const os = require('os');
const path = require('path');
const fs = require('fs');

const { ipcRenderer } = require('electron');

exports.api_token_request_async = async function (axios, secret_key) {
  console.log('Requesting API temporary token...');
  const url = '/api_token_request';
  
  let data = { secret_key: secret_key };
  
  const response = await axios.post(url, data)
    .then(function (response) {
      //console.log(response);
      const api_temporary_token = response.data.temporary_token;
      //console.log('API Temporary Token: '+temporary_token);
      return api_temporary_token;
    })
    .catch(function (error) {
      console.error(error);
      return error;
    });
  return response;
}


exports.get_event_details = async function (axios, event_id) {
  console.log('Requesting event details...');
  const url = '/event/'+event_id;
  
  const data = await axios.get(url)
    .then(function (response) {
      //console.log(response.data);
      //data = response.data;
      return response.data;
    })
    .catch(function (error) {
      console.log(error);
      return error;
    });
  
  return data;
}


exports.get_event_location_details = async function (axios, event_id, event_location_id) {
  console.log('Requesting event location details...');
  const url = '/event/'+event_id+'/location/'+event_location_id;
  
  const data = await axios.get(url)
    .then(function (response) {
      //console.log(response.data);
      //data = response.data;
      return response.data;
    })
    .catch(function (error) {
      console.log(error);
      return error;
    });
  
  return data;
}


exports.get_event_location_sessions = async function (axios, event_id, event_location_id) {
  console.log('Requesting location sessions...');
  const url = '/event/'+event_id+'/location/'+event_location_id+'/session';
  
  const data = await axios.get(url)
    .then(function (response) {
      //console.log(response.data);
      //data = response.data;
      return response.data;
    })
    .catch(function (error) {
      console.log(error);
      return error;
    });
  
  return data;
}


exports.get_session_presentations = async function (axios, event_id, event_session_id) {
  console.log('Requesting session presentations...');
  const url = '/event/'+event_id+'/session/'+event_session_id+'/presentation';
  
  const data = await axios.get(url)
    .then(function (response) {
      //console.log(response.data);
      //data = response.data;
      return response.data;
    })
    .catch(function (error) {
      console.log(error);
      return error;
    });
  
  return data;
}


exports.get_presentation_presenters = async function (axios, event_id, event_session_id, event_presentation_id) {
  console.log('Requesting presentation presenters...');
  const url = '/event/'+event_id+'/session/'+event_session_id+'/presentation/'+event_presentation_id+'/presenter';
  
  const data = await axios.get(url)
    .then(function (response) {
      //console.log(response.data);
      //data = response.data;
      return response.data;
    })
    .catch(function (error) {
      console.log(error);
      return error;
    });
  
  return data;
}


exports.get_files_for_type_for_id = async function (axios, for_type, for_id) {
  console.log('Requesting files for '+for_type+' '+for_id);
  const url = '/event/file/'+for_type+'/'+for_id;
  
  const data = await axios.get(url)
    .then(function (response) {
      //console.log(response.data);
      //data = response.data;
      return response.data;
    })
    .catch(function (error) {
      console.log(error);
      return error;
    });
  
  return data;
}


exports.download_file_id = async function (axios, file_id, filename) {
  
  ipcRenderer.send('download_file', api_base_url, api_endpoint, api_temporary_token, save_path); // in render thread
  
  console.log('1: download file id '+file_id);
  const url = '/event/file/'+file_id+'/download';
  
  //const data = await axios.get(url, responseType: 'stream')
  const data = await axios({
    method: "get",
    url: url,
    responseType: "stream"
  })
    .then(function (response) {
      console.log('2: downloaded file id '+file_id);
      console.log(response);
      //console.log(response.data);
      
      let filename = 'default.txt';
      
      if (typeof filename_override === 'undefined' || filename_override == null) {
        let headerLine = response.data.headers['content-disposition'];
        
        console.log(headerLine);
        console.log(headerLine.indexOf('="'));
        console.log(headerLine.indexOf('='));
        if (headerLine.indexOf('="') != -1) {
          let startFileNameIndex = headerLine.indexOf('="') + 2;
          let endFileNameIndex = headerLine.lastIndexOf('"');
          filename = headerLine.substring(startFileNameIndex, endFileNameIndex);
        } else if (headerLine.indexOf('=') != -1) {
          let startFileNameIndex = headerLine.indexOf('=') + 1;
          let endFileNameIndex = headerLine.length;
          filename = headerLine.substring(startFileNameIndex, endFileNameIndex);
        } else {
          filename = 'filename_not_found_in_header.txt';
        }
      } else {
        filename = filename_override;
      }

      let directory = 'file_cache/';
      
      directory_and_filename = path.join(directory, filename);
      
