnail_size = sf::Vector2i(158, 119);
        added_videos.insert(video_id_str);
        return body_item;
    }

    static std::shared_ptr<BodyItem> parse_content_video_renderer(const Json::Value &content_item_json, std::unordered_set<std::string> &added_videos) {
        if(!content_item_json.isObject())
            return nullptr;
        
        const Json::Value &video_renderer_json = content_item_json["videoRenderer"];
        if(!video_renderer_json.isObject())
            return nullptr;

        return parse_common_video_item(video_renderer_json, added_videos);
    }

    // Returns empty string if continuation token can't be found
    static std::string item_section_renderer_get_continuation_token(const Json::Value &item_section_renderer_json) {
        const Json::Value &continuation_item_renderer_json = item_section_renderer_json["continuationItemRenderer"];
        if(!continuation_item_renderer_json.isObject())
            return "";

        const Json::Value &continuation_endpoint_json = continuation_item_renderer_json["continuationEndpoint"];
        if(!continuation_endpoint_json.isObject())
            return "";

        const Json::Value &continuation_command_json = continuation_endpoint_json["continuationCommand"];
        if(!continuation_command_json.isObject())
            return "";

        const Json::Value &token_json = continuation_command_json["token"];
        if(!token_json.isString())
            return "";
        
        return token_json.asString();
    }

    static void parse_item_section_renderer(const Json::Value &item_section_renderer_json, std::unordered_set<std::string> &added_videos, BodyItems &result_items) {
        const Json::Value &item_contents_json = item_section_renderer_json["contents"];
        if(!item_contents_json.isArray())
            return;

        for(const Json::Value &content_item_json : item_contents_json) {
            if(!content_item_json.isObject())
                continue;

            for(Json::Value::const_iterator it = content_item_json.begin(); it != content_item_json.end(); ++it) {
                Json::Value key = it.key();
                if(key.isString() && strcmp(key.asCString(), "shelfRenderer") == 0) {
                    const Json::Value &shelf_renderer_json = *it;
                    if(!shelf_renderer_json.isObject())
                        continue;

                    const Json::Value &item_content_json = shelf_renderer_json["content"];
                    if(!item_content_json.isObject())
                        continue;

                    const Json::Value &vertical_list_renderer_json = item_content_json["verticalListRenderer"];
                    if(!vertical_list_renderer_json.isObject())
                        continue;

                    const Json::Value &items_json = vertical_list_renderer_json["items"];
                    if(!items_json.isArray())
                        continue;
                    
                    for(const Json::Value &item_json : items_json) {
                        std::shared_ptr<BodyItem> body_item = parse_content_video_renderer(item_json, added_videos);
                        if(body_item)
                            result_items.push_back(std::move(body_item));
                    }
                } else {
                    std::shared_ptr<BodyItem> body_item = parse_content_video_renderer(content_item_json, added_videos);
                    if(body_item)
                        result_items.push_back(std::move(body_item));
                }
            }
        }
    }

    static std::string remove_index_from_playlist_url(const std::string &url) {
        std::string result = url;
        size_t index = result.rfind("&index=");
        if(index == std::string::npos)
            return result;
        return result.substr(0, index);
    }

    static std::shared_ptr<BodyItem> parse_compact_video_renderer_json(const Json::Value &item_json, std::unordered_set<std::string> &added_videos) {
        const Json::Value &compact_video_renderer_json = item_json["compactVideoRenderer"];
        if(!compact_video_renderer_json.isObject())
            return nullptr;

        return parse_common_video_item(compact_video_renderer_json, added_videos);
    }

    SearchResult YoutubeSearchPage::search(const std::string &str, BodyItems &result_items) {
        continuation_token.clear();
        current_page = 0;

        search_url = "https://youtube.com/results?search_query=";
        search_url += url_param_encode(str);

        std::vector<CommandArg> additional_args = {
            { "-H", "x-spf-referer: " + search_url },
            { "-H", "x-youtube-client-name: 1" },
            { "-H", "x-youtube-client-version: 2.20200626.03.00" },
            { "-H", "referer: " + search_url }
        };

