# Visualization ----
#' @title Are Colors
#'
#' @description Checks to see if a given vector can be
#' interpreted by R as a color or colors
#'
#' @param col A vector of anything to be interpreted by `rgb`
#' as a color.
#'
#' @return A logical vector stating whether inputs
#' can be interpreted as colors.
#'
#' @examples
#'
#' areColors(col = c("red", "prairie_chicken", 2))
#'
#' @importFrom grDevices col2rgb
#'
#' @keywords internal plotting
#'
#' @export

areColors <- function(col) {
  if(is.null(col)){
    warning(paste0("'col' cannot be NULL.\n"))
    return(NULL)
  } else{
    result <- sapply(col, function(X) {
      tryCatch(is.matrix(col2rgb(X)),
               error = function(e) FALSE)
    })
    return(result)
  }
}

#' @title Test Intersection
#'
#' @description Tests whether two rasters overlap. Used in
#' `\code{\link[voluModel:diversityStack]{diversityStack}}`
#' function to verify all rasters in list overlap with the
#' template raster.
#'
#' @param a The first `SpatRaster` object
#'
#' @param b The second `SpatRaster` object
#'
#' @return A logical vector stating whether the two
#' inputs overlap
#'
#' @examples
#'
#' library(terra)
#' rast1 <- rast(ncol=10, nrow=10)
#' values(rast1) <- rep(0:1, 50)
#'
#' rast2 <- rast(ncol=10, nrow=10)
#' values(rast2) <- c(rep(0, 50), rep(1,50))
#'
#' testIntersection(rast1, rast2)
#'
#' rast1 <- crop(rast1, ext(10, 20, 30, 40))
#' rast2 <- crop(rast2, ext(-20, -10, -40, -30))
#'
#' testIntersection(rast1, rast2)
#'
#' @importFrom grDevices col2rgb
#'
#' @keywords internal plotting
#'
#' @export

testIntersection <- function(a,b){
  #reads in two rasters and tests for overlap T or F
  # if returns TRUE then there is overlap
  # try error is included b/c errors has come up with other test data
  !(inherits(try(intersect(a,b),T ), what ='try-error') || is.null(intersect(a,b)))
}

#' @title Point mapping
#'
#' @description A convenient wrapper around ggplot
#' to generate formatted occurrence point plots.
#'
#' @param occs A `data.frame` with at least two columns
#' named "longitude" and "latitude" or that
#' can be coerced into this format.
#'
#' @param spName A character string with the species
#' name to be used in the plot title.
#'
#' @param land An optional coastline polygon shapefile
#' of types `sf` or `SpatRaster` to provide geographic
#' context for the occurrence points.
#'
#' @param ptCol Color for occurrence points on map
#'
#' @param landCol Color for land on map
#'
#' @param waterCol Color for water on map
#'
#' @param ptSize `numeric` value for `cex`;
#' size of occurrence points on map.
#'
#' @param verbose `logical`. Switching to `FALSE` mutes message describing
#' which columns in `occs` are interpreted as x and y coordinates.
#'
#' @param ... Additional optional arguments to pass to
#' `ggplot` initial plot object.
#'
#' @return A `ggplot` plot object.
#'
#' @examples
#' occs <- read.csv(system.file("extdata/Steindachneria_argentea.csv",
#'                              package='voluModel'))
#' spName <- "Steindachneria argentea"
#' pointMap(occs = occs, spName = spName,
#'          land = rnaturalearth::ne_countries(scale = "small",
#'                                             returnclass = "sf")[1])
#'
#' @import ggplot2
#'
#' @seealso \code{\link[ggplot2:ggplot]{ggplot}}
#'
#' @keywords plotting
#' @export

pointMap <- function(occs, spName, land = NA,
                     ptCol = "#bd0026", landCol = "gray",
                     waterCol = "steelblue", ptSize = 1,
                     verbose = TRUE,
                     ...){
  args <- list(...)

  if("mapping" %in% names(args)){
    mapping <- args$mapping
  } else{
    mapping <- aes()
  }

  if("alpha" %in% names(args)){
    alpha <- args$alpha
  } else{
    alpha <- 2/3
  }

  if (!is.logical(verbose)) {
    warning(message("Argument 'verbose' is not of type 'logical'.\n"))
    return(NULL)
  }

  # Input checking
  if(!is.data.frame(occs)){
    warning(paste0("'occs' must be an object of class 'data.frame'.\n"))
    return(NULL)
  }

  if(!is.character(spName)){
    warning(paste0("'spName' must be an object of class 'character'.\n"))
    return(NULL)
  }

  if(!any(is.na(land[[1]]),
          "sf" %in% class(land),
          "SpatVector" %in% class(land))){
    warning(paste0("'land' must be NA or of class 'sf' or 'SpatVector'."))
    return(NULL)
  }

  if(!any(is.na(land))){
    if(!("sf" %in% class(land))){
      land <- sf::st_as_sf(land)
    }
  }

  colVec <- c(ptCol, landCol, waterCol)
  colTest <- areColors(colVec)

  if(!any(c(all(colTest), length(colTest) < 3))){
    warning(paste0("'ptCol', 'landCol', and 'waterCol' must
                   be recognized colors.\n"))
    return(NULL)
  }

  if(!is.numeric(ptSize)){
    warning(paste0("'ptSize' must be numeric.\n"))
  }

  # Parse columns
  colNames <- colnames(occs)
  colParse <- columnParse(occs)
  if(is.null(colParse)){
    return(NULL)
  }
  xIndex <- colParse$xIndex
  yIndex <- colParse$yIndex
  interp <- colParse$reportMessage

  if(verbose){
    message(interp)
  }

  # Where the actual function happens
  if(any(is.na(land))){
      point_map <- ggplot(mapping = mapping) +
        geom_point(data = occs, aes(x = occs[[xIndex]], y = occs[[yIndex]]),
                   colour = ptCol, cex = ptSize, shape = 20, alpha = alpha) +
        theme(panel.background = element_rect(fill = waterCol),
              panel.grid = element_blank()) +
        coord_sf(xlim = c(min(occs[[xIndex]]), max(occs[[xIndex]])),
                 ylim = c(min(occs[[yIndex]]), max(occs[[yIndex]])),
                 expand = TRUE, ) +
        xlab("") +
        ylab("") +
        ggtitle(paste0(spName, ", ", nrow(occs), " points"))
  }else{
    point_map <- ggplot(mapping = mapping) +
      geom_sf(data = land, color = landCol, fill = landCol) +
      geom_point(data = occs, aes(x = occs[[xIndex]], y = occs[[yIndex]]),
                 colour = ptCol, cex = ptSize, shape = 20, alpha = alpha) +
      theme(panel.background = element_rect(fill = waterCol),
            panel.grid = element_blank()) +
      coord_sf(xlim = c(min(occs[[xIndex]]), max(occs[[xIndex]])),
               ylim = c(min(occs[[yIndex]]), max(occs[[yIndex]])),
               expand = TRUE, ) +
      xlab("") +
      ylab("") +
      ggtitle(paste0(spName, ", ", nrow(occs), " points"))
  }
  return(point_map)
}