      //console.log(directory_and_filename);
      
      if (fs.existsSync(directory_and_filename)) {
        console.log('3a: file already exists: '+directory_and_filename);
      } else {
        console.log('3b: saving file: '+directory_and_filename);
        response.data.pipe(fs.createWriteStream(directory_and_filename));
      }
      //data = response.data;
      console.log('4: saved file id '+file_id);
      return true;
      //return response.data;
    })
    .catch(function (error) {
      console.log(error);
      return error;
    });
  
  //return data;
}

exports.launcher_cache_check = async function (launcher, api_base_url, api_temporary_token, file_cache_path) {
  
  if (typeof launcher.event === 'undefined') {
    launcher.event = await api.get_event_details(axios, launcher.event_id);
    console.log(launcher.event.id);
    idbKeyval.set(launcher.event.id, launcher.event, db_event);
    /*
    .then(function (data) {
      console.log(data.id);
      idbKeyval.set(data.id, data, db_event);
      //for (var i in response) {
        //var event_record = data[i];
        //idbKeyval.set(response[i].id, response[i], db_event);
      //}
    });
    */
    
  }
  
  if (typeof launcher.location === 'undefined') {
    launcher.location = await api.get_event_location_details(axios, launcher.event_id, launcher.event_location_id);
  }
  
  if (typeof launcher.event_files === 'undefined') {
    console.log('Check for global event files.');
    let for_id = launcher.event_id;
    launcher.event_files = await api.get_files_for_type_for_id(axios, 'event', for_id);
    for (var i in launcher.event_files) {
      console.log('f: ('+launcher.event_files[i].event_file_id+') '+launcher.event_files[i].event_file_filename+' ***')
      file_id = launcher.event_files[i].event_file_id; // NOTE: the .id is the hosted_file.id!
      let filename = launcher.event_files[i].hash_sha256+'.file';
      
      save_path = path.join(file_cache_path, filename);
      
      if (fs.existsSync(save_path)) {
        console.log('Local file already exists: '+save_path);
      } else {
        console.log('File not found locally. Downloading file: '+save_path);
        let api_endpoint = '/event/file/'+file_id+'/download';
        ipcRenderer.send('download_file', api_base_url, api_endpoint, api_temporary_token, save_path); // Must download file using main node.js thread.
      }
    }
  } else {
    console.log('No check for global event files');
  }
  
  
  if (typeof launcher.location_files === 'undefined') {
    console.log('Check for location specific files.');
    let for_id = launcher.event_location_id;
    launcher.location_files = await api.get_files_for_type_for_id(axios, 'location', for_id);
    for (var i in launcher.location_files) {
      console.log('f: ('+launcher.location_files[i].event_file_id+') '+launcher.location_files[i].event_file_filename+' ***')
      file_id = launcher.location_files[i].event_file_id; // NOTE: the .id is the hosted_file.id!
      let filename = launcher.location_files[i].hash_sha256+'.file';
      
      save_path = path.join(file_cache_path, filename);
      
      if (fs.existsSync(save_path)) {
        console.log('Local file already exists: '+save_path);
      } else {
        console.log('File not found locally. Downloading file: '+save_path);
        let api_endpoint = '/event/file/'+file_id+'/download';
        ipcRenderer.send('download_file', api_base_url, api_endpoint, api_temporary_token, save_path); // Must download file using main node.js thread.
      }
    }
  } else {
    console.log('No check for location specific files.');
  }
  
  
  if (typeof launcher.sessions === 'undefined') {
    console.log('Check for location sessions.');
    launcher.sessions = await api.get_event_location_sessions(axios, launcher.event_id, launcher.event_location_id);
    for (var i in launcher.sessions) {
      console.log('*** '+launcher.sessions[i].name+' ***')
      
