#
#--
# Copyright (c) 2005-2007, John Mettraux, OpenWFE.org
# All rights reserved.
# 
# Redistribution and use in source and binary forms, with or without 
# modification, are permitted provided that the following conditions are met:
# 
# . Redistributions of source code must retain the above copyright notice, this
#   list of conditions and the following disclaimer.  
# 
# . Redistributions in binary form must reproduce the above copyright notice, 
#   this list of conditions and the following disclaimer in the documentation 
#   and/or other materials provided with the distribution.
# 
# . Neither the name of the "OpenWFE" nor the names of its contributors may be
#   used to endorse or promote products derived from this software without
#   specific prior written permission.
# 
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" 
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 
# ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE 
# LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 
# CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 
# SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
# INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
# CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 
# ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
# POSSIBILITY OF SUCH DAMAGE.
#++
#
# $Id: utils.rb 3454 2006-10-08 16:51:00Z jmettraux $
#

#
# "hecho en Costa Rica" and "made in Japan"
#
# john.mettraux@openwfe.org
#

module OpenWFE

    #
    # Returns the first subelt of xmlElt that matches the given xpath.
    # If xpath is null, the first elt will be returned.
    #
    def OpenWFE.first_element (xmlElt, elementName=nil)

        return nil if not xmlElt

        return xmlElt.elements[1] if not elementName

        #xmlElt.elements.each do |elt|
        #    return elt if elt.name == elementName
        #end
        #return nil
        xmlElt.elements.detect { |elt| elt.name == elementName }
    end

    #
    # Used in tests, is equivalent to Perl's die() method.
    #
    def OpenWFE.die (text)
        puts text
        exit 1
    end

    #
    # Attempts a deep cloning of the object
    #
    def OpenWFE.copy (object)

        return nil if object == nil

        if object.kind_of?(Array)
            result = []
            object.each do |i|
                result << copy(i)
            end
            return result
        end

        if object.kind_of?(Hash)
            result = {}
            object.each do |k, v|
                result[copy(k)] = copy(v)
            end
            return result
        end

        return object.dup
    end

    #
    # an automatic dup implementation attempt
    #
    def OpenWFE.fulldup (object)

        return nil if object == nil

        return object if object.kind_of? Fixnum
        return object if object.kind_of? TrueClass
        return object if object.kind_of? FalseClass

        return object.dup if object.kind_of? String

        o = object.class.new

        #
        # some kind of collection ?

        if object.kind_of? Array
            object.each do |i|
                o << fulldup(i)
            end
        elsif object.kind_of? Hash
            object.each do |k, v|
                o[copy(k)] = fulldup(v)
            end
        end

        #
        # duplicate the attributes of the object

        object.instance_variables.each do |v|

            #puts "v is #{v}"

            value = object.instance_variable_get(v)

            #puts "value is '#{value}'"

            value = fulldup(value)

            begin
                o.instance_variable_set(v, value)
            rescue
                # ignore, must be readonly
            end
        end

        return o
    end

    def OpenWFE.to_underscore (string)
        string.gsub("-", "_")
    end

    def OpenWFE.to_dash (string)
        string.gsub("_", "-")
    end

    #
    # Returns true if the given string starts with the 'start' string.
    #
    def OpenWFE.starts_with (string, start)
        #
        # my favourite way of doing that would be by adding this 
        # method to the String class, but that could be intrusive
        # (as OpenWFE is meant at first as an embeddable workflow engine).
        #
        return false unless string
        return false if string.length < start.length
        return string[0, start.length] == start
    end

    #
    # Returns true if the given string ends with the '_end' string.
    #
    def OpenWFE.ends_with (string, _end)
        return false unless string
        return false if string.length < _end.length
        return string[-_end.length..-1] == _end
    end

    #
    # Attempts at displaying a nice stack trace
    #
    def OpenWFE.exception_to_s (exception)
        s = ""
        s << "#{exception}\n"
        s << exception.backtrace.join("\n")
        return s
    end

    #
    # Pretty printing a caller() array
    #
    def OpenWFE.caller_to_s (start_index, max_lines=nil)
        s = ""
        caller(start_index + 1).each_with_index do |line, index|
            break if max_lines and index >= max_lines
            s << "   #{line}\n"
        end
        return s
    end

    #
    # A small Timer class for debug purposes.
    #
    class Timer

        attr_reader :start

        def initialize
            @start = Time.now.to_f
        end

        def duration
            return (Time.now.to_f - @start) * 1000
        end
    end
    
end