#include <nntpchan/staticfile_frontend.hpp>
#include <nntpchan/file_handle.hpp>
#include <nntpchan/sanitize.hpp>
#include <nntpchan/mime.hpp>
#include <nntpchan/sha1.hpp>
#include <any>
#include <iostream>
#include <set>
#include <sstream>

namespace nntpchan
{


  StaticFileFrontend::StaticFileFrontend(TemplateEngine * tmpl, const std::string & templateDir, const std::string & outDir, uint32_t pages) :
    m_TemplateEngine(tmpl),
    m_TemplateDir(templateDir),
    m_OutDir(outDir),
    m_Pages(pages)
  {
  }

  void StaticFileFrontend::ProcessNewMessage(const fs::path & fpath)
  {
    std::clog << "process message " << fpath << std::endl;
    auto file = OpenFile(fpath, eRead);
    if(file)
    {
      // read header
      RawHeader header;
      if(!ReadHeader(file, header))
      {
        std::clog << "failed to read mime header" << std::endl;
        return;
      }

      // read body

      std::map<std::string, std::any> thread_args;
      
      auto findMsgidFunc = [](const std::pair<std::string, std::string> & item) -> bool {
        auto lower = ToLower(item.first);
        return (lower == "message-id") || (lower == "messageid");
      };
      
      auto msgid = std::find_if(header.begin(), header.end(), findMsgidFunc);
      
      if(!IsValidMessageID(msgid->second))
      {
        std::clog << "invalid message-id: " << msgid->second << std::endl;
        return;
      }
        
      std::string msgid_hash = sha1_hex(msgid->second);
        
      fs::path threadFilePath = m_OutDir / fs::path("thread-" + msgid_hash + ".html");
      if(m_TemplateEngine)
      {
        FileHandle_ptr out = OpenFile(threadFilePath, eWrite);
        if(!m_TemplateEngine->WriteTemplate("thread.mustache", thread_args, out))
        {
          std::clog << "failed to write " << threadFilePath << std::endl;
          return;
        }
      }
      std::set<std::string> newsgroups_list;
      
      auto findNewsgroupsFunc = [](const std::pair<std::string, std::string> & item) -> bool
      {
        return ToLower(item.first) == "newsgroups";
      };

      auto group = std::find_if(header.begin(), header.end(), findNewsgroupsFunc);
      if(group == std::end(header))
      {
        std::clog << "no newsgroups header" << std::endl;
        return;
      }
      std::istringstream input(group->second);
      
      std::string newsgroup;
      while(std::getline(input, newsgroup, ' '))
      {
        if(IsValidNewsgroup(newsgroup))
          newsgroups_list.insert(newsgroup);
      }
      
      for(const auto & name : newsgroups_list)
      {
        auto board = GetThreadsPaginated(name, 10, m_Pages);
        uint32_t pageno = 0;
        for(Threads_t threads : board)
        {
          std::map<std::string, std::any> board_args;
          board_args["group"] = std::make_any<std::string>(name);
          board_args["pageno"] = std::make_any<uint32_t>(pageno);
          board_args["threads"] = std::make_any<Threads_t>(threads);
          
          fs::path boardPageFilename(newsgroup + "-" + std::to_string(pageno) + ".html");
          if(m_TemplateEngine)
          {
            FileHandle_ptr out = OpenFile(m_OutDir / boardPageFilename, eWrite);
            m_TemplateEngine->WriteTemplate("board.mustache", board_args, out);
          }
          
          ++pageno;
        }
      }
    }
  }


  bool StaticFileFrontend::AcceptsNewsgroup(const std::string & newsgroup)
  {
    return IsValidNewsgroup(newsgroup);
  }

  bool StaticFileFrontend::AcceptsMessage(const std::string & msgid)
  {
    return IsValidMessageID(msgid);
  }
  
  StaticFileFrontend::BoardPage_t StaticFileFrontend::GetThreadsPaginated(const std::string & group, uint32_t perpage, uint32_t pages)
  {
    return {};
  }
}