#' @title Comparative point mapping
#'
#' @description A convenient wrapper around `ggplot`
#' to generate formatted plots comparing two sets of
#' occurrence point plots.
#'
#' @param occs1 A `data.frame` with at least two columns
#' named "longitude" and "latitude" or that
#' can be coerced into this format.
#'
#' @param occs2 A `data.frame` with at least two columns
#' named "longitude" and "latitude" or that
#' can be coerced into this format.
#'
#' @param spName A character string with the species
#' name to be used in the plot title.
#'
#' @param land An optional coastline polygon shapefile
#' of types `sf` or `SpatRaster` to provide geographic
#' context for the occurrence points.
#'
#' @param occs1Col Color for occurrence points on map
#'
#' @param occs2Col Color for occurrence points on map
#'
#' @param occs1Name An optional name for the first set
#' of occurrences, which will be color-coded to
#' `occs1Col` in the resulting plot.
#'
#' @param occs2Name An optional name for the first set
#' of occurrences, which will be color-coded to
#' `occs2Col` in the resulting plot.
#'
#' @param agreeCol Color for occurrence points shared
#' between `occs1` and `occs2`.
#'
#' @param landCol Color for land on map
#'
#' @param waterCol Color for water on map
#'
#' @param ptSize `numeric` value for `cex`;
#' size of occurrence points on map.
#'
#' @param verbose `logical`. Switching to `FALSE` mutes message describing
#' which columns in `occs1` and `occs2` are interpreted as x and y coordinates.
#'
#' @param ... Additional optional arguments to pass to
#' `ggplot` initial plot object.
#'
#' @return A `ggplot` plot object.
#'
#' @note The x and y column names of `occs1` and `occs2`
#' must match.
#'
#' @examples
#' set.seed(5)
#' occs <- data.frame(cbind(decimalLatitude = sample(seq(7,35), 24),
#'                          decimalLongitude = sample(seq(-97, -70), 24)))
#'
#' set.seed(0)
#' occs1 <- occs[sample(1:nrow(occs),
#'                      size = 12, replace = FALSE),]
#' set.seed(10)
#' occs2 <- occs[sample(1:nrow(occs),
#'                      size = 12, replace = FALSE),]
#'
#' pointCompMap(occs1 = occs1, occs2 = occs2,
#'              occs1Col = "red", occs2Col = "orange",
#'              agreeCol = "purple",
#'              occs1Name = "2D",
#'              occs2Name = "3D",
#'              waterCol = "steelblue",
#'              spName = "Steindachneria argentea",
#'              ptSize = 2,
#'              verbose = FALSE)
#'
#' @import ggplot2
#' @importFrom dplyr inner_join anti_join %>% mutate
#' @importFrom ggtext element_markdown
#'
#' @seealso \code{\link[ggplot2:ggplot]{ggplot}}
#'
#' @keywords plotting
#' @export

pointCompMap <- function(occs1, occs2,
                         spName, land = NA,
                         occs1Col = "#bd0026",
                         occs2Col = "#fd8d3c",
                         agreeCol = "black",
                         occs1Name = "Set 1",
                         occs2Name = "Set 2",
                         landCol = "gray",
                         waterCol = "steelblue",
                         ptSize = 1,
                         verbose = TRUE,
                         ...){
  args <- list(...)

  if("mapping" %in% names(args)){
    mapping <- args$mapping
  } else{
    mapping <- aes()
  }

  # Input checking
  if(!is.data.frame(occs1)){
    warning(paste0("'occs1' must be an object of class 'data.frame'.\n"))
    return(NULL)
  }

  if(!is.data.frame(occs2)){
    warning(paste0("'occs2' must be an object of class 'data.frame'.\n"))
    return(NULL)
  }

  if(!all(c(is.character(spName),
            is.character(occs1Name),
            is.character(occs2Name)))){
    warning(paste0("'spName', 'occs1Name', and 'occs2Name'
                   must be 'character' strings.\n"))
    return(NULL)
  }

  if(!any(is.na(land[[1]]),
          "sf" %in% class(land),
          "SpatVector" %in% class(land))){
    warning(paste0("'land' must be NA or of class 'sf' or 'SpatVector'."))
    return(NULL)
  }

  if(!any(is.na(land))){
    if(!("sf" %in% class(land))){
      land <- sf::st_as_sf(land)
    }
  }

  if (!is.logical(verbose)) {
    warning(message("Argument 'verbose' is not of type 'logical'.\n"))
    return(NULL)
  }

  colVec <- c(occs1Col, occs2Col, agreeCol, landCol, waterCol)
  colTest <- areColors(colVec)

  if(!any(c(all(colTest), length(colTest) < 5))){
    warning(paste0("'pt1Col', 'pt2Col', 'agreeCol', 'landCol',
                    and 'waterCol' must be recognized colors.\n"))
    return(NULL)
  }

  if(!is.numeric(ptSize)){
    warning(paste0("'ptSize' must be numeric.\n"))
    return(NULL)
  }

