# Useful functions
# Returns the first argument (typically a directory), if the file or directory
# named by concatenating the first and optionally second argument
# (directory and optional filename) exists
dir_if_exists = $(if $(wildcard $(1)$(2)),$(1))

# Run a shell script if it exists. Stops make on error.
runscript_if_exists =                                                          \
    $(if $(wildcard $(1)),                                                     \
         $(if $(findstring 0,                                                  \
                  $(lastword $(shell $(abspath $(wildcard $(1))); echo $$?))), \
              $(info Info: $(1) success),                                      \
              $(error ERROR: $(1) failed)))

# For message printing: pad the right side of the first argument with spaces to
# the number of bytes indicated by the second argument.
space_pad_to = $(shell echo $(1) "                                                      " | head -c$(2))

# Call with some text, and a prefix tag if desired (like [AUTODETECTED]),
show_config_info = $(call arduino_output,- $(call space_pad_to,$(2),20) $(1))

# Call with the name of the variable, a prefix tag if desired (like [AUTODETECTED]),
# and an explanation if desired (like (found in $$PATH)
show_config_variable = $(call show_config_info,$(1) = $($(1)) $(3),$(2))

# Just a nice simple visual separator
show_separator = $(call arduino_output,-------------------------)

$(call show_separator)
$(call arduino_output,Arduino.mk Configuration:)

########################################################################
#
# Detect OS
ifeq ($(OS),Windows_NT)
    CURRENT_OS = WINDOWS
else
    UNAME_S := $(shell uname -s)
    ifeq ($(UNAME_S),Linux)
        CURRENT_OS = LINUX
    endif
    ifeq ($(UNAME_S),Darwin)
        CURRENT_OS = MAC
    endif
endif
$(call show_config_variable,CURRENT_OS,[AUTODETECTED])

########################################################################
#
# Travis-CI
ifneq ($(TEST),)
       DEPENDENCIES_DIR = /var/tmp/Arduino-Makefile-testing-dependencies

       DEPENDENCIES_MPIDE_DIR = $(DEPENDENCIES_DIR)/mpide-0023-linux64-20130817-test
       ifeq ($(MPIDE_DIR),)
              MPIDE_DIR = $(DEPENDENCIES_MPIDE_DIR)
       endif

       DEPENDENCIES_ARDUINO_DIR = $(DEPENDENCIES_DIR)/arduino-1.0.6
       ifeq ($(ARDUINO_DIR),)
              ARDUINO_DIR = $(DEPENDENCIES_ARDUINO_DIR)
       endif
endif

########################################################################
# Arduino Directory

ifndef ARDUINO_DIR
    AUTO_ARDUINO_DIR := $(firstword \
        $(call dir_if_exists,/usr/share/arduino) \
        $(call dir_if_exists,/Applications/Arduino.app/Contents/Resources/Java) \
        $(call dir_if_exists,/Applications/Arduino.app/Contents/Java) )
    ifdef AUTO_ARDUINO_DIR
       ARDUINO_DIR = $(AUTO_ARDUINO_DIR)
       $(call show_config_variable,ARDUINO_DIR,[AUTODETECTED])
    else
        echo $(error "ARDUINO_DIR is not defined")
    endif
else
    $(call show_config_variable,ARDUINO_DIR,[USER])
endif

ifeq ($(CURRENT_OS),WINDOWS)
    ifneq ($(shell echo $(ARDUINO_DIR) | egrep '^(/|[a-zA-Z]:\\)'),)
        echo $(error On Windows, ARDUINO_DIR must be a relative path)
    endif
endif