giphyr: R Interface to the Giphy API

# App UI
add_gifs_ui <- miniPage(
  tags$head(
    includeCSS(system.file("gadgets/gif_Addin/app.css", package = "giphyr"))
  ),
  gadgetTitleBar("Add GIFs"),
  miniContentPanel(
    fillRow(flex = c(1, 1, 1, 6, 2, 2, 2), height = "45px",
            uiOutput("back_button"), uiOutput("forward_button"),
            uiOutput("random_button"),
            uiOutput("gif_search_box"),
            uiOutput("download_gif_button"),
            uiOutput("insert_gif_button"),
            uiOutput("insert_link_button")),
    fillRow(flex = c(4, 3, 3), height = "55px",
            uiOutput("rating_ui"),
            uiOutput("citation_ui"),
            uiOutput("size_ui")),
    uiOutput("preview"),
    htmlOutput("space_holder"),
    tags$div(htmlOutput("pagination_note"),
             class = "pagination_note pull-right"),
    tags$div(class = "giphylogo",
             img(src = file.path("rsc/giphy.png"), width = 100))
  ),
  includeScript(system.file("gadgets/gif_Addin/app.js", package = "giphyr"))
)

# App Server
add_gifs_server <- function(input, output, session) {
  output$gif_search_box <- renderUI({
    textInput("search_text", label = NULL,
              placeholder = "Search all the GIFs",
              width = "98%")
  })

  output$download_gif_button <- renderUI({
    actionButton("download_gif",
                 label = HTML('<i class="fa fa-download"></i>'),
                 width = "95%", class = "btn-primary")
  })

  output$insert_gif_button <- renderUI({
    actionButton("insert_gif",
                 label = HTML('<i class="fa fa-download"></i> ',
                              '<i class="fa fa-plus"></i> ',
                              '<i class="fa fa-file-text-o"></i>'),
                 width = "95%", class = "btn-success")
  })

  output$insert_link_button <- renderUI({
    actionButton("insert_link",
                 label = HTML('<i class="fa fa-link"></i> ',
                              '<i class="fa fa-plus"></i> ',
                              '<i class="fa fa-file-text-o"></i>'),
                 width = "95%", class = "btn-default")
  })

  output$back_button <- renderUI({
    actionButton("pagination_back", label = NULL, width = "95%",
                 icon = icon("arrow-left"), title = "Previous Page")
  })

  output$forward_button <- renderUI({
    actionButton("pagination_forward", label = NULL, width = "95%",
                 icon = icon("arrow-right"), title = "Next Page")
  })
  output$random_button <- renderUI({
    actionButton("pagination_random", label = NULL, width = "95%",
                 icon = icon("gift"), title = "Go to a random page")
  })

  output$size_ui <- renderUI({
    radioButtons(
      "size",
      HTML('Size: <sup><i class="fa fa-question-circle-o" title',
           '="medium: max 2mb\nlarge: max 5mb\noriginal: no restriction"></i></sup>'),
      c("medium" = "downsized", "large" = "downsized_medium", "original"),
      inline = T)
  })

  output$rating_ui <- renderUI({
    radioButtons(
      "rating", "Rating:",
      c("G", "Y", "PG", "PG-13", "R"), inline = T
    )
  })

  output$citation_ui <- renderUI({
    radioButtons(
      "citation", "Citation:",
      c("no", "yes", "cite source"), inline = T
    )
  })

  values <- reactiveValues(offset = 0, pre_offsets = c(0), off_position = 1,
                           total_count = 0)

  observeEvent(input$pagination_back, {
    if (values$off_position >= 2) {
      values$off_position <- values$off_position - 1
      values$offset <- values$pre_offsets[values$off_position]
    }
  })

  observeEvent(input$pagination_forward, {
    if (values$off_position == length(values$pre_offsets)) {
      values$offset <- values$offset + 10
      values$pre_offsets <- c(values$pre_offsets, values$offset)
    } else {
      values$offset <- values$pre_offsets[values$off_position + 1]
    }
    values$off_position <- values$off_position + 1
  })