  # Parse columns
  colNames1 <- colnames(occs1)
  colParse1 <- columnParse(occs1)
  if(is.null(colParse1)){
    return(NULL)
  }
  xIndex1 <- colParse1$xIndex
  yIndex1 <- colParse1$yIndex
  interp1 <- colParse1$reportMessage

  if(verbose){
    message(paste("First set of occurrences: ", interp1))
  }

  colNames2 <- colnames(occs2)
  colParse2 <- columnParse(occs2)
  if(is.null(colParse2)){
    return(NULL)
  }
  xIndex2 <- colParse2$xIndex
  yIndex2 <- colParse2$yIndex
  interp2 <- colParse2$reportMessage

  if(verbose){
    message(paste("Second set of occurrences: ", interp2))
  }

  if(!all(c(colnames(occs1)[[xIndex1]] == colnames(occs2)[[xIndex2]],
           colnames(occs1)[[yIndex1]] == colnames(occs2)[[yIndex2]]))){
    warning(paste0("x and y column names in the two occurrence datasets
                   do not match.\n"))
    return(NULL)
  }

  # Where the function actually starts
  occsBoth <- NA
  occsBoth <- suppressMessages(dplyr::inner_join(occs2[,c(xIndex2, yIndex2)],
                                occs1[,c(xIndex1, yIndex1)], multiple = "all") %>%
    dplyr::distinct() %>%
    dplyr::mutate(source = "both"))
  occs1 <- suppressMessages(dplyr::anti_join(occs1[,c(xIndex1, yIndex1)],occsBoth) %>%
    dplyr::distinct() %>%
    dplyr::mutate(source = occs1Name))
  occs2 <- suppressMessages(dplyr::anti_join(occs2[,c(xIndex2, yIndex2)],occsBoth) %>%
    dplyr::distinct() %>%
    dplyr::mutate(source = occs2Name))

  colParse1 <- columnParse(occs1)
  xIndex1 <- colParse1$xIndex
  yIndex1 <- colParse1$yIndex

  colParse2 <- columnParse(occs2)
  xIndex2 <- colParse2$xIndex
  yIndex2 <- colParse2$yIndex

  if(nrow(occs2)==0) {
    occs1 <- unique(occs1[,c(xIndex1, yIndex1)])
    occs1$source <- rep_len(occs1Name, length.out = nrow(occs1))
  }
  if (nrow(occs1)==0){
    occs2 <- unique(occs2[,c(xIndex2, yIndex2)])
    occs2$source <- rep_len(occs2Name, length.out = nrow(occs2))
  }

  allDat <- list(occsBoth[,c(colnames(occs1)[c(xIndex1,yIndex1)], "source")],
                 occs1[,c(colnames(occs1)[c(xIndex1,yIndex1)], "source")],
                 occs2[,c(colnames(occs2)[c(xIndex2,yIndex2)], "source")])
  occ_dat <- do.call("rbind", allDat[!is.na(allDat)])

  # Now add the occurrence points
  cols <- NULL
  for (x in occ_dat$source){
    if (x == occs1Name){
      cols <- c(cols, occs1Col)
    } else if (x == occs2Name){
      cols <- c(cols, occs2Col)
    } else{
      cols <- c(cols, agreeCol)
    }
  }

  occ_datIndices <- columnParse(occ_dat)

  if(any(is.na(land))){
    comparison_map <- ggplot() +
    geom_point(data = occ_dat, aes(x = occ_dat[[occ_datIndices$xIndex]],
                                   y = occ_dat[[occ_datIndices$yIndex]]),
               colour = cols, cex = ptSize, shape = 20, alpha = 1) +
    theme(panel.background = element_rect(fill = waterCol)) +
    theme(panel.grid = element_blank()) +
    coord_sf(xlim = c(min(occ_dat[[occ_datIndices$xIndex]]),
                      max(occ_dat[[occ_datIndices$xIndex]])),
             ylim = c(min(occ_dat[[occ_datIndices$yIndex]]),
                      max(occ_dat[[occ_datIndices$yIndex]])),
             expand = TRUE, ) +
    xlab("") +
    ylab("") +
    labs(
      title = paste0("***", spName, "***<br>",
                     "<span style='color:", agreeCol, ";'>Overlapping</span>, ",
                     "<span style='color:", occs1Col, ";'>in ", occs1Name,
                     " dataset only</span>, and ",
                     "<span style='color:", occs2Col, ";'>in ", occs2Name,
                     " dataset only</span>")) +
    theme(plot.title = element_markdown(lineheight = .4))}
  else{
    comparison_map <- ggplot() +
      geom_sf(data = land, color = landCol, fill = landCol) +
      geom_point(data = occ_dat, aes(x = occ_dat[[occ_datIndices$xIndex]],
                                     y = occ_dat[[occ_datIndices$yIndex]]),
                 colour = cols, cex = ptSize, shape = 20, alpha = 1) +
      theme(panel.background = element_rect(fill = waterCol)) +
      theme(panel.grid = element_blank()) +
      coord_sf(xlim = c(min(occ_dat[[occ_datIndices$xIndex]]),
                        max(occ_dat[[occ_datIndices$xIndex]])),
               ylim = c(min(occ_dat[[occ_datIndices$yIndex]]),
                        max(occ_dat[[occ_datIndices$yIndex]])),
               expand = TRUE, ) +
      xlab("") +
      ylab("") +
      labs(title = paste0("***", spName, "***<br>",
                          "<span style='color:", agreeCol, ";'>Overlapping</span>, ",
                          "<span style='color:", occs1Col, ";'>in ", occs1Name,
                          " dataset only</span>, and ",
                          "<span style='color:", occs2Col, ";'>in ", occs2Name,
                          " dataset only</span>")) +
      theme(plot.title = element_markdown(lineheight = .4))
  }
  return(comparison_map)
}

#' @title Transparent Color
#'
#' @description Generates transparent colors
#'
#' @param color Anything that can be interpreted by `rgb`
#' as a color.
#'
#' @param percent A whole number between 0 and 100 specifying
#' how transparent the color should be.
#'
#' @return A `character` string with hex color, including
#' adjustment for transparency.
#'
#' @examples
#'
#' transpColor(color = "red", percent = 50)
#'
#' @importFrom grDevices rgb
#'
#' @keywords internal plotting
#'
#' @export

transpColor <- function(color, percent = 50) {
  colTest <- areColors(color)

  if(!colTest){
    warning(paste0("'color' must be a recognized color.\n"))
    return(NULL)
  }

  if(!is.numeric(percent)){
    warning(paste0("'percent' must be numeric.\n"))
    return(NULL)
  }

  if(!all(percent >= 0, 100 >= percent)){
    warning(paste0("'percent' must be between 0 and 100.\n"))
    return(NULL)
  }

