#' @title Plot a dose-response curve for luminescence data (Lx/Tx against dose)
#'
#' @description
#'
#' A dose-response curve is produced for luminescence measurements using a
#' regenerative or additive protocol as implemented in [Luminescence::fit_DoseResponseCurve].
#'
#' @param object [Luminescence::RLum.Results-class] (**required**):
#' An object produced by [Luminescence::fit_DoseResponseCurve].
#'
#' @param plot_extended [logical] (*with default*):
#' If `TRUE`, 3 plots on one plot area are provided:
#' 1. growth curve,
#' 2. histogram from Monte Carlo error simulation and
#' 3. a test dose response plot.
#'
#' If `FALSE`, just the growth curve will be plotted.
#'
#' @param plot_singlePanels [logical] (*with default*):
#' single plot output (`TRUE/FALSE`) to allow for plotting the results in
#' single plot windows. Ignored if `plot_extended = FALSE`.
#'
#' @param verbose [logical] (*with default*):
#' enable/disable output to the terminal.
#'
#' @param ... Further graphical parameters to be passed (supported:
#' `main`, `mtext`, `xlim`, `ylim`, `xlab`, `ylab`, `log`
#' (not valid for objects fitted with `mode = "extrapolation"`), `legend` (`TRUE/FALSE`),
#' `legend.pos`, `reg_points_pch`, `density_polygon` (`TRUE/FALSE`),
#' `density_polygon_col`, `density_rug` (`TRUE`/`FALSE`),
#' `box` (`TRUE`/`FALSE`).
#'
#' @return
#' A plot (or a series of plots) is produced.
#'
#' @section Function version: 1.0.8
#'
#' @author
#' Sebastian Kreutzer, F2.1 Geophysical Parametrisation/Regionalisation, LIAG - Institute for Applied Geophysics (Germany)\cr
#' Michael Dietze, GFZ Potsdam (Germany) \cr
#' Marco Colombo, Institute of Geography, Heidelberg University (Germany)
#'
#' @references
#'
#' Berger, G.W., Huntley, D.J., 1989. Test data for exponential fits. Ancient TL 7, 43-46.
#'
#' Guralnik, B., Li, B., Jain, M., Chen, R., Paris, R.B., Murray, A.S., Li, S.-H., Pagonis, P.,
#' Herman, F., 2015. Radiation-induced growth and isothermal decay of infrared-stimulated luminescence
#' from feldspar. Radiation Measurements 81, 224-231.
#'
#' Pagonis, V., Kitis, G., Chen, R., 2020. A new analytical equation for the dose response of dosimetric materials,
#' based on the Lambert W function. Journal of Luminescence 225, 117333. \doi{10.1016/j.jlumin.2020.117333}
#'
#' @seealso [Luminescence::fit_DoseResponseCurve]
#'
#' @examples
#'
#' ##(1) plot dose-response curve for a dummy dataset
#' data(ExampleData.LxTxData, envir = environment())
#' fit <- fit_DoseResponseCurve(LxTxData)
#' plot_DoseResponseCurve(fit)
#'
#' ##(1b) horizontal plot arrangement
#' layout(mat = matrix(c(1,1,2,3), ncol = 2))
#' plot_DoseResponseCurve(fit, plot_singlePanels = TRUE)
#'
#' ##(2) plot the dose-response curve with pdf output - uncomment to use
#' ##pdf(file = "~/Dose_Response_Curve_Dummy.pdf", paper = "special")
#' plot_DoseResponseCurve(fit)
#' ##dev.off()
#'
#' ##(3) plot the growth curve with pdf output - uncomment to use, single output
#' ##pdf(file = "~/Dose_Response_Curve_Dummy.pdf", paper = "special")
#' plot_DoseResponseCurve(fit, plot_singlePanels = TRUE)
#' ##dev.off()
#'
#' ##(4) plot resulting function for given interval x
#' x <- seq(1,10000, by = 100)
#' plot(
#'  x = x,
#'  y = eval(fit$Formula),
#'  type = "l"
#' )
#'
#' @export
plot_DoseResponseCurve <- function(
  object,
  plot_extended = TRUE,
  plot_singlePanels = FALSE,
  verbose = TRUE,
  ...
) {
  .set_function_name("plot_DoseResponseCurve")
  on.exit(.unset_function_name(), add = TRUE)