      // Check for session files start
      if (typeof launcher.sessions[i].files === 'undefined') {
        console.log('Check for session files.');
        let for_id = launcher.sessions[i].id;
        launcher.sessions[i].files = await api.get_files_for_type_for_id(axios, 'session', for_id);
        if (launcher.sessions[i].files) {
          console.log('Session files found.');
          for (var j in launcher.sessions[i].files) {
            console.log('f: ('+launcher.sessions[i].files[j].event_file_id+') '+launcher.sessions[i].files[j].event_file_filename+' ***');
            file_id = launcher.sessions[i].files[j].event_file_id; // NOTE: the .id is the hosted_file.id!
            let filename = launcher.sessions[i].files[j].hash_sha256+'.file';
            
            save_path = path.join(file_cache_path, filename);
            
            if (fs.existsSync(save_path)) {
              console.log('Local file already exists: '+save_path);
            } else {
              console.log('File not found locally. Downloading file: '+save_path);
              let api_endpoint = '/event/file/'+file_id+'/download';
              ipcRenderer.send('download_file', api_base_url, api_endpoint, api_temporary_token, save_path); // Must download file using main node.js thread.
            }
          }
        } else {
          console.log('No session files found.');
        }
      } else {
        console.log('No check for session files.');
      }
      // Check for session files end
      
      // Get session presentations and associated files
      launcher.sessions[i].presentations = await api.get_session_presentations(axios, launcher.event_id, launcher.sessions[i].id);
      for (var j in launcher.sessions[i].presentations) {
        console.log('* '+launcher.sessions[i].presentations[j].name);
        
        // Check for presentation files start
        if (typeof launcher.sessions[i].presentations[j].files === 'undefined') {
          console.log('Check for presentation files.');
          let for_id = launcher.sessions[i].presentations[j].id;
          launcher.sessions[i].presentations[j].files = await api.get_files_for_type_for_id(axios, 'presentation', for_id);
          if (launcher.sessions[i].presentations[j].files) {
            console.log('Presentation files found.');
            for (var k in launcher.sessions[i].presentations[j].files) {
              console.log('f: ('+launcher.sessions[i].presentations[j].files[k].event_file_id+') '+launcher.sessions[i].presentations[j].files[k].event_file_filename+' ***');
              file_id = launcher.sessions[i].presentations[j].files[k].event_file_id; // NOTE: the .id is the hosted_file.id!
              let filename = launcher.sessions[i].presentations[j].files[k].hash_sha256+'.file';
              
              save_path = path.join(file_cache_path, filename);
              
              if (fs.existsSync(save_path)) {
                console.log('Local file already exists: '+save_path);
              } else {
                console.log('File not found locally. Downloading file: '+save_path);
                let api_endpoint = '/event/file/'+file_id+'/download';
                ipcRenderer.send('download_file', api_base_url, api_endpoint, api_temporary_token, save_path); // Must download file using main node.js thread.
              }
            }
          } else {
            console.log('No presentation files found.');
          }
        } else {
          console.log('No check for presentation files.');
        }
        // Check for presentation files end
        
        
        // Get session presentations presenters and associated files
        //let event_presentation_id = launcher.sessions[i].presentations[j].id;
        launcher.sessions[i].presentations[j].presenters = await api.get_presentation_presenters(axios, launcher.event_id, launcher.sessions[i].id, launcher.sessions[i].presentations[j].id);
        for (var k in launcher.sessions[i].presentations[j].presenters) {
          console.log('-- '+launcher.sessions[i].presentations[j].presenters[k].given_name+' '+launcher.sessions[i].presentations[j].presenters[k].family_name)
          
