DWD: Climate Water Balance

library(kwb.impetus)
summarise_means <- function(data) {
  data %>%
    dplyr::summarise(
      q05 = quantile(.data$mean, probs = 0.05),
      q95 = quantile(.data$mean, probs = 0.95),
      mean = mean(.data$mean)
    )  
}


decade_year_sums <- function(data, 
                             full_years = TRUE,
                             unit = "mm/a") {
  
  years <- unique(data$year)
  
  if(full_years) {
    years <- data %>%  
      dplyr::count(Decade, Decade_Label, Year) %>% 
      dplyr::filter(.data$n == 12) %>% 
      dplyr::pull(.data$Year)
  }
  
  data %>% 
    dplyr::filter(.data$year %in% years) %>% 
    dplyr::group_by(Decade, Decade_Label, Year) %>%  
    dplyr::summarise(mean = sum(mean)) %>% 
    summarise_means() %>% 
    dplyr::mutate(Decade_Label_new = sprintf("%s\nq95: %3.1f %s\nmean: %3.1f %s\nq05: %3.1f %s",
                                             .data$Decade_Label, 
                                             .data$q95, 
                                             unit,
                                             .data$mean,
                                             unit,
                                             .data$q05,
                                             unit))
  
}

filter_for_max_year <- function(data) {
  data[data$Year == max(data$Year),]
}

plot_yearly <- function(data, y_label) {
  data %>%  
    dplyr::group_by(year) %>% 
    dplyr::summarise(mean = sum(mean)) %>% 
    dplyr::mutate(
      Year = as.integer(.data$year), 
      Decade = kwb.impetus::floor_decade(.data$year),
      Decade_Label = kwb.impetus::decade_label(.data$Decade)) %>%
    ggplot2::ggplot(mapping = ggplot2::aes(x = year, 
                                           y = mean)) +
                      ggplot2::geom_point() +
                      ggplot2::geom_line() +
    ggplot2::theme_bw() +
    ggplot2::labs(x = "Year", 
                  y = sprintf("%s (mm/a)", y_label))
  }

plot_decades <- function(data, unit = "mm/a") {
  
  decade_sums <- decade_year_sums(data) %>% 
    dplyr::ungroup() %>% 
    dplyr::select(Decade_Label, 
                  Decade_Label_new)
  
  
  aggregated_data <- data %>% 
    kwb.impetus::group_by_decade_month_label() %>% 
    summarise_means() %>% 
    dplyr::ungroup() %>% 
    dplyr::left_join(decade_sums, by = "Decade_Label") %>% 
    dplyr::select(-.data$Decade_Label) %>% 
    dplyr::rename(Decade_Label = .data$Decade_Label_new)
  
  
  decades <- kwb.impetus::decades_tibble(
    decade_labels = aggregated_data$Decade_Label,
    colors = c('darkgreen', 'lightgreen', 'orange', 'red')
  )
  
  p1 <- aggregated_data
  
  p2 <- data %>% 
    filter_for_max_year() %>% 
    kwb.impetus::group_by_decade_label() %>% 
    kwb.impetus::group_by_year_month() %>% 
    summarise_means()
  
  p1 %>% 
    ggplot2::ggplot(mapping = ggplot2::aes(
      x = as.integer(.data$Month), 
      y = .data$mean,
      col = as.factor(.data$Decade_Label)
    )) + 
    #ggplot2::geom_point(alpha = 0.5) + 
    kwb.impetus::decade_ribbons() +
    kwb.impetus::scale_fill_decades(decades) +
    kwb.impetus::scale_color_decades(decades) +
    ggplot2::geom_point() +
    ggplot2::geom_point(ggplot2::aes(
      x = as.integer(.data$Month),
      y = .data$mean
    ),
    data = p2,
    col = "darkgrey",
    alpha = 0.5,
    inherit.aes = FALSE,
    show.legend = FALSE
    ) +
    kwb.impetus::ggplot2_scale_x_continuous_12() +
    #ggplot2::geom_boxplot() +
    ggplot2::facet_wrap( 
      ~ .data$Decade_Label,
      nrow = 1L, 
      ncol = length(unique(p1$Decade_Label))
    ) +
    ggplot2::theme_bw() + 
    ggplot2::theme(legend.position = "bottom") +
    ggplot2::labs(
      y = sprintf("Mean '%s' (%s)", 
                  parameter_name, 
                  unit), 
      x = "Month Number", 
      col = "Mean", 
      fill = "5%/95% Conf.-Interval",
      title = unique(p1$Label)
    )
}


print_to_pdf <- function(gg, file, width.cm) {
  
  kwb.utils::preparePdf(
    file, 
    landscape = TRUE, 
    width.cm = width.cm, 
    height.cm = 21
  )
  
  on.exit(dev.off())
  
  print(gg)
}