  ## Get RGB values for named color
  rgb.val <- col2rgb(color)

  ## Make new color using input color as base and transparency set by alpha
  t.col <- rgb(rgb.val[1], rgb.val[2], rgb.val[3],
               maxColorValue = 255,
               alpha = (100 - percent) * 255 / 100)

  ## Save the color
  return(t.col)
}

#' @title Blend Colors
#'
#' @description Generates a blended color from two transparent colors
#'
#' @param col1 Anything that can be interpreted by `rgb`
#' as a color.
#'
#' @param col2 Anything that can be interpreted by `rgb`
#' as a color.
#'
#' @return A `character` string with hex color, including
#' adjustment for transparency.
#'
#' @examples
#'
#' blendColor(col1 = "#1B9E777F", col2 = "#7570B37F")
#'
#' @importFrom grDevices rgb
#'
#' @keywords internal plotting
#'
#' @export

blendColor <- function( col1 = "#1b9e777F", col2 = "#7570b37F") {
  colVec <- c(col1, col2)
  colTest <- areColors(colVec)

  if(!any(c(all(colTest), length(colTest) < 2))){
    warning(paste0("'col1' and 'col2'
                   must be recognized colors.\n"))
    return(NULL)
  }

  ## Get RGB values for colors
  rgb.val1 <- col2rgb(col1, alpha = TRUE)
  rgb.val2 <- col2rgb(col2, alpha = TRUE)
  alphaVal <- rgb.val1["alpha",] + rgb.val2["alpha",]
  if(alphaVal >= 255){alphaVal <- 255}
  ## Make new color using input color as base and transparency set by alpha
  t.col <- rgb(red = mean(c(rgb.val1["red",], rgb.val2["red",])),
               green = mean(c(rgb.val1["green",], rgb.val2["green",])),
               blue = mean(c(rgb.val1["blue",], rgb.val2["blue",])),
               alpha = alphaVal,
               maxColorValue = 255)

  ## Save the color
  return(t.col)
}

#' @title Comparative raster mapping
#'
#' @description A convenient wrapper around `terra::plot`
#' to generate formatted plots comparing two rasters.
#' This is used in the context of voluModel to
#' overlay semi-transparent distributions (coded as 1)
#' in two different `RasterLayers`.
#'
#' @param rast1 A single `SpatRaster` showing the
#' distribution of the species corresponding to
#' `rast1Name`. Should have values of 0 (absence)
#' and 1 (presence). Can also be `NULL`.
#'
#' @param rast2 A single `SpatRaster` showing the
#' distribution of the species corresponding to
#' `rast2Name`. Should have values of 0 (absence)
#' and 1 (presence). Must match the extent and
#' resolution of `rast1`. Can also be `NULL.`
#'
#' @param col1 Color for `rast1` presences
#'
#' @param col2 Color for `rast2` presences
#'
#' @param rast1Name An optional name for the first set
#' of occurrences, which will be color-coded to
#' `occs1Col` in the resulting plot.
#'
#' @param rast2Name An optional name for the first set
#' of occurrences, which will be color-coded to
#' `occs2Col` in the resulting plot.
#'
#' @param landCol Color for land on map.
#'
#' @param land An optional coastline polygon shapefile
#' of types `sf` or `SpatRaster` to provide geographic
#' context for the occurrence points.
#'
#' @param title A title for the plot.
#'
#' @param graticule Do you want a grid of lon/lat lines?
#'
#' @param ... Additional optional arguments to pass to
#' `terra::plot()`.
#'
#' @return A plot of class `recordedplot` overlaying mapped,
#' semitransparent extents of the input rasters
#'
#' @note The extents of `rast1` and `rast2`
#' must match.
#'
#' @examples
#' library(terra)
#' rast1 <- rast(ncol=10, nrow=10)
#' values(rast1) <- rep(0:1, 50)
#'
#' rast2 <- rast(ncol=10, nrow=10)
#' values(rast2) <- c(rep(0, 50), rep(1,50))
#'
#' rasterComp(rast1 = rast1, rast2 = rast2)
#'
#' @import terra
#' @importFrom grDevices recordPlot
#' @importFrom graphics legend
#'
#' @seealso \code{\link[terra:plot]{plot}}
#'
#' @keywords plotting
#' @export

rasterComp <- function(rast1 = NULL, rast2 = NULL,
                       col1 = "#1b9e777F", col2 = "#7570b37F",
                       rast1Name = "Set 1", rast2Name = "Set 2",
                       land = NA, landCol = "black",
                       title = "A Raster Comparison",
                       graticule = TRUE, ...){

  args <- list(...)

  colVec <- c(col1, col2, landCol)
  colTest <- areColors(colVec)

  if(!any(c(all(colTest), length(colTest) < 3))){
    warning(paste0("'col1', 'col2', and 'landCol'
                   must be recognized colors.\n"))
    return(NULL)
  }

  if(!any(is.na(land[[1]]),
          "sf" %in% class(land),
          "SpatVector" %in% class(land))){
    warning(paste0("'land' must be NA or of class 'sf' or 'SpatVector'."))
    return(NULL)
  }

  if(!all(c(is.character(rast1Name),
            is.character(rast2Name),
            is.character(title)))){
    warning(paste0("'rast1Name', 'rast2Name', and 'title'
                   must be 'character' strings.\n"))
    return(NULL)
  }

  if(!is.logical(graticule)){
    warning(paste0("'graticule' must be 'TRUE' or 'FALSE'.\n"))
    return(NULL)
  }


  if(any(all(!inherits(rast1, what = "SpatRaster"), !is.null(rast1)),
         all(!inherits(rast2, what = "SpatRaster"), !is.null(rast2)))){
    warning(paste0("'rast1' and 'rast2', must either be objects of type
                   'SpatRaster' or NULL.\n"))
    return(NULL)
  }

  if(any(is.null(rast1), is.null(rast2))){
    if(all(is.null(rast1),!is.null(rast2))){
      rast1 <- rast2
      values(rast1) <- 0
      message(paste0("'rast1' was null. Replaced with blank raster."))
    }else if(all(is.null(rast2),!is.null(rast1))){
      rast2 <- rast1
      values(rast2) <- 0
      message(paste0("'rast2' was null. Replaced with blank raster."))
    } else{
      rast1 <- rast(ncol=10, nrow=10)
      values(rast1) <- 0
      rast2 <- rast(ncol=10, nrow=10)
      values(rast2) <- 0
      message(paste0("Both 'rast1' and 'rast2' were null.\n",
                     "They were replaced with blank rasters."))
    }
  }