          // Check for presenter files start
          if (typeof launcher.sessions[i].presentations[j].presenters[k].files === 'undefined') {
            console.log('Check for presenter files.');
            let for_id = launcher.sessions[i].presentations[j].presenters[k].id;
            launcher.sessions[i].presentations[j].presenters[k].files = await api.get_files_for_type_for_id(axios, 'presenter', for_id);
            if (launcher.sessions[i].presentations[j].presenters[k].files) {
              console.log('Presenter files found.');
              for (var l in launcher.sessions[i].presentations[j].presenters[k].files) {
                console.log('f: ('+launcher.sessions[i].presentations[j].presenters[k].files[l].event_file_id+') '+launcher.sessions[i].presentations[j].presenters[k].files[l].event_file_filename+' ***')
                file_id = launcher.sessions[i].presentations[j].presenters[k].files[l].event_file_id; // NOTE: the .id is the hosted_file.id!
                let filename = launcher.sessions[i].presentations[j].presenters[k].files[l].hash_sha256+'.file';
                
                save_path = path.join(file_cache_path, filename);
                
                if (fs.existsSync(save_path)) {
                  console.log('Local file already exists: '+save_path);
                } else {
                  console.log('File not found locally. Downloading file: '+save_path);
                  let api_endpoint = '/event/file/'+file_id+'/download';
                  ipcRenderer.send('download_file', api_base_url, api_endpoint, api_temporary_token, save_path); // Must download file using main node.js thread.
                }
              }
            } else {
              console.log('No presenter files found.');
            }
          } else {
            console.log('No check for presenter files.');
          }
          // Check for presenter files end
          
        }
      }
    }
  } else {
    console.log('No check for location sessions.');
  }
  
  console.log('Location cache check finished.');
  return true;
}

exports.launcher_render = async function (launcher) {
  console.log('Rendering launcher...');
  document.getElementById('location_title').innerHTML = '<h1>Launcher '+launcher.location.name+'@'+launcher.event.name+'</h1>';
  
  document.getElementById('event_files_menu').innerHTML = '<h2>Event Files</h2>';
  document.getElementById('event_files_menu').innerHTML += '<ul class="">';
  for (var i in launcher.event_files) {
    document.getElementById('event_files_menu').innerHTML += '<li id="menu_event_file_id_'+launcher.event_files[i].id+'" class="btn btn-info btn_no_case open_local_file" data-hash_sha256="'+launcher.event_files[i].hash_sha256+'.file" data-filename="'+launcher.event_files[i].event_file_filename+'">'+launcher.event_files[i].event_file_filename+'</li>';
  }
  document.getElementById('event_files_menu').innerHTML += '</ul>';
  
  document.getElementById('location_files_menu').innerHTML = '<h2>Location Files</h2>';
  document.getElementById('location_files_menu').innerHTML += '<ul class="" role="">';
  for (var i in launcher.location_files) {
    document.getElementById('location_files_menu').innerHTML += '<li id="menu_event_file_id_'+launcher.location_files[i].id+'" class="btn btn-info open_local_file" data-hash_sha256="'+launcher.location_files[i].hash_sha256+'.file" data-filename="'+launcher.location_files[i].event_file_filename+'">'+launcher.location_files[i].event_file_filename+'</li>';
  }
  document.getElementById('location_files_menu').innerHTML += '</ul>';
  
  document.getElementById('sessions_menu').innerHTML = '<h2>Sessions</h2>';
  document.getElementById('sessions_menu').innerHTML += '<ul class="" role="">';
  //let location_detail = '';
  if (document.getElementById('location_detail').innerHTML.length) {
    console.log('detail_session_id_xx already exists');
  } else {
    console.log('location_detail already populated');
    document.getElementById('location_detail').innerHTML = ''; // This needs to be reviewed.
  }
  for (var i in launcher.sessions) {
    // List sessions in menu
    document.getElementById('sessions_menu').innerHTML += '<li id="menu_session_id_'+launcher.sessions[i].id+'" class="btn btn-info btn_view_session" data-session_id="'+launcher.sessions[i].id+'">'+launcher.sessions[i].name+'</li>';
    
    // Create containers for each session
    let session_detail = '';
    
    if (typeof(document.getElementById('detail_session_id_'+launcher.sessions[i].id)) != 'undefined' && document.getElementById('detail_session_id_'+launcher.sessions[i].id) != null) {
      //console.log('detail_session_id_xx already exists');
    } else {
      //console.log('Adding detail_session_id_xx');
      session_detail += '<div id="detail_session_id_'+launcher.sessions[i].id+'" class="container d-none session_detail" data-session_id="'+launcher.sessions[i].id+'">';
    }
    