  preview_gifs <- reactive({
    req(input$search_text)
    out <- suppressWarnings(
      gif_search(input$search_text,
                 img_format = c("fixed_height_small", "downsized",
                                "downsized_medium", "original"),
                 offset = values$offset,
                 rating = tolower(input$rating)))
    if (is.null(out)) return(NULL)
    return(out)
  })

  observeEvent(input$search_text, {
    if (!is.null(preview_gifs())) {
      values$total_count <- attr(preview_gifs(), "total_count")
      if (values$total_count > 4999) {
        values$total_count <- 4999
      }
    }
  })

  observeEvent(input$rating, {
    if (!is.null(preview_gifs())) {
      values$total_count <- attr(preview_gifs(), "total_count")
      values$offset <- 0
      values$pre_offsets <- c(0)
      values$off_position <- 1
      if (values$total_count > 4999) {
        values$total_count <- 4999
      }
    }
  })

  observeEvent(input$pagination_random, {
    if (values$off_position != length(values$pre_offsets)) {
      values$pre_offsets <- values$pre_offsets[1:values$off_position]
    }
    values$offset <- sample(10:(values$total_count - 10), 1)
    values$pre_offsets <- c(values$pre_offsets, values$offset)
    values$off_position <- values$off_position + 1
  })

  output$pagination_note <- function() {
    req(preview_gifs())
    page_note <- paste(
      attr(preview_gifs(), "offset") + 1, "~",
      attr(preview_gifs(), "offset") + attr(preview_gifs(), "count"),
      "of", attr(preview_gifs(), "total_count")
    )
    if (values$total_count != attr(preview_gifs(), "total_count")) {
      page_note <- paste(
        page_note,
        '<sup><i class="fa fa-warning small" title="Although we have a lot,',
        'GIPHY API only supports the first 5000 gifs. :P"></i></sup>'
      )
    }
    return(HTML(page_note))
  }

  observeEvent(input$search_text, {
    values$offset = 0
  })

  find_ele <- function(x, name) {
    x_names <- names(x)
    return(x[which(x_names == name)][[1]])
  }

  output$preview <- renderUI({
    req(preview_gifs())
    apply(preview_gifs(), 1, function(x) {
      actionLink(find_ele(x, "id"), title = find_ele(x, "slug"),
                 label = NULL, class = "gifpreview", icon = NULL,
                 tags$img(src = find_ele(x, "fixed_height_small")))
    })
  })

  output$space_holder <- function() {
    if (is.null(input$search_text)) return(NULL)
    if (input$search_text != "") return(NULL)
    app_message <- paste0(
      '<p>Step 1. Search any keywords</p>',
      '<p>Step 2. Select a GIF you like</p>',
      '<p>Step 3. Download it <code><i class="fa fa-download"></i></code> / ',
      'Download & insert it to a Rmd document <code>',
      '<i class="fa fa-download"></i> ',
      '<i class="fa fa-plus"></i> ',
      '<i class="fa fa-file-text-o"></i></code> / ',
      'Simply insert a link to a Rmd document <code>',
      '<i class="fa fa-link"></i> ',
      '<i class="fa fa-plus"></i> ',
      '<i class="fa fa-file-text-o"></i></code>',
      '</p><br>'
    )
    app_tips <- c(
      '<i class="fa fa-gift"></i> will drop you at a random page. Use it to discover more fun gifs!',
      'Unfortunately, GIPHY API can only export the first 5000 gifs. :(',
      'Downloaded GIFs are saved in the "img" folder in your project directory.',
      "For download file sizes, <code>medium</code>: file < 2 MB, <code>large</code>: file < 5 MB & <code>original</code>: no restriction.",
      "If you choose to <code>cite source</code>, be cautious because some links might have been expired after a few years.",
      "Regular citations will direct readers to the image on giphy.com, where they can find source information as well. "
    )
    HTML(
      '<div class="spaceHolder">', app_message,
      'Tip: <br>', app_tips[sample(1:length(app_tips), 1)],
      '</div>'
    )
  }