  # Here is where the function actually starts
  myCols <- c(transpColor("white", percent = 100),
              transpColor(col1, percent = 50),
              transpColor(col2, percent = 50),
              blendColor(transpColor(col1, percent = 50),
                         transpColor(col2, percent = 50)))

  plot(rast1, col = c(myCols[1], myCols[2]), legend = FALSE, axes = TRUE, mar = c(2,2,3,2))
  plot(rast2, col = c(myCols[1], myCols[3]), legend = FALSE, axes = FALSE, add = T)

  if(graticule){
    grat <- graticule(lon = seq(-180, 180, 10), lat = seq(-90,90,10), crs = crs(rast1))
    plot(crop(grat, rast1), col="gray50", labels = FALSE, add = TRUE)
  }

  if(!any(is.na(land))){
    if(!("SpatVector" %in% class(land))){
      land <- vect(land)
    }
    plot(land, col = landCol, add = TRUE)
  }

  title(main = title, cex.main = 1.1)

  # Legend plotting
  if(sum(terra::minmax(rast1), terra::minmax(rast2)) == 0){
    legend(x = round(xmax(rast1)) + 1, y = round(ymax(rast1)) + 1,
           bty = "n",
           legend = c("Neither"),
           fill = myCols[1])
  }else if(terra::minmax(rast1)[2] == 0){
    legend(x = round(xmax(rast1)) + 1, y = round(ymax(rast1)) + 1,
           bty = "n",
           legend = c("Neither", rast2Name),
           fill = myCols[c(-2, -4)])
  }else if(terra::minmax(rast2)[2] == 0){
    legend(x = round(xmax(rast1)) + 1, y = round(ymax(rast1)) + 1,
           bty = "n",
           legend = c("Neither", rast1Name),
           fill = myCols[c(-3, -4)])
  } else{
    legend(x = round(xmax(rast1)) + 1, y = round(ymax(rast1)) + 1,
           bty = "n",
           legend = c("Neither", rast1Name, rast2Name, "Both"),
           fill = myCols)
  }

  plotResult <- recordPlot()
  return(plotResult)
}

#' @title Diversity stack
#'
#' @description Takes list of rasters of species distributions
#' (interpreted as 1 = presence, 0 = absence), which do not
#' have to have the same extents, and stack them to create an
#' estimate of species richness that matches the extent and
#' resolution of a template.
#'
#' @param rasterList A `list` of `SpatRaster` objects, which
#' are interpreted as species distributions (1 = presence,
#' 0 = absence).
#'
#' @param template A `SpatRaster` with the desired extent
#'
#' @return A `SpatRaster`
#'
#' @examples
#' library(terra)
#' rast1 <- rast(ncol=10, nrow=10)
#' values(rast1) <- rep(0:1, 50)
#'
#' rast2 <- rast(ncol=10, nrow=10)
#' values(rast2) <- c(rep(0, 50), rep(1,50))
#'
#' rastList <- list(rast1, rast2)
#' result <- diversityStack(rasterList = rastList,
#'                          template = rast2)
#' result
#' plot(result)
#'
#' @importFrom terra rast resample
#' @keywords plotting
#' @export

diversityStack <- function(rasterList, template){
  if(!inherits(rasterList, what = "list")){
    warning(paste0("'rasterList' must be of class 'list'.\n"))
    return(NULL)
  }

  if(!all(unlist(lapply(rasterList,
                        function(X){grepl("SpatRaster", class(X))})))){
    warning(paste0("All objects in 'rasterList' must be of class 'SpatRaster'.\n"))
    return(NULL)
  }

  if(!grepl("SpatRaster", class(template))){
    warning(paste0("'template' must be of class 'SpatRaster'.\n"))
    return(NULL)
  }

  diversityRaster <- template
  values(diversityRaster) <- 0

  for(i in rasterList){
    temp <- i
    if(testIntersection(temp,template)){
      temp <- terra::resample(temp, template, method = "near")
      temp <- subst(temp, NA, 0)
      diversityRaster <- diversityRaster + temp
    }
  }
  return(diversityRaster)
}

#' @title Single raster plot
#'
#' @description A convenient wrapper around `ggplot`
#' to generate a formatted plot of a single raster.
#'
#' @param rast A single `SpatRaster` layer on a continuous
#' scale.
#'
#' @param land An optional coastline polygon shapefile
#' of types `sf` or `SpatRaster` to provide geographic
#' context for the occurrence points.
#'
#' @param landCol Color for land on map.
#'
#' @param scaleRange Optional numeric vector containing
#' maximum and minimum values for color scale. Helpful
#' when making multiple plots for comparison. Defaults
#' to minimum and maximum of input `rast`.
#'
#' @param title A title for the plot.
#'
#' @param verbose `logical`. Switching to `FALSE` mutes message alerting
#' user if input `rast` values exceed a specified `scaleRange`.
#'
#' @param graticule `logical`. Do you want a grid of lon/lat lines?
#'
#' @param ... Additional optional arguments to pass to
#' `plot` initial plot object or `viridis`.
#'
#' @return A plot of mapping the values of the input raster layer
#'
#' @examples
#' library(terra)
#' rast <- rast(ncol=10, nrow=10)
#' values(rast) <- seq(0,99, 1)
#'
#' oneRasterPlot(rast = rast)
#'
#' @import terra
#' @importFrom viridisLite viridis
#'
#' @seealso \code{\link[viridisLite:viridis]{viridis}} \code{\link[ggplot2:ggplot]{ggplot}}
#'
#' @keywords plotting
#' @export

oneRasterPlot <- function(rast,
                          land = NA, landCol = "black",
                          scaleRange = NA,
                          graticule = TRUE,
                          title = "A Raster",
                          verbose = TRUE, ...){
  #Input processing
  args <- list(...)