    
    
    var session_startdatetime = new Date(launcher.sessions[i].start_datetime);
    
    session_detail += '<h2 class="session_title">'+launcher.sessions[i].name+'<span class="badge badge-pill badge-info float-right">'+dateFns.format(session_startdatetime, 'ddd h:mm A')+'</span>'+'</h2>';
    
    
    //session_detail += '<div class="">'; // for card-group
      
      session_detail += '<div class="card">';
      session_detail += '<div class="card-header">Session Files:</div>';
      session_detail += '<div class="card-body">';
      
      session_detail += '<ul>';
      for (var j in launcher.sessions[i].files) {
        //console.log(launcher.sessions[i].files[j].event_file_filename);
        session_detail += '<li class="btn btn-info open_local_file" data-hash_sha256="'+launcher.sessions[i].files[j].hash_sha256+'.file" data-filename="'+launcher.sessions[i].files[j].event_file_filename+'">'+launcher.sessions[i].files[j].event_file_filename+'</li>';
      }
      session_detail += '</ul>';
      
      session_detail += '</div>'; // for card-body
      session_detail += '</div> <!-- for session files card -->'; // for session files card
      
      
      //session_detail += '<div class="session_presentations">';
      
      for (var j in launcher.sessions[i].presentations) {
        //session_detail += '<li>'+launcher.sessions[i].presentations[j].name;
        
        var session_presentation_startdatetime = new Date(launcher.sessions[i].presentations[j].start_datetime);
        
        session_detail += '<div class="card">';
        session_detail += '<div class="card-header">'+launcher.sessions[i].presentations[j].name+'<span class="badge badge-pill badge-info float-right">'+dateFns.format(session_startdatetime, 'h:mm a')+'</span>'+':</div>';
        session_detail += '<div class="card-body">';
        
        session_detail += '<ul class="list-group">';
        for (var k in launcher.sessions[i].presentations[j].files) {
          //console.log(launcher.sessions[i].presentations[j].files[k].event_file_filename);
          session_detail += '<li class="list-group-item btn btn-info open_local_file" data-hash_sha256="'+launcher.sessions[i].presentations[j].files[k].hash_sha256+'.file" data-filename="'+launcher.sessions[i].presentations[j].files[k].event_file_filename+'">'+launcher.sessions[i].presentations[j].files[k].event_file_filename+'</li>';
        }
        session_detail += '</ul>';
        
        
        session_detail += '<ul>';
        for (var k in launcher.sessions[i].presentations[j].presenters) {
          //console.log(launcher.sessions[i].presentations[j].presenters[k].given_name);
          session_detail += '<li>'+launcher.sessions[i].presentations[j].presenters[k].given_name+' '+launcher.sessions[i].presentations[j].presenters[k].family_name;
          
          session_detail += '<ul class="list-group">';
          for (var l in launcher.sessions[i].presentations[j].presenters[k].files) {
            //console.log(launcher.sessions[i].presentations[j].presenters[k].files[l].event_file_filename);
            //session_detail += '<li class="list-group-item" data-hash_sha256="'+launcher.sessions[i].presentations[j].presenters[k].files[l].hash_sha256+'.file" data-filename="'+launcher.sessions[i].presentations[j].presenters[k].files[l].event_file_filename+'">'+launcher.sessions[i].presentations[j].presenters[k].files[l].event_file_filename;
            session_detail += '<li class="list-group-item" data-hash_sha256="'+launcher.sessions[i].presentations[j].presenters[k].files[l].hash_sha256+'.file" data-filename="'+launcher.sessions[i].presentations[j].presenters[k].files[l].event_file_filename+'">';
            session_detail += '<button class="btn btn-info open_local_file" data-hash_sha256="'+launcher.sessions[i].presentations[j].presenters[k].files[l].hash_sha256+'.file" data-filename="'+launcher.sessions[i].presentations[j].presenters[k].files[l].event_file_filename+'">'+launcher.sessions[i].presentations[j].presenters[k].files[l].event_file_filename+'</button>';
            
            var event_file_size = launcher.sessions[i].presentations[j].presenters[k].files[l].size;
            var event_file_created_on = new Date(launcher.sessions[i].presentations[j].presenters[k].files[l].created_on);
            
            session_detail += '<span class="badge badge-pill badge-light float-right">'+format_bytes(event_file_size, 2)+'; '+dateFns.format(event_file_created_on, 'MMM M h:mm A')+'; '+launcher.sessions[i].presentations[j].presenters[k].files[l].internal_os+'</span>';
            
