# packages.R
#
# PACKAGE MANAGEMENT FOR SMARTCANE
# ===============================
# This script centralizes all package dependencies for the SmartCane project.
# It installs missing packages and loads all required libraries.
#

#' Check and install packages if needed
#'
#' @param pkg_list List of packages to check and install
#' @param install_missing Whether to install missing packages
#' @return Vector of packages that couldn't be installed (if any)
#'
check_and_install_packages <- function(pkg_list, install_missing = TRUE) {
  # Check which packages are already installed
  is_installed <- pkg_list %in% rownames(installed.packages())
  missing_pkgs <- pkg_list[!is_installed]
  
  # Install missing packages if requested
  failed_pkgs <- character(0)
  if (length(missing_pkgs) > 0) {
    if (install_missing) {
      message("Installing ", length(missing_pkgs), " missing packages...")
      for (pkg in missing_pkgs) {
        tryCatch({
          install.packages(pkg, repos = "https://cran.rstudio.com/", dependencies = TRUE)
          message("  Installed: ", pkg)
        }, error = function(e) {
          warning("Failed to install package: ", pkg)
          warning("Error: ", e$message)
          failed_pkgs <<- c(failed_pkgs, pkg)
        })
      }
    } else {
      message("The following packages are required but not installed:")
      message(paste(missing_pkgs, collapse = ", "))
      failed_pkgs <- missing_pkgs
    }
  } else {
    message("All required packages are already installed.")
  }
  
  return(failed_pkgs)
}

#' Load all required packages for SmartCane project
#'
#' @param verbose Whether to show messages during loading
#' @return Logical indicating success (TRUE if all packages loaded)
#'
load_smartcane_packages <- function(verbose = FALSE) {
  # Define all required packages
  required_packages <- c(
    # Geospatial packages
    "sf",          # Simple Features for spatial vector data
    "terra",       # Raster data processing
    "exactextractr", # Fast extraction from rasters
    "raster",      # Legacy raster package (for compatibility)
    
    # Data manipulation
    "tidyverse",   # Collection of data manipulation packages
    "lubridate",   # Date manipulation
    "readxl",      # Excel file reading
    "stringr",     # String manipulation
    "purrr",       # Functional programming tools
    
    # Visualization
    "ggplot2",     # Advanced plotting
    "leaflet",     # Interactive maps
    "plotly",      # Interactive plots
    
    # Project management
    "here",        # Path handling
    
    # Document generation
    "knitr",       # Dynamic report generation
    "rmarkdown"    # R Markdown processing
  )
  
  # Check and install missing packages
  failed_pkgs <- check_and_install_packages(required_packages)
  
  # Load all installed packages
  success <- TRUE
  for (pkg in setdiff(required_packages, failed_pkgs)) {
    tryCatch({
      if (verbose) message("Loading package: ", pkg)
      suppressPackageStartupMessages(library(pkg, character.only = TRUE))
    }, error = function(e) {
      warning("Failed to load package: ", pkg)
      warning("Error: ", e$message)
      success <- FALSE
    })
  }
  
  # Report any issues
  if (length(failed_pkgs) > 0) {
    warning("The following packages could not be installed: ", 
            paste(failed_pkgs, collapse = ", "))
    success <- FALSE
  }
  
  return(success)
}

# Run the loading function if the script is sourced directly
if (!exists("skip_package_loading") || !skip_package_loading) {
  load_smartcane_packages()
}