rptr: Creates Statistical Reports

#' @title
#' Write a PDF report to the file system
#'
#' @description
#' This function writes a report_spec object to the file system, using the
#' parameters provided in the object.
#'
#' @param x The report_spec object to write.
#' @return The report spec.
#' @noRd
write_report_pdf <- function(rs) {
  
  
  if (file.exists(rs$modified_path))
    file.remove(rs$modified_path)
  
  
  # Create text output 
  res <- create_report_text(rs)
  
  rs <- res[["rs"]]
  ls <- res[["ls"]]

  # Revise text and write to pdf
  fls <- write_pdf_output(rs, ls, rs$modified_path)
  
  return(rs)
}

#' @noRd
write_pdf_output <- function(rs, ls, pdf_path) {
  
  pgs <- list()
  pg <- list(text = c(), images = c())

  # Loop through text pages
  for (i in seq_along(ls)) {
  
    
    # Replace fill lines with blanks
    if (rs$has_graphics) {
      
      ls[[i]] <- gsub("```fill```", "", ls[[i]], fixed = TRUE)
      
      # Need to split up text and images
      for (ln in ls[[i]]) {
        
        res <- grep("```([^}]*)```", ln)
        if (length(res) > 0) {
          pg$text <- append(pg$text, "")
          pi <- parse_image(ln)
          pi$line_start <- length(pg$text)
          pg$images[[length(pg$images) + 1]] <- pi
        } else {
          pg$text <- append(pg$text, ln)   
        }
        
      }
      
    } else 
      pg$text <- ls[[i]]
    

    
    pgs[[length(pgs) + 1]] <- pg
    pg <- list(text = c(), images = c())
  }
  
  
  if (file.exists(pdf_path))
    file.remove(pdf_path)
  
  r <- create_pdf(filename = pdf_path,
                  margin_top = rs$margin_top,
                  margin_left = rs$margin_left,
                  fontsize = rs$font_size,
                  fontname = rs$font,
                  page_height = rs$page_size[2],
                  page_width = rs$page_size[1],
                  orientation = rs$orientation,
                  units = rs$units,
                  info = TRUE)
  
  for (pg in pgs) {
    
    if (length(pg$images) > 0) {
      
      imgs <- list()
      for (img in pg$images) {

        imgs[[length(imgs) + 1]] <- page_image(img$filename,
                                             height = img$height,
                                             width = img$width,
                                             align = img$align,
                                             line_start = img$line_start)
                  
      }
     
      r <- add_page(r, page_text(pg$text), imgs)
                    
    } else {
      r <- add_page(r, page_text(pg$text)) 
    }
  }
  
  
  write_pdf(r)
  
  
  return(pdf_path)
  
}

parse_image <- function(image_string) {
 
  ret <- list()
  
  # Remove braces
  rw <- trimws(gsub("`", "", image_string, fixed = TRUE))  
  
  # Split on pipe
  spec <- strsplit(rw, "|", fixed = TRUE)[[1]]
  
  pth <- gsub("\\", "/", spec[[1]], fixed = TRUE)
  
  # 1 = path
  # 2 = height
  # 3 = width
  # 4 = align 
  
  ret$filename <- pth
  ret$height <- as.numeric(spec[[2]])
  ret$width <- as.numeric(spec[[3]])
  ret$align <- spec[[4]]
  
  return(ret)
  