            
            session_detail += '</li>';
          }
          session_detail += '</ul>';
          
          session_detail +='</li>';
        }
        session_detail += '</ul>';
        
        
        session_detail += '</ul>';
        session_detail += '</div>'; // for card-body
        session_detail += '</div> <!-- for card -->'; // for card
        
      }
      //session_detail += '</div> <!-- for session_presentations -->'; // for session_presentations
      
    //session_detail += '</div>'; // for card-group
    session_detail += '</div> <!-- End session detail for '+launcher.sessions[i].id+' -->';
    
    
    //document.getElementById('location_detail').innerHTML += session_detail;
    
    if (typeof(document.getElementById('detail_session_id_'+launcher.sessions[i].id))  != 'undefined' && document.getElementById('detail_session_id_'+launcher.sessions[i].id) != null) {
      document.getElementById('detail_session_id_'+launcher.sessions[i].id).innerHTML = session_detail;
    } else {
      document.getElementById('location_detail').innerHTML += session_detail;
    }
    
    
  }
  document.getElementById('sessions_menu').innerHTML += '</ul>';
  
  index_location_detail('btn_view_session');
  
  index_open_file_buttons('open_local_file');

  
  //const btn_session_{{ event_presentation.id }}_name = document.querySelector('button#presentation_{{ event_presentation.id }}_name');
  //btn_presentation_{{ event_presentation.id }}_name.onclick = display_hide_poster_for_type_id.bind(this, true, 'presentation', {{ event_presentation.id }});
  console.log('Rendering launcher finished.');
  
  return true;
}


/* Updated 2019-12-19 */
function index_location_detail(class_name) {
  var class_elements = document.getElementsByClassName(class_name);
  
  for (var i = 0; i < class_elements.length; i++) {
    class_elements[i].addEventListener( 'click', function() {view_session( this.getAttribute('data-session_id')) } );
  }
  
  return true;
}


/* Updated 2019-12-19 */
function view_session(session_id) {
  var class_elements = document.getElementsByClassName('session_detail');
  console.log('*** Session ID: '+session_id);
  for (var i = 0; i < class_elements.length; i++) {
    console.log('*** checking: '+class_elements[i].getAttribute('data-session_id'));
    if (class_elements[i].getAttribute('data-session_id') == session_id) {
      console.log('show');
      class_elements[i].classList.remove('d-none');
      class_elements[i].classList.add('d-block');
    } else {
      console.log('hide');
      class_elements[i].classList.remove('d-block');
      class_elements[i].classList.add('d-none');
    }
  }
  
  return true;
}





/* Updated 2019-12-20 */
function index_open_file_buttons(class_name) {
  var class_elements = document.getElementsByClassName(class_name);
  
  for (var i = 0; i < class_elements.length; i++) {
    //class_elements[i].addEventListener( 'click', function() {open_local_file( this.getAttribute('data-filename')) } );
    
    //let directory = 'file_cache/';
    
    //directory_and_filename = path.join(directory, class_elements[i].getAttribute('data-filename'));
    
    let file_path = path.join(file_cache_path, class_elements[i].getAttribute('data-hash_sha256'));
    let filename = class_elements[i].getAttribute('data-filename');
    
    class_elements[i].addEventListener( 'click', function() { ipcRenderer.send('open_local_file', file_path, filename) } );
    //ipcRenderer.send('open_local_file', this.getAttribute('data-filename')); // in render thread
  }
  
  return true;
}



function format_bytes(bytes, decimals = 2) {
    if (bytes === 0) return '0 Bytes';

    const k = 1024;
    const dm = decimals < 0 ? 0 : decimals;
    const sizes = ['Bytes', 'KB', 'MB', 'GB', 'TB', 'PB', 'EB', 'ZB', 'YB'];

    const i = Math.floor(Math.log(bytes) / Math.log(k));

    return parseFloat((bytes / Math.pow(k, i)).toFixed(dm)) + ' ' + sizes[i];
}