  ## get Luminescence colours
  col <- get("col", pos = .LuminescenceEnv)

  ## Integrity checks -------------------------------------------------------
  .validate_class(object, "RLum.Results")
  .validate_logical_scalar(plot_extended)
  .validate_logical_scalar(plot_singlePanels)
  .validate_logical_scalar(verbose)

  ## Fitting arguments ------------------------------------------------------
  fit.args <- object$Fit.Args
  mode <- fit.args$mode
  sample <- fit.args$object

  ## for interpolation the first point is considered as natural dose
  first.idx <- ifelse(mode == "interpolation", 2, 1)
  last.idx <- fit.args$fit.NumberRegPoints + 1
  xy <- sample[first.idx:last.idx, 1:2]
  colnames(xy) <- c("x", "y")
  y.Error <- sample[first.idx:last.idx, 3]

  De <- object@data$De$.De.plot
  x.natural <- na.exclude(object@data$De.MC)
  De.MonteCarlo <- mean(na.exclude(x.natural))
  De.Error <- sd(na.exclude(x.natural))

  ## Graphical arguments ----------------------------------------------------
  ymax <- max(xy$y) + if (max(xy$y) * 0.1 > 1.5) 1.5 else max(xy$y) * 0.2
  ylim <- if (mode == "extrapolation" || fit.args$fit.force_through_origin) {
            c(0 - max(y.Error), ymax)
          } else {
            c(0, ymax)
          }

  xmin <- if (!is.na(De)) min(De * 2, 0) else -min(xy$x) * 2
  xmax <- max(xy$x) + if (max(xy$x) * 0.4 > 50) 50 else max(xy$x) * 0.4
  xlim <- if (mode == "extrapolation") {
            c(xmin, xmax)
          } else {
            c(0, xmax)
          }

  ## set plot settings
  plot_settings <- modifyList(
    x = list(
      main = "Dose-response curve",
      xlab = "Dose [s]",
      ylab = if (mode == "interpolation") expression(L[x]/T[x]) else "Luminescence [a.u.]",
      ylim = ylim,
      xlim = xlim,
      mar = c(4, 3, 3, 1),
      mgp = c(2, 0.7, 0),
      tcl = -0.4,
      cex = 1,
      mtext = if (mode != "alternate")
                substitute(D[e] == De,
                           list(De = sprintf("%.2f \uB1 %.1e  |  fit: %s",
                                             abs(De), De.Error, fit.args$fit.method)))
              else "",
      log = "",
      legend = TRUE,
      legend.pos = if (mode == "interpolation") "topleft" else "bottomright",
      reg_points_pch = c(19, 1, 2), # point, point 0, point repeated
      density_polygon = TRUE,
      density_polygon_col = rgb(1,0,0,0.2),
      density_rug = TRUE,
      box = TRUE),
    val = list(...),
    keep.null = TRUE
  )

  if (plot_settings$log != "") {
    if (mode == "extrapolation") {
      .throw_message("Logarithmic transformation not allowed on an object ",
                     "fitted with mode = 'extrapolation', 'log' reset to ''")
      plot_settings$log <- ""
    } else {
      ## if we want to apply a log-transform on x and the first time point
      ## is 0, we shift the curves by one channel
      if (grepl("x", plot_settings$log) && min(xy$x) == 0) {
        xy$x[xy$x == 0] <- 1
        plot_settings$xlim[1] <- min(xy$x)
      }
      if (grepl("y", plot_settings$log)) {
        plot_settings$ylim[1] <- min(xy$y)
      }
    }
  }

  if (length(plot_settings$reg_points_pch) < 3) {
    plot_settings$reg_points_pch <- c(19, 1, 2)
    .throw_message("'reg_points_pch' should have length 3 (for point, point 0, ",
                   "point repeated), 'reg_points_pch' reset to c(19, 1, 2)")
  }

