#################################### DicomRDS Class #############################################

#' DicomRDS Class

#'

#' This class is a class that imports various metadata by reading an RDS file containing DICOM information.

#' There are basically functions that import data related to Radiology CDM.

#'

#' @param data Data frame imported from DICOM RDS file

#' @seealso https://github.com/OHDSI/Radiology-CDM/wiki

#' @author Neon K.I.D

#' @example Examples/DicomRDS_Ex.R

#' @export

DicomRDS <- R6::R6Class(classname = "DicomRDS",

  private = list(

    # Parameter name is TagName

    getTagValue = function(name) {

      tryCatch({

        res <- self$data$value[which(ifelse(self$data$name %in% name, TRUE, FALSE))]

        if(is.empty(x = res))

          res <- NA

      }, error = function(e) {

        res <- NA

        assign("res", res, envir = .GlobalEnv)

      })

      return(res)

    },

    isValidTag = function(name) if(is.boolean(which(ifelse(self$data$name %in% name, TRUE, FALSE)) == 0)) TRUE else FALSE,

    getTagLength = function(name) {

      tryCatch({

        len <- as.numeric(self$data$length[which(ifelse(self$data$name %in% name, TRUE, FALSE))])

        if(is.empty(x = len))

          len <- NA

      }, error = function(e) {

        len <- NA

        assign("len", len, envir = .GlobalEnv)

      })

      return(len)

    }

  ),

  public = list(

    data = NULL,

    idp = NULL,

    initialize = function(data, idp = 2) {

      library(stringr)

      self$data = data

      self$idp = idp

    },

    # isContrast for Brain-CT

    isPost4BrainCT = function() {

      tryCatch({

        if(private$isValidTag(name = "ContrastBolusAgent"))

          return(TRUE)

        else if(private$isValidTag(name = "PhotometricInterpretation")) {

          colorVal <- private$getTagValue(name = "PhotometricInterpretation")

          if(pmatch(x = colorVal, "RGB", nomatch = FALSE) == 1)

            return(TRUE)

        }

        if(private$isValidTag(name = "ContrastBolusRoute"))

          return(TRUE)

        else

          return(FALSE)

      }, error = function(e) {

        return(FALSE)

      })

    },

    # Creation Radiology ID

    # createOccurrenceID = function() {

    #   seriesID <- unlist(strsplit(x = private$getTagValue("SeriesInstanceUID"), split = '[.]'))

    #   studyID <- unlist(strsplit(x = private$getTagValue("StudyInstanceUID"), split = '[.]'))

    #

    #   x <- seriesID[length(seriesID)]

    #   y <- as.numeric(

    #     substr(x = studyID[length(studyID)], start = nchar(studyID[length(studyID)]) - 4, stop = nchar(studyID[length(studyID)]))

    #   )

    #

    #   directoryID <- self$getDirectoryID()

    #   i <- directoryID

    #   z <- as.numeric(substr(x = directoryID, start = nchar(directoryID) - 2, stop = nchar(directoryID)))

    #

    #   # Numbering...

    #   if(nchar(x) > 7)

    #     x <- as.numeric(substr(x = x, start = nchar(x) - 5, stop = nchar(x)))

    #   else

    #     x <- as.numeric(x)

    #

    #   max.val <- i + abs(y - nchar(trunc(x)) - x)

    #   count <- nchar(trunc(max.val))

    #

    #   size <- paste("%0", count, "d", sep = "")

    #   set.seed(i)

    #   # lets <- toupper(sample(letters,x, replace = TRUE))

    #   nums <- sprintf(ifelse(length(size) > 1, size[1], size), sample(1:max.val)[1:nchar(trunc(z))])

    #   res <- paste(nums, sep = "")

    #   return(sum(as.numeric(res)))

    # },

    getStudyDate = function() return(private$getTagValue("StudyDate")),

    getStudyTime = function() return(private$getTagValue("StudyTime")),

    # Get Image shot dateTime

    getStudyDateTime = function() {

      studyDate <- private$getTagValue("StudyDate")

      studyTime <- private$getTagValue("StudyTime")

      return(getDateTime(studyDate, studyTime))

    },

    getDuringTime = function(studyDateTime) {

      tryCatch({

        if(private$isValidTag("AcquisitionDate")) {

          acqDate <- private$getTagValue("AcquisitionDate")

          acqTime <- private$getTagValue("AcquisitionTime")

          acqDatetime <- getDateTime(acqDate, acqTime)

          duringTime <- getDiffTime(studyDateTime, acqDatetime)

          return(duringTime)

        }

      }, error = function(e) {

        return(NA)

      })

    },

    getPatientID = function() return(private$getTagValue("PatientID")),

    getDeviceID = function() return(private$getTagValue("DeviceSerialNumber")),

    getModality = function() {

      modal <- private$getTagValue("Modality")

      if(!is.na(modal) && !is.null(modal)) switch(modal, CT = 10321, MR = 10312, OT = 49585)

      else NA

    },

    getOrientation = function() return(private$getTagValue("PatientOrientation")),

    getPosition = function() {

      pos <- private$getTagValue("PatientPosition")

      if(!is.na(pos) && !is.null(pos)) switch(pos, HFS = 10421, pos)

      else NA

    },

    getComment = function() return(private$getTagValue("ImageComments")),

    getDosageunit = function(modality) if(modality == 10312) return("Tesla") else return("kVp"),

    getDosage = function(dosageUnit) {

      sha = private$getTagValue(dosageUnit)

      if(is.empty(sha)) return(NA) else return(sha)

    },

    getSourceID = function() return(private$getTagValue("SOPInstanceUID")),

    getPersonID = function() return(private$getTagValue("PatientID")),

    getStudyID = function() return(private$getTagValue("StudyID")),

    getDirectoryID = function() {

      sp <- strsplit(as.character(self$data$path[length(self$data$path)]), '/')

      shortPath <- tail(x = unlist(sp), -1)

      nVec <- unlist(stringr::str_extract_all(string = shortPath[self$idp], pattern = "\\-*\\d+\\.*\\d*"))

      num <- ifelse(length(nVec) > 1, Reduce(pasteNormal, c(abs(as.numeric(nVec[1])), abs(as.numeric(nVec[2])))), nVec)

      return(as.numeric(num))

    },

    getImageType = function() {

      exType <- private$getTagValue("ImageType")

      if(!is.na(exType)) {

        if(stringr::str_detect(string = exType, pattern = "ORIGINAL"))

          imType <- "PRIMARY"

        else if(is.boolean(str_detect(exType, "DERIVED")))

          imType <- "SECONDARY"

      } else {

        imType <- exType

      }

      return(imType)

    },

    getThickness = function() return(private$getTagValue(name = "SliceThickness")),

    getImgRows = function() return(private$getTagValue(name = "Rows")),

    getImgCols = function() return(private$getTagValue(name = "Columns")),

    getWindowCenter = function() return(private$getTagValue(name = "WindowCenter")),

    getWindowWidth = function() return(private$getTagValue(name = "WindowWidth")),

    isPixelData = function() return(private$getTagLength("PixelData") != -1),

    # free func in C...

    # finalize method in Java...

    finalize = function() {}

  )

)