require 'vstudioide/sln_document'


module VStudioIDE

  class Solution
    
    def initialize(file)
      @file = file
      parse
    end
    
    def configurations
      @sln.configurations
    end
    
    private
      def parse
        File.open(@file) do |io|
          @sln = SLN.load(io)
        end
      end
    
  end
  
  
  class SLN
    @@formats = []
    
    def self.inherited(format)
      @@formats << format
    end
    
    def self.load(io)
      # Loop until we read a line that begins with a word charachter.  This
      # scans past garbage that certain versions of Visual Studio put at the
      # beginning of the file.
      while io.gets
        break if $_.match('\A\w')
      end
      
      sln = nil
      version = $_.strip
      
      @@formats.each do |format|
        sln = format.new if format.loads? version
      end
      raise IOError, "Unrecognized Visual Studio solution format." if sln.nil?
      
      sln.parse(io)
      sln
    end
    
    
    def self.loads?(format)
      false
    end
    
    def configurations
      []
    end
  end
  
  class SLNv8 < SLN
    FORMAT = "Microsoft Visual Studio Solution File, Format Version 8.00".freeze
    
    def self.loads?(format)
      true if FORMAT == format
    end
    
    def parse(io)
      @doc = SLNDocument.new(io)
    end
    
    def configurations
      sc = @doc.global['SolutionConfiguration']
      return [] if sc.nil?
      
      configs = []
      
      sc.each do |config|
        idx = config.index('=')
        configs << config.slice(0, idx).strip
      end
      
      return configs
    end
  end
  
  class SLNv9 < SLN
    FORMAT = "Microsoft Visual Studio Solution File, Format Version 9.00".freeze
    
    def self.loads?(format)
      true if FORMAT == format
    end
    
    def parse(io)
      @doc = SLNDocument.new(io)
    end
    
    def configurations
      sc = @doc.global['SolutionConfigurationPlatforms']
      return [] if sc.nil?
      
      configs = []
      
      sc.each do |config|
        idx = config.index('|')
        configs << config.slice(0, idx).strip
      end
      
      return configs
    end
  end
  
end