  if("alpha" %in% names(args)){
    alpha <- args$alpha
  } else{
    alpha <- 1
  }

  if("option" %in% names(args)){
    option <- args$option
  } else{
    option <- "plasma"
  }

  if("plotLegend" %in% names(args)){
    plotLegend <- args$plotLegend
  } else{
    plotLegend <- FALSE
  }

  if("legendMargin" %in% names(args)){
    legendMargin <- args$legendMargin
  } else{
    legendMargin <- 3
  }

  if("n" %in% names(args)){
    n <- args$n
  } else{
    n = 11
  }

  if("varName" %in% names(args)){
    varName <- args$varName
  } else{
    varName <- "Variable"
  }

  if("legendRound" %in% names(args)){
    legendRound <- args$legendRound
  } else{
    legendRound <- 2
  }

  # Input error checking
  if(!grepl("SpatRaster", class(rast))){
    warning(paste0("'rast' must be of class 'SpatRaster'.\n"))
    return(NULL)
  }

  if(!any(is.na(land[[1]]),
          "sf" %in% class(land),
          "SpatVector" %in% class(land))){
    warning(paste0("'land' must be NA or of class 'sf' or 'SpatVector'."))
    return(NULL)
  }

  if(!any(is.na(land))){
    if(!("sf" %in% class(land))){
      land <- sf::st_as_sf(land)
    }
  }

  if(!all(is.na(scaleRange))){
    if(!all(any("numeric" %in% class(scaleRange)),
            length(scaleRange) == 2)){
      warning(paste0("'scaleRange' must either be NA or\na numeric vector of length 2."))
      return(NULL)
    }
  }

  if (!is.logical(graticule)) {
    warning(message("Argument 'graticule' is not of type 'logical'.\n"))
    return(NULL)
  }

  colTest <- areColors(landCol)

  if(!any(c(all(colTest), length(colTest) < 1))){
    warning(paste0("'landCol' must be a recognized color.\n"))
    return(NULL)
  }

  if (!is.logical(verbose)) {
    warning(message("Argument 'verbose' is not of type 'logical'.\n"))
    return(NULL)
  }

  #Function body
  if(any(is.na(scaleRange))){
    begin <- unlist(global(rast, min, na.rm = TRUE))
    end <- unlist(global(rast, max, na.rm = TRUE))
  } else if(any(global(rast, min, na.rm = TRUE) < min(scaleRange),
                global(rast, max, na.rm = TRUE) > max(scaleRange))){
    begin <- unlist(global(rast, min, na.rm = TRUE))
    end <- unlist(global(rast, max, na.rm = TRUE))

    if(verbose){
      message(paste0("Input raster extremes exceed specified scale range.\n",
                     "Using input raster max and min instead."))
    }

  } else{
    begin <- min(scaleRange)
    end <- max(scaleRange)
  }

  colVals <- seq(from = begin, to = end, by = (end-begin)/n)
  colVals <- round(colVals, legendRound)
  colVals <- data.frame("from" = colVals[1:(length(colVals)-1)],
                        "to" = colVals[2:length(colVals)],
                        "color" = viridisLite::viridis(n = length(colVals)-1, alpha = 1, option = option))

  if(is.na(title)){
    adjustedMargin <- c(2,2,0,2)
  } else{
    adjustedMargin <- c(2,2,3,2)
  }

  if(plotLegend){
    adjustedMargin[[4]] <- legendMargin
  }

  plot(rast,
       col = colVals,
       legend = plotLegend, mar = adjustedMargin,
       axes = TRUE)

  if(graticule){
    grat <- graticule(lon = seq(-180, 180, 10), lat = seq(-90,90,10), crs = crs(rast))
    plot(grat, col="gray50", labels = FALSE, add = TRUE)
  }

  if(!any(is.na(land))){
    if(!("SpatVector" %in% class(land))){
      land <- vect(land)
    }
    plot(land, col = landCol, add = TRUE)
  }

  if(plotLegend){
    legend(x = round(xmax(rast)) + 1,
           yjust = 0,
           title = varName,
           bty = "n",
           legend = paste0(round(colVals[,1], legendRound),
                           " - ", round(colVals[,2], legendRound)),
           fill = colVals[,3])
  }

  if(!is.na(title)){
    title(main = title, cex.main = 1.1)
  }

  finalPlot <- recordPlot()

  return(finalPlot)
}

#' @title Plotting 3D model in 2D
#'
#' @description This script plots a semitransparent layer
#' of suitable habitat for each depth layer. The redder
#' the color, the shallower the layer, the bluer, the
#' deeper. The more saturated the color, the more layers
#' with suitable habitat.
#'
#' @param rast A `SpatRaster` vector with the 3D presence/absence
#' distribution of a species (interpreted as 1 = presence,
#' 0 = absence).
#'
#' @param land An optional coastline polygon shapefile
#' of types `sf` or `SpatRaster` to provide geographic
#' context for the occurrence points.
#'
#' @param landCol Color for land on map.
#'
#' @param title A title for the plot. If not title is
#' supplied, the title "Suitability from (MINIMUM
#' DEPTH) to (MAXIMUM DEPTH)" is inferred from
#' names of `rast`.
#'
#' @param graticule Do you want a grid of lon/lat lines?
#'
#' @param ... Additional optional arguments.
#'
#' @note Only include the depth layers that you actually
#' want to plot.
#'
#' @examples
#' library(terra)
#'
#' rast1 <- rast(ncol=10, nrow=10)
#' values(rast1) <- rep(0:1, 50)
#'
#' rast2 <- rast(ncol=10, nrow=10)
#' values(rast2) <- c(rep(0, 50), rep(1,50))
#'
#' rast3 <- rast(ncol=10, nrow=10)
#' values(rast3) <- rep(c(1,0,0,1), 25)
#'
#' distBrick <- c(rast1, rast2, rast3)
#'
#' plotLayers(distBrick)
#'
#' @import terra
#' @importFrom grDevices recordPlot
#'
#' @seealso \code{\link[viridisLite:viridis]{viridis}}
#'
#' @keywords plotting
#'
#' @return A plot of class `recordedplot`
#'
#' @export

plotLayers <- function(rast,
                      land = NA, landCol = "black",
                      title = NULL,
                      graticule = TRUE, ...){
  #Input processing
  args <- list(...)