  ## Main plots -------------------------------------------------------------

  ## open plot area
  if (plot_extended && !plot_singlePanels) {
    par.default <- .par_defaults()
    graphics::layout(matrix(c(1, 1, 1, 1, 2, 3), 3, 2, byrow = TRUE), respect = TRUE)
    par(cex = 0.8 * plot_settings$cex, mar = c(3, 3, 3, 1))
  } else {
    ## only restore those we are changing, to avoid resetting all graphical
    ## parameters if we were restoring also mfrow/mfcol, as that would affect
    ## the plots generated by analyse_SAR.CWOSL() and analyse_pIRIRSequence()
    par.default <- par(c("cex", "mar", "mgp"))
    par(mar = plot_settings$mar)
  }
  on.exit(par(par.default), add = TRUE)
  par(mgp = plot_settings$mgp, tcl = plot_settings$tcl)

  #PLOT		#Plot input values
  ##Make selection to support manual number of reg points input
  plot_check <- try(plot(
      xy[1:fit.args$fit.NumberRegPointsReal, ],
      ylim = plot_settings$ylim,
      xlim = plot_settings$xlim,
      log = plot_settings$log,
      pch = plot_settings$reg_points_pch[1],
      xlab = plot_settings$xlab,
      ylab = plot_settings$ylab,
      frame.plot = plot_settings$box[1]
  ),
  silent = TRUE)

  ## now that we have opened the plot, we can work out the coordinates of
  ## the extremes, applying a log-transformation if necessary
  par.usr <- par("usr")
  if (grepl("x", plot_settings$log)) par.usr[1:2] <- 10^par.usr[1:2]
  if (grepl("y", plot_settings$log)) par.usr[3:4] <- 10^par.usr[3:4]

  if (!inherits(plot_check, "try-error")) {
    if (mode == "extrapolation") {
      abline(v = 0, lty = 1, col = "grey")
      abline(h = 0, lty = 1, col = "grey")
    }

    ### add header
    title(main = plot_settings$main, line = NA)

    ## add curve
    if (inherits(object$Formula, "expression")) {
      ## make sure that we always have a zero: here we operate with the
      ## original par("usr") values, so that in case of log-transformation
      ## the points are still uniformly spaced (#845)
      x <- sort(c(0, seq(par("usr")[1], par("usr")[2], length.out = 100)))
      if (grepl("x", plot_settings$log))
        x <- 10^x

      lines(x, eval(object$Formula))
    }

    ## natural value
    if (mode == "interpolation") {
      if(!plot_settings$density_polygon[1]) {
        points(
          x = sample[1, 1:2],
          col = 2,
          pch = plot_settings$reg_points_pch[1])
        segments(sample[1, 1], sample[1, 2] - sample[1, 3],
                 sample[1, 1], sample[1, 2] + sample[1, 3], col = col[2])
      }
    } else if (mode == "extrapolation"){
      points(
        x = De,
        y = 0,
        bg = col[2],
        pch = 21,
        col = "black",
        cex = 1.1)
    }

    ## repeated Point
    idx.rep <- which(duplicated(xy[, 1]))
    points(
        x = xy[idx.rep, 1],
        y = xy[idx.rep, 2],
        pch = plot_settings$reg_points_pch[3])