        //std::vector<CommandArg> cookies = get_cookies();
        //additional_args.insert(additional_args.end(), cookies.begin(), cookies.end());

        Json::Value json_root;
        DownloadResult result = download_json(json_root, search_url + "&pbj=1", std::move(additional_args), true);
        if(result != DownloadResult::OK) return download_result_to_search_result(result);

        if(!json_root.isArray())
            return SearchResult::ERR;

        std::unordered_set<std::string> added_videos; /* The input contains duplicates, filter them out! */

        for(const Json::Value &json_item : json_root) {
            if(!json_item.isObject())
                continue;

            const Json::Value &response_json = json_item["response"];
            if(!response_json.isObject())
                continue;

            const Json::Value &contents_json = response_json["contents"];
            if(!contents_json.isObject())
                continue;

            const Json::Value &tcsrr_json = contents_json["twoColumnSearchResultsRenderer"];
            if(!tcsrr_json.isObject())
                continue;

            const Json::Value &primary_contents_json = tcsrr_json["primaryContents"];
            if(!primary_contents_json.isObject())
                continue;

            const Json::Value &section_list_renderer_json = primary_contents_json["sectionListRenderer"];
            if(!section_list_renderer_json.isObject())
                continue;
            
            const Json::Value &contents2_json = section_list_renderer_json["contents"];
            if(!contents2_json.isArray())
                continue;
            
            for(const Json::Value &item_json : contents2_json) {
                if(!item_json.isObject())
                    continue;

                if(continuation_token.empty())
                    continuation_token = item_section_renderer_get_continuation_token(item_json);
                
                const Json::Value &item_section_renderer_json = item_json["itemSectionRenderer"];
                if(!item_section_renderer_json.isObject())
                    continue;

                parse_item_section_renderer(item_section_renderer_json, added_videos, result_items);
            }
        }

        return SearchResult::OK;
    }

    PluginResult YoutubeSearchPage::get_page(const std::string &str, int page, BodyItems &result_items) {
        (void)str;
        while(current_page < page) {
            PluginResult plugin_result = search_get_continuation(search_url, continuation_token, result_items);
            if(plugin_result != PluginResult::OK) return plugin_result;
            ++current_page;
        }
        return PluginResult::OK;
    }

    PluginResult YoutubeSearchPage::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<YoutubeVideoPage>(program), nullptr});
        return PluginResult::OK;
    }

    PluginResult YoutubeSearchPage::search_get_continuation(const std::string &url, const std::string &current_continuation_token, BodyItems &result_items) {
        std::string next_url = url + "&pbj=1&ctoken=" + current_continuation_token;

        std::vector<CommandArg> additional_args = {
            { "-H", "x-spf-referer: " + url },
            { "-H", "x-youtube-client-name: 1" },
            { "-H", "x-spf-previous: " + url },
            { "-H", "x-youtube-client-version: 2.20200626.03.00" },
            { "-H", "referer: " + url }
        };

        //std::vector<CommandArg> cookies = get_cookies();
        //additional_args.insert(additional_args.end(), cookies.begin(), cookies.end());

        Json::Value json_root;
        DownloadResult result = download_json(json_root, next_url, std::move(additional_args), true);
        if(result != DownloadResult::OK) return download_result_to_plugin_result(result);

        if(!json_root.isArray())
            return PluginResult::ERR;

        std::unordered_set<std::string> added_videos;
        std::string new_continuation_token;

        for(const Json::Value &json_item : json_root) {
            if(!json_item.isObject())
                continue;

            const Json::Value &response_json = json_item["response"];
            if(!response_json.isObject())
                continue;

            const Json::Value &on_response_received_commands_json = response_json["onResponseReceivedCommands"];
            if(!on_response_received_commands_json.isArray())
                continue;