  # Input error checking
  if(!grepl("SpatRaster", class(rast))){
    warning(paste0("'rast' must be of class 'SpatRaster'.\n"))
    return(NULL)
  }

  if(!any(is.na(land[[1]]),
          "sf" %in% class(land),
          "SpatVector" %in% class(land))){
    warning(paste0("'land' must be NA or of class 'sf' or 'SpatVector'."))
    return(NULL)
  }

  colTest <- areColors(landCol)

  if(!any(c(all(colTest), length(colTest) < 1))){
    warning(paste0("'landCol' must be a recognized color.\n"))
    return(NULL)
  }

  if (!is.logical(graticule)) {
    warning(message("Argument 'graticule' is not of type 'logical'.\n"))
    return(NULL)
  }

  if(is.null(title)){
   title <- paste0("Suitability from ",
           names(rast)[[1]]," to ",
           names(rast)[[nlyr(rast)]])
  }


  #Function body
  redVal <- 1
  blueVal <- 0
  stepSize <- 1/(nlyr(rast) + 1)

  plot(rast[[1]],
       col = c(rgb(0,0,0,0),
               rgb(redVal,0,blueVal,stepSize)),
       legend = FALSE, mar = c(2,2,3,2), axes = TRUE)

  for(i in 2:nlyr(rast)){
    redVal <- redVal - stepSize
    blueVal <- blueVal + stepSize
    plot(rast[[i]], col = c(rgb(0,0,0,0),
                            rgb(redVal,0,blueVal,stepSize)),
         legend = FALSE, axes = FALSE, add = TRUE)
  }

  if(graticule){
    grat <- graticule(lon = seq(-180, 180, 10), lat = seq(-90,90,10), crs = crs(rast))
    plot(grat, col="gray50", labels = FALSE, add = TRUE)
  }

  if(!any(is.na(land))){
    if(!("SpatVector" %in% class(land))){
      land <- vect(land)
    }
    plot(land, col = landCol, add = TRUE)
  }

  title(main = title, cex.main = 1.1)

  finalPlot <- recordPlot()

  return(finalPlot)
}

#' @title Vertical sample
#'
#' @description Samples data along a vertical transect
#'
#' @param x A multilayer `SpatRaster` object
#'
#' @param sampleAxis Specifies whether a latitudinal ("lat") or
#' longitudinal ("long") transect is desired.
#'
#' @param axisValue Numeric value specifying transect postion.
#'
#' @note Only unprojected `SpatRaster` files are supported.
#'
#' @return A `data.frame` with values sampled across vertical
#' transect.
#'
#' @keywords internal plotting
#'
#' @export

verticalSample <- function(x = NULL, sampleAxis = "lon", axisValue = NA){

  # Input error checking
  if(any(!grepl("SpatRaster", class(x)), is.null(x))){
    warning(paste0("'x' must be of class 'SpatRaster'.\n"))
    return(NULL)
  }

  if(all(!is.numeric(axisValue), !is.na(axisValue))){
    warning(paste0("'axisValue' must be single numeric value."))
    return(NULL)
  }

  if(!(sampleAxis %in% c("lat", "lon"))){
    warning(paste0("'sampleAxis' must be 'lon' or 'lat'."))
    return(NULL)
  }

  samplePoints <- as.data.frame(x, xy = TRUE, na.rm=FALSE)

  # Takes mean axis value if none specified
  if(is.na(axisValue)){
    if(sampleAxis == "lon"){
      axisValue <-  mean(c(xmin(x), xmax(x)))
    } else{
      axisValue <-  mean(c(ymin(x), ymax(x)))
    }
  }

  if(sampleAxis == "lon"){
    if(all(axisValue > xmin(x), axisValue < xmax(x))){
      axisValue <- samplePoints[which.min(abs(samplePoints[,"x"] - axisValue)), "x"]
    } else{
      warning(paste0("'axisValue' falls outside the extent of 'x'."))
      return(NULL)
    }
  } else{
    if(all(axisValue > ymin(x), axisValue < ymax(x))){
      axisValue <- samplePoints[which.min(abs(samplePoints[,"y"] - axisValue)), "y"]
    } else{
      warning(paste0("'axisValue' falls outside the extent of 'x'."))
      return(NULL)
    }
  }

  # Select coordinates to sample
  if(sampleAxis == "lon"){
    samplePoints <- samplePoints[samplePoints[,"x"] == axisValue,]
  } else{
    samplePoints <- samplePoints[samplePoints[,"y"] == axisValue,]
  }

  samplePoints <- lapply(1:nrow(samplePoints), FUN = function(x){
    cbind(rep(samplePoints[x,"x"], n = (ncol(samplePoints)-2)),
          rep(samplePoints[x,"y"], n = (ncol(samplePoints)-2)),
          as.numeric(colnames(samplePoints[c(-1,-2)])),
          t(samplePoints[x,])[c(-1,-2),])
  })

  samplePoints <- as.data.frame(do.call(rbind, samplePoints))
  colnames(samplePoints) <- c("x", "y", "z", "value")

  if(all(is.na(samplePoints$z))){
    samplePoints <- samplePoints[, !names(samplePoints) == "z"]
  } else{
    zVals <- sort(unique(samplePoints$z))
    zHeights <- vector(mode = "numeric",
                       length = length(zVals))
    for(i in 1:length(zHeights)){
      if ( i == length(zHeights)){
        zHeights[[i]] <- abs(zVals[[i]] - zVals[[i-1]])
      } else{
        zHeights[[i]] <- abs(zVals[[i]] - zVals[[i+1]])
      }
    }

    height <- vector(mode = "numeric", length = nrow(samplePoints))
    for(i in 1:nrow(samplePoints)){
      height[[i]] <- zHeights[which(zVals %in% samplePoints$z[[i]])]
    }
    samplePoints$height <- height
  }

  samplePoints <- samplePoints[complete.cases(samplePoints),]

  if(sampleAxis == "lon"){
    samplePoints <- samplePoints[,2:5]
  } else{
    samplePoints <- samplePoints[,-2]
  }

  colnames(samplePoints) <- c("x", "y", "value", "height")