       ## LINES	#Insert Ln/Tn
    if (mode == "interpolation") {
      xmax <- if (is.na(De)) max(sample[, 1]) * 2 else De
      try(lines(
          c(par.usr[1], xmax),
          c(sample[1, 2], sample[1, 2]),
          col = col[2],
          lty = 2,
          lwd = 1.25
      ), silent = TRUE)
      try(lines(
          c(De, De),
          c(par.usr[3], sample[1, 2]),
          col = col[2],
          lty = 2,
          lwd = 1.25), silent = TRUE)
      try({
        points(
          x = De,
          y = sample[1, 2],
          col = "black",
          pch = 21,
          bg = col[2],
          cex = 1.1)
        },
        silent = TRUE)

      if (plot_settings$density_polygon[1] & length(x.natural) > 1 &&
          !all(is.na(x.natural))) {
          ##calculate density De.MC
          density_De <- stats::density(x.natural, na.rm = TRUE)

          ##calculate transformation function
          density_De$y <- .rescale(
            x = density_De$y,
            range_old = c(max(density_De$y), min(density_De$y)),
            range_new = c(sample[1, 2] / 2, par.usr[3]))

          ## for De
          ## we add two extra points to ensure that the base is not wonky (#847)
          polygon(
            x = c(density_De$x, tail(density_De$x, 1), density_De$x[1]),
            y = c(density_De$y, min(density_De$y), min(density_De$y)),
            col = plot_settings$density_polygon_col)

          ## for LxTx
          tmp_y <- seq(
            sample[[2]][1] - 5 * sample[[3]][1],
            sample[[2]][1] + 5 *  sample[[3]][1],
            length.out = 100)

          tmp_x <- dnorm(tmp_y, mean = sample[1, 2], sd = sample[1, 3])

          tmp_x <-  .rescale(
            x = tmp_x,
            range_old = c(max(tmp_x), min(tmp_x)),
            range_new = c(sample[[2]][1], par.usr[1]))

          # draw polygon
          polygon(
            x = tmp_x,
            y = tmp_y,
            col = plot_settings$density_polygon_col)

          rm(tmp_x, tmp_y, density_De)
      }

      ## reg Point 0
      idx.0 <- which(xy == 0)
      points(
        x = xy[idx.0, 1],
        y = xy[idx.0, 2],
        pch = plot_settings$reg_points_pch[2],
        cex = 1.5)

      ## y-error bar
      segments(xy$x, xy$y - y.Error, xy$x, xy$y + y.Error)

      if(plot_settings$density_rug[1])
        suppressWarnings(graphics::rug(x = x.natural, side = 3))

    } else if (mode == "extrapolation" && !is.na(De)) {
        abline(v = De, lty = 2, col = col[2])
        lines(x = c(0,De), y = c(0,0), lty = 2, col = col[2])
    }

    ## insert fit and result
    try(mtext(side = 3,
              plot_settings$mtext,
              cex = 0.8 * par("cex")),
        silent = TRUE)

    ## write error message in plot if De is NaN or NA
    try(if (is.na(De) & mode != "alternate") {
          text(sample[2, 1],
              0,
              "Error: De could not be calculated!",
              adj = c(0, 0),
              cex = 0.8,
              col = col[2]
          )
        }, silent = TRUE)

    ## plot legend
    if(plot_settings$legend) {
      legend(
          plot_settings$legend.pos,
          legend = paste(ifelse(mode == "interpolation", "REG", "Dose"),
                         c("point", "point 0", "point repeated")),
          pch = plot_settings$reg_points_pch,
          cex = 0.7,
          bty = "n")
    }

    if (plot_extended) {
      ## decrease spacing between axis labels and plots
      par(mar = if (plot_singlePanels) c(4, 2, 1.5, 1) else c(4, 3.5, 2.5, 1),
          mgp = c(1.2, 0.4, 0), tcl = -0.3)

      ## Histogram ----------------------------------------------------------
      if (!plot_singlePanels)
        par(cex = 0.7 * plot_settings$cex)