            for(const Json::Value &response_received_command : on_response_received_commands_json) {
                if(!response_received_command.isObject())
                    continue;

                const Json::Value &append_continuation_items_action_json = response_received_command["appendContinuationItemsAction"];
                if(!append_continuation_items_action_json.isObject())
                    continue;

                const Json::Value &continuation_items_json = append_continuation_items_action_json["continuationItems"];
                if(!continuation_items_json.isArray())
                    continue;

                for(const Json::Value &continuation_item : continuation_items_json) {
                    if(!continuation_item.isObject())
                        continue;

                    if(new_continuation_token.empty()) {
                        // Note: item_section_renderer is compatible with continuation_item
                        new_continuation_token = item_section_renderer_get_continuation_token(continuation_item);
                    }

                    const Json::Value &item_section_renderer_json = continuation_item["itemSectionRenderer"];
                    if(!item_section_renderer_json.isObject())
                        continue;

                    parse_item_section_renderer(item_section_renderer_json, added_videos, result_items);
                }
            }
        }

        if(new_continuation_token.empty())
            continuation_token = std::move(new_continuation_token);

        return PluginResult::OK;
    }

    // TODO: Make this faster by using string search instead of parsing html.
    // TODO: If the result is a play
    BodyItems YoutubeVideoPage::get_related_media(const std::string &url) {
        BodyItems result_items;

        std::string modified_url = remove_index_from_playlist_url(url);
        std::vector<CommandArg> additional_args = {
            { "-H", "x-spf-referer: " + url },
            { "-H", "x-youtube-client-name: 1" },
            { "-H", "x-spf-previous: " + url },
            { "-H", "x-youtube-client-version: 2.20200626.03.00" },
            { "-H", "referer: " + url }
        };

        //std::vector<CommandArg> cookies = get_cookies();
        //additional_args.insert(additional_args.end(), cookies.begin(), cookies.end());

        Json::Value json_root;
        DownloadResult result = download_json(json_root, modified_url + "&pbj=1", std::move(additional_args), true);
        if(result != DownloadResult::OK) return result_items;

        if(!json_root.isArray())
            return result_items;

        std::unordered_set<std::string> added_videos;

        for(const Json::Value &json_item : json_root) {
            if(!json_item.isObject())
                continue;

            const Json::Value &response_json = json_item["response"];
            if(!response_json.isObject())
                continue;

            const Json::Value &contents_json = response_json["contents"];
            if(!contents_json.isObject())
                return result_items;

            const Json::Value &tcwnr_json = contents_json["twoColumnWatchNextResults"];
            if(!tcwnr_json.isObject())
                return result_items;

            const Json::Value &secondary_results_json = tcwnr_json["secondaryResults"];
            if(!secondary_results_json.isObject())
                return result_items;

            const Json::Value &secondary_results2_json = secondary_results_json["secondaryResults"];
            if(!secondary_results2_json.isObject())
                return result_items;
            
            const Json::Value &results_json = secondary_results2_json["results"];
            if(!results_json.isArray())
                return result_items;

            for(const Json::Value &item_json : results_json) {
                if(!item_json.isObject())
                    continue;

                auto body_item = parse_compact_video_renderer_json(item_json, added_videos);
                if(body_item)
                    result_items.push_back(std::move(body_item));
                
                const Json::Value &compact_autoplay_renderer_json = item_json["compactAutoplayRenderer"];
                if(!compact_autoplay_renderer_json.isObject())
                    continue;
                
                const Json::Value &item_contents_json = compact_autoplay_renderer_json["contents"];
                if(!item_contents_json.isArray())
                    continue;
                
                for(const Json::Value &content_item_json : item_contents_json) {
                    if(!content_item_json.isObject())
                        continue;
                    
                    auto body_item = parse_compact_video_renderer_json(content_item_json, added_videos);
                    if(body_item)
                        result_items.push_back(std::move(body_item));
                }
            }
        }

        return result_items;
    }
}