  return(samplePoints)
}

#' @title Plot vertical sample
#'
#' @description Plots cell values along a vertical transect
#'
#' @param rast A multilayer `SpatRaster` object, with names
#' corresponding to the z coordinate represented by the layer.
#' These names must be interpretable by `as.numeric`.
#'
#' @param sampleAxis Specifies whether a latitudinal ("lat") or
#' longitudinal ("long") transect is desired.
#'
#' @param axisValue Numeric value specifying transect postion.
#'
#' @param scaleRange A numeric vector of length 2, specifying
#' the range that should be used for the plot color scale.
#'
#' @param plotLegend `logical`, controls whether legend is plotted.
#'
#' @param depthLim A single vector of class `numeric`. How deep
#' should the plot go?
#'
#' @param transRange A `numeric` vector of lenghth 2. How far
#' along the transect should be plotted?
#'
#' @param transTicks `numeric`, spacing between breaks on x axis.
#'
#' @param verbose `logical`. Switching to `FALSE` mutes message
#' alerting user if input `rast` values exceed specified `scaleRange`.
#'
#' @param ... Additional optional arguments to pass to `viridis`.
#'
#' @note Only unprojected `SpatRaster` files are supported.
#'
#' @return A `ggplot` showing a vertical slice through the `SpatRaster`.
#'
#' @examples
#' library(terra)
#'
#' rast1 <- rast(ncol=10, nrow=10)
#' values(rast1) <- rep(0:3, 50)
#'
#' rast2 <- rast(ncol=10, nrow=10)
#' values(rast2) <- c(rep(0, 50), rep(1,25), rep(2,25))
#'
#' rast3 <- rast(ncol=10, nrow=10)
#' values(rast3) <- rep(c(1,3,2,1), 25)
#'
#' distBrick <- c(rast1, rast2, rast3)
#' names(distBrick) <- c(0:2)
#'
#' transectPlot(distBrick, depthLim = 3)
#'
#'
#' @importFrom ggplot2 ggplot
#' @importFrom metR scale_x_latitude
#'
#' @keywords plotting
#'
#' @export

transectPlot <- function(rast = NULL,
                         sampleAxis = "lon",
                         axisValue = NA,
                         scaleRange = NA,
                         plotLegend = TRUE,
                         depthLim = as.numeric(max(names(rast))),
                         transRange = c(-90,90),
                         transTicks = 20,
                         verbose = FALSE,
                         ...){
  #Input processing
  args <- list(...)

  if("option" %in% names(args)){
    option <- args$option
  } else{
    option <- "plasma"
  }

  if("n" %in% names(args)){
    n <- args$n
  } else{
    n <- 11
  }

  if("legendRound" %in% names(args)){
    legendRound <- args$legendRound
  } else{
    legendRound <- 2
  }

  # Input error checking
  if(any(!grepl("SpatRaster", class(rast)), is.null(rast))){
    warning(paste0("'rast' must be of class 'SpatRaster'.\n"))
    return(NULL)
  }

  nameTest <- suppressWarnings(as.numeric(names(rast)))
  if(any(is.na(nameTest))){
    warning(paste0("Names of 'rast' must be interpretable as 'numeric'.\n"))
    return(NULL)
  }

  if(!(sampleAxis %in% c("lat", "lon"))){
    warning(paste0("'sampleAxis' must be 'lon' or 'lat'."))
    return(NULL)
  }

  if(all(!is.numeric(axisValue), !is.na(axisValue))){
    warning(paste0("'axisValue' must be single numeric value."))
    return(NULL)
  }

  if(!all(is.na(scaleRange))){
    if(!all(any("numeric" %in% class(scaleRange)),
            length(scaleRange) == 2)){
      warning(paste0("'scaleRange' must either be NA or\na numeric vector of length 2."))
      return(NULL)
    }
  }

  # Get vertical transect
  verticalTransect <- try(verticalSample(x = rast, sampleAxis = sampleAxis,
                                     axisValue = axisValue))
  if(is.null(verticalTransect)){
    return(NULL)
  } else {
    # Get information for color scale
    if(any(is.na(scaleRange))){
      begin <- min(verticalTransect$value)
      end <- max(verticalTransect$value)
      scaleRange <- c(begin, end)
    } else if(any(min(verticalTransect$value) < min(scaleRange),
                  max(verticalTransect$value) > max(scaleRange))){
      begin <- min(verticalTransect$value)
      end <- max(verticalTransect$value)

      if(verbose){
        message(paste0("Input extremes exceed specified scale range.\n",
                       "Using input max and min instead."))
      }
    } else{
      begin <- min(scaleRange)
      end <- max(scaleRange)
    }

    at <- seq(from = begin, to = end, by = (end-begin)/n)
    at <- round(at, legendRound)[c(-1,-length(at))]

    begin <- (begin - min(verticalTransect$value)/diff(scaleRange))
    end <- max(verticalTransect$value)/end

    # Tiled heatmap
    # Kluge to get rid of annoying note
    x <- NA
    y <- NA
    value <- NA
    height <- NA

    transect.tile <- ggplot(verticalTransect) +
      geom_tile(aes(x = x, y = y, fill = value, height = height), na.rm = TRUE) +
      coord_cartesian(expand = FALSE) +
      labs(x = NULL, y = "Water Depth (m)") +
      scale_fill_viridis_b(option = option, begin = begin,
                           end = end, breaks = at) +
      theme_bw() +
      theme(panel.background = element_rect(fill = "grey90"),
            panel.grid.major = element_line(linetype = 3, colour = "grey60"),
            axis.text = element_text(colour = 1, size = 10),
            axis.title = element_text(colour = 1, size = 12)) +
      scale_y_reverse() +
      scale_x_latitude(ticks = transTicks, position = "bottom",
                       breaks = seq(transRange[[1]], transRange[[2]],
                                    by = transTicks)) +
      guides(fill = "none") +
      theme(plot.margin = margin(.5,.5,.5,0, "cm")) +
      ylim(depthLim, -0.5) + # Allows plot at surface
      xlim(transRange)

    if(plotLegend){
      transect.tile <- transect.tile +
        guides(fill = guide_legend(title.position = "right", direction = "vertical",
                                   title.theme = element_text(angle = 90, size = 12,
                                                              colour = "black"),
                                   barheight = .5, barwidth = .95,
                                   title.hjust = 0.5,
                                   title = "Value"))
    }
    return(transect.tile)
  }
}