}

# Old rmarkdown version. Keep for now.
# @noRd
# write_pdf_output2 <- function(rs, ls, rmd_path, pdf_path, tmp_dir) {
#   
#   # Set up vectors
#   hdr <- c() 
#   body <- c() 
#   ret <- c()
#   
#   # Prepare header
#   hdr[length(hdr) + 1] <- "---"
#   hdr[length(hdr) + 1] <- "output:"
#   hdr[length(hdr) + 1] <- "  pdf_document:"
#   hdr[length(hdr) + 1] <- "    latex_engine: xelatex"
#   if (rs$orientation == "landscape") {
#     hdr[length(hdr) + 1] <- "classoption: landscape"
#   } # default if portrait
#   
#   if (rs$font_size == 10)
#     hdr[length(hdr) + 1] <- "fontsize: 10pt"
#   else if (rs$font_size == 12)
#     hdr[length(hdr) + 1] <- "fontsize: 12pt"
#   # if (rs$font_size == 8)
#   #   hdr[length(hdr) + 1] <- "classoption: 8pt"
# 
# 
#   
#   # "left=3cm,right=3cm,top=2cm,bottom=2cm"
#   if (rs$units == "inches") {
#     geom <- paste0(" \"left=", sprintf("%.3f", rs$margin_left * .80), 
#                    "in, right=", sprintf("%.3f", rs$margin_right * .65), 
#                    "in, top=", sprintf( "%.3f", rs$margin_top * .85), 
#                    "in, bottom=", sprintf("%.3f", rs$margin_bottom/2), "in\"")
#   } else {
#     geom <- paste0("\"left=", rs$margin_left * .80, "cm, right=", 
#                    rs$margin_right  * .65, "cm, top=", rs$margin_top * .85, 
#                    "cm, bottom=", rs$margin_bottom/2, "cm\"")
#   }
#   hdr[length(hdr) + 1] <- paste("geometry:", geom)
#   # Figure out paper size options
#   if (rs$paper_size == "letter")
#     hdr[length(hdr) + 1] <- "papersize: letter"
#   else if (rs$paper_size == "A4")
#     hdr[length(hdr) + 1] <- "papersize: a4"
#   hdr[length(hdr) + 1] <- "header-includes:"
#   if (rs$font_size == 8)
#     hdr[length(hdr) + 1] <- "  - \\usepackage[fontsize=8pt]{scrextend}"
#   hdr[length(hdr) + 1] <- "  - \\renewcommand{\\familydefault}{\\ttdefault}"
#   hdr[length(hdr) + 1] <- "  - \\thispagestyle{empty}"
#   hdr[length(hdr) + 1] <- "---"
# 
#   hdr[length(hdr) + 1] <- "\\pagenumbering{gobble}"
#   hdr[length(hdr) + 1] <- "\\begin{verbatim}"
# 
#   # Start with all lines
#   body <- ls
#   
#   if (rs$has_graphics) {
#     # Remove fill lines
#     fill_tags <- grep("```fill```", body, fixed = TRUE)
#     body <- body[-fill_tags]
#     
#     # Replace any plot tags with latex codes
#     plt_tags <- grep("```([^}]*)```", body)
#     
#     for (i in plt_tags) {
#       
#       # Remove braces
#       rw <- trimws(gsub("`", "", body[i], fixed = TRUE))  
#       
#       # Split on pipe
#       spec <- strsplit(rw, "|", fixed = TRUE)[[1]]
#       
#       pth <- gsub("\\", "/", spec[[1]], fixed = TRUE)
#       ret[length(ret) + 1] <- pth
#   
#       # 1 = path
#       # 2 = height
#       # 3 = width
#       # 4 = align
#       
#       # Create latex codes
#       if (spec[[4]] == "left") {
#         ltx <- paste0("\\end{verbatim}\n",
#                       "\\begin{figure}[h!]\n",
#                       "\\begin{flushleft}\n", 
#                       "\\includegraphics{", pth, "}\n",
#                       "\\end{flushleft}\n",
#                       "\\end{figure}\n",
#                       "\\begin{verbatim}")
#         
#       } else if (spec[[4]] == "right") {
#         ltx <- paste0("\\end{verbatim}\n",
#                       "\\begin{figure}[h!]\n",
#                        "\\begin{flushright}\n", 
#                        "\\includegraphics{", pth, "}\n",
#                        "\\end{flushright}\n",
#                        "\\end{figure}\n",
#                        "\\begin{verbatim}")
#       } else  {
#       ltx <- paste0("\\end{verbatim}\n",
#                     "\\begin{figure}[h!]\n",
#                     "\\centering\n", 
#                     "\\includegraphics{", pth, "}\n",
#                     "\\end{figure}\n",
#                     "\\begin{verbatim}")
#       }
#       
#       # Replace original line with latex codes
#       body[[i]] <- ltx
#     }
#   }
# 
#   
#   body <- gsub("\f", "\\end{verbatim}\n\\newpage\n\\begin{verbatim}", body, fixed = TRUE)
#   body[length(body) + 1] <- "\\end{verbatim}"
#   
#   t1 <- tempfile(tmpdir = tmp_dir, fileext = ".pdf")
#   
#   if (file.exists(rmd_path))
#     file.remove(rmd_path)
# 
#   # Write to file
#   f <- file(rmd_path, open="w+", encoding = "native.enc")
# 
# 
#   writeLines(enc2utf8(hdr), con = f, useBytes = TRUE)
# 
#   writeLines(enc2utf8(body), con = f, useBytes = TRUE)
# 
#   close(f)
#   
#   # There is a known warning on rendering 8pt font.
#   # Can't figure out how to get rid of it.
#   # So going to suppress it for now.
#   # Other fonts sizes shouldn't have any warnings.
#   # if (rs$font_size == 8) {
#   #   suppressWarnings(rmarkdown::render(rmd_path, 
#   #                                      rmarkdown::pdf_document(), t1, 
#   #                                      quiet = TRUE))
#   # } else {
#   #   rmarkdown::render(rmd_path, 
#   #                     rmarkdown::pdf_document(), t1, 
#   #                     quiet = TRUE)
#   # }
#   
#   file.copy(t1, pdf_path)
# 
#   if (file.exists(t1))
#     file.remove(t1)
#   
#   return(ret)
#   
# }