  observeEvent(input$done, {
    invisible(stopApp())
  })

  observeEvent(input$download_gif, {
    if (!is.null(input$clickedgif) & !is.null(input$search_text)) {
      dir.create("img", showWarnings = F)
      dl_file_name <- paste0(
        "img/", search_query_parser(input$search_text),
        "_", input$clickedgif, ".gif"
      )
      status <- try(download.file(
        preview_gifs()[[input$size]][preview_gifs()$id == input$clickedgif],
        dl_file_name
      ), silent = T)
    }
  })

  observeEvent(input$insert_gif, {
    if (!is.null(input$clickedgif) & !is.null(input$search_text)) {
      dir.create("img", showWarnings = F)
      dl_file_name <- paste0(
        "img/", search_query_parser(input$search_text),
        "_", input$clickedgif, ".gif"
      )
      status <- try(download.file(
        preview_gifs()[[input$size]][preview_gifs()$id == input$clickedgif],
        dl_file_name
      ), silent = T)
      bitly_link <- preview_gifs()$bitly_url[
        preview_gifs()$id == input$clickedgif]
      citation_source <- preview_gifs()$source[
        preview_gifs()$id == input$clickedgif]
      source_date <- preview_gifs()$import_datetime[
        preview_gifs()$id == input$clickedgif]
      citation_text <- switch(
        input$citation,
        "no" = NULL,
        "yes" = paste0("<div style='font-size:50%'>(Available at [",
                       bitly_link, "](", bitly_link, "), ",
                       format(Sys.Date(), "%b %d, %Y"), ")</div>  \n"),
        "cite source" = paste0("<div style='font-size:50%'>([Source link](",
                               citation_source, "), accessed ",
                               format(as.Date(source_date), "%b %d, %Y"),
                               ")</div>  \n")
      )
      if (citation_source == "" & input$citation == "cite source") {
        citation_text <- NULL
        cat("Source info is not available. ")
      }
      rstudioapi::insertText(
        text = paste0('![', search_query_parser(input$search_text), "](",
                      dl_file_name, ")\n", citation_text))
    }
  })

  observeEvent(input$insert_link, {
    if (!is.null(input$clickedgif) & !is.null(input$search_text)) {
      img_link <- preview_gifs()[[input$size]][
        preview_gifs()$id == input$clickedgif]
      bitly_link <- preview_gifs()$bitly_url[
        preview_gifs()$id == input$clickedgif]
      citation_source <- preview_gifs()$source[
        preview_gifs()$id == input$clickedgif]
      source_date <- preview_gifs()$import_datetime[
        preview_gifs()$id == input$clickedgif]
      citation_text <- switch(
        input$citation,
        "no" = NULL,
        "yes" = paste0("<div style='font-size:50%'>(Available at [",
                       bitly_link, "](", bitly_link, "), ",
                       format(Sys.Date(), "%b %d, %Y"), ")</div>  \n"),
        "cite source" = paste0("<div style='font-size:50%'>([Source link](",
                               citation_source, "), accessed ",
                               format(as.Date(source_date), "%b %d, %Y"),
                               ")</div>  \n")
      )
      if (citation_source == "" & input$citation == "cite source") {
        citation_text <- NULL
        cat("Source info is not available. ")
      }
      rstudioapi::insertText(
        text = paste0('![', search_query_parser(input$search_text), "](",
                      img_link, ")  \n", citation_text))
    }
  })
}

#' giphyr RStudio Addin
gif_Addin <- function() {
  addResourcePath("rsc",
                  system.file("gadgets/gif_Addin", package = "giphyr"))
  runGadget(add_gifs_ui, add_gifs_server, viewer = paneViewer())
}

#' Add GIFs through a shiny app
#'
#' @description A shiny app alternative to the RStudio Addin for non-RStudio
#' users.
#'
#' @export
add_gifs <- function() {
  shinyApp(add_gifs_ui, add_gifs_server)
}