      ## calculate histogram data
      try(histogram <- hist(x.natural, plot = FALSE), silent = TRUE)

      ## to avoid errors plot only if histogram exists
      if (exists("histogram") && length(histogram$counts) > 2) {

        ## plot histogram
        histogram <- try(hist(
            x.natural,
            xlab = plot_settings$xlab,
            ylab = "Freq.",
            main = "MC runs",
            freq = FALSE,
            border = "white",
            axes = FALSE,
            sub = paste0("valid fits = ", length(na.exclude(x.natural)),
                         "/", fit.args$n.MC),
            cex.sub = 0.8,
            cex.lab = 0.8,
            cex.main = 0.8,
            col = "grey"
        ), silent = TRUE)

        ## add axes
        if (!inherits(histogram, "try-error")) {
          axis(side = 1, cex.axis = 0.8)
          axis(side = 2, cex.axis = 0.8,
               at = seq(min(histogram$density),
                        max(histogram$density), length = 5),
               labels = round(
                 seq(
                   min(histogram$counts),
                   max(histogram$counts),
                   length = 5),
                 digits = 0))

          ## add norm curve
          x <- seq(par("usr")[1], par("usr")[2], length.out = 100)
          y_curve <- stats::dnorm(x,
            mean = mean(x.natural, na.rm = TRUE),
            sd = sd(x.natural, na.rm = TRUE))

            ## rescale
            y_curve <- .rescale(
              x = y_curve,
              range_old = range(y_curve),
              range_new = c(0,par()$usr[4]))

          ## plot lines
          lines(x, y_curve, col = col[2], lty = 2)

          ## add rug
          suppressWarnings(graphics::rug(x.natural))

          ## add difference text
          legend('topright',
                 legend = paste0(
                  "diff. ",
                  round(
                    x = abs((abs(De) - De.MonteCarlo) / abs(De) * 100),
                    digits = 1),
                 "%"),
                 cex = 0.7,
                 bty = "n")

          ## De + Error from MC simulation + quality of error estimation
          # De label
          De.label <- paste(
            abs(round(De.MonteCarlo, 2)),
            "\u00B1",
            format(De.Error, scientific = De.Error < 0.01, digits = 2))

          # set expression
          De.expr <- substitute(D[e[MC]] == val, list(val = De.label))

          # Safely add the text to the plot
          try(
            mtext(
              side = 3,
              line = ifelse(plot_singlePanels, -0.45, -0.2),
              text = De.expr,
              cex = 0.7 * par("cex")
            ),
            silent = TRUE)
        }

      } else {
        plot_check <- try(plot(NA, NA, xlim = c(0, 10), ylim = c(0, 10),
                               axes = FALSE, xlab = "", ylab = "",
                               main = expression(paste(D[e], " from MC runs"))),
                          silent = TRUE)
        if (!inherits(plot_check,"try-error"))
          text(5, 5, "Not available", xpd = NA)
      }

      ## Test dose response curve if available ------------------------------
      ## plot Tx/Tn value for sensitivity change
      if (!inherits(plot_check, "try-error")) {
        if ("TnTx" %in% colnames(sample)) {
          plot(
              1:length(sample[, "TnTx"]),
              sample[, "TnTx"] / sample[1, "TnTx"],
              xlab = "#SAR-cycle",
              ylab = expression(paste(T[x] / T[n])),
              main = "Sensitivity",
              cex.lab = 0.8,
              cex.main = 0.8,
              cex.axis = 0.8,
              type = "o",
              xpd = NA,
              pch = 20)
          lines(c(0, nrow(sample) + 1), c(1, 1), lty = 2, col = "gray")
        } else {
          plot(NA, NA, xlim = c(0, 10), ylim = c(0, 10),
               axes = FALSE, xlab = "", ylab = "",
               main = "Sensitivity", cex.main = 0.8)
          text(5, 5, "Not available\nNo TnTx column", xpd = NA)
        }
      }
    }
  }

  ##reset graphic device if the plotting failed!
  if (inherits(plot_check, "try-error")) {
    # nocov start
    .throw_message("Figure margins too large, nothing plotted")
    grDevices::dev.off()
    # nocov end
  }

  ## return
  invisible(object)
}
