map.R

# \\\
# Copyright 2021-2022 Louis Héraut*1
#
# *1   INRAE, France
#      louis.heraut@inrae.fr
#
# This file is part of ash R toolbox.
#
# ash R toolbox is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or (at
# your option) any later version.
#
# ash R toolbox is distributed in the hope that it will be useful, but 
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with ash R toolbox.  If not, see <https://www.gnu.org/licenses/>.
# ///
#
#
# plotting/map.R
#
# Deals with the creation of a map for presenting the trend analysis of hydrological variables


## 1. MAP PANEL
# Generates a map plot of the tendancy of a hydrological variable
map_panel = function (list_df2plot, df_meta, df_shapefile, idPer=1, outdirTmp='', codeLight=NULL, margin=NULL, showSea=TRUE, verbose=TRUE) {

    # Extract shapefiles
    df_france = df_shapefile$france
    df_bassin = df_shapefile$bassin
    df_river = df_shapefile$river

    # Number of variable/plot
    nbp = length(list_df2plot)
  
    # Get all different stations code
    Code = levels(factor(df_meta$code))
    nCode = length(Code)

    # Gets a trend example
    df_trend = list_df2plot[[1]]$trend
    
    nPeriod_max = 0
    for (code in Code) {
        # Extracts the trend corresponding to the code
        df_trend_code = df_trend[df_trend$code == code,]
        
        # Extract start and end of trend periods
        Start = df_trend_code$period_start
        End = df_trend_code$period_end
        # Get the name of the different period
        UStart = levels(factor(Start))        
        UEnd = levels(factor(End))

        # Compute the max of different start and end
        # so the number of different period
        nPeriod = max(length(UStart), length(UEnd))

        # If the number of period for the trend is greater
        # than the current max period, stocks it
        if (nPeriod > nPeriod_max) {
            nPeriod_max = nPeriod
        }
    }