Initial import

lib/picop/source_file.rb

@@ -0,0 +1,65 @@
+require "yaml"
+require "digest"
+
+module Picop
+  class SourceFile
+    attr_reader :file_path, :content
+
+    METADATA_PATTERN = /^\s*#\s*@META_START\n(.*?)^\s*#\s*@META_END/m
+
+    def initialize(file_path)
+      @file_path = file_path
+      @content = File.read(file_path)
+    end
+
+    def metadata
+      @metadata ||= begin
+        return {} unless content =~ METADATA_PATTERN
+    
+        yaml_content = $1.lines.map do |line|
+          line.sub(/^\s*#\s?/, '').rstrip
+        end.join("\n")
+    
+        YAML.safe_load(yaml_content)
+      end
+    end
+
+    def file_content = content.sub(/^\s*#\s*@META_START\n.*?^\s*#\s*@META_END\n*/m, '')
+
+    def checksum = "sha256:#{Digest::SHA256.hexdigest(file_content)}"
+
+    def show = puts(metadata.merge({checksum: checksum}))
+
+    def save = File.write(file_path, content)
+
+    def add_metadata(metadata_hash)
+      yaml_content = metadata_hash.to_yaml.strip
+      metadata_block = [
+        "# @META_START",
+        yaml_content.lines.map { |line| "# #{line}" }.join,
+        "# @META_END"
+      ].join("\n")
+
+      if content =~ METADATA_PATTERN
+        @content = content.sub(METADATA_PATTERN, metadata_block)
+      else
+        @content = [metadata_block, content].join("\n\n")
+      end
+    end
+    
+    def sign
+      hash = checksum
+      meta = metadata || {}
+      return puts "File already signed" if meta['content_checksum'] == hash
+    
+      meta['content_checksum'] = "#{hash}"
+      add_metadata(meta)
+      save
+    end
+
+    def verify
+      return false unless metadata.key? 'content_checksum'
+      checksum == metadata['content_checksum']
+    end
+  end
+end