From bfd07bea401783ffa1166551edaf49fc8b70e098 Mon Sep 17 00:00:00 2001
From: Nisha Bagyam Nallasivam <nisha.nallasivam@gusto.com>
Date: Fri, 21 Feb 2020 16:20:32 -0800
Subject: [PATCH] Ruby version

---
 src-ruby/parser.rb | 112 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 112 insertions(+)
 create mode 100644 src-ruby/parser.rb

diff --git a/src-ruby/parser.rb b/src-ruby/parser.rb
new file mode 100644
index 0000000..69b45ba
--- /dev/null
+++ b/src-ruby/parser.rb
@@ -0,0 +1,112 @@
+require 'aws-sdk-textract'
+
+class AwsTextractParser
+   attr_reader :filename, :bucket
+
+   def initialize(filename, bucket)
+     @filename = filename
+     @bucket = bucket
+   end
+
+   def parse
+     {
+       kv: parse_key_value_pairs,
+       lines: parse_lines
+     }
+   end
+
+   def parse_key_value_pairs
+     key_value_pairs = {}
+     key_map, value_map, block_map = get_kv_map
+     kvs = get_kv_relationship(key_map, value_map, block_map)
+     kvs.each do |key, value|
+       key_value_pairs[key] = value
+     end
+     key_value_pairs
+   end
+
+  def parse_lines
+    lines = []
+    response.blocks.each do |block|
+      if block.block_type == "LINE"
+        lines << block.text
+      end
+    end
+    lines
+  end
+
+  def response
+    client = Aws::Textract::Client.new
+    @response ||= client.analyze_document({ document: {s3_object: {bucket: bucket, name: filename}}, feature_types: ["FORMS", "TABLES"]})
+  end
+
+
+   def get_kv_map
+     blocks = response.blocks
+     key_map = {}
+     value_map = {}
+     block_map = {}
+     blocks.each do |block|
+
+       block_id = block.id
+       block_map[block_id] = block
+       if block.block_type == "KEY_VALUE_SET"
+         if  block.entity_types.include?('KEY')
+           key_map[block_id] = block
+         else
+           value_map[block_id] = block
+         end
+       end
+     end
+     [key_map, value_map, block_map]
+   end
+
+
+   def get_kv_relationship(key_map, value_map, block_map)
+     kvs = {}
+     key_map.each do |_block_id, key_block|
+       value_block = find_value_block(key_block, value_map)
+       key = get_text(key_block, block_map)
+       val = get_text(value_block, block_map)
+       kvs[key] = val
+     end
+     kvs
+   end
+
+
+   def find_value_block(key_block, value_map)
+     value_block = []
+     key_block.relationships.each do |relationship|
+       if relationship.type == 'VALUE'
+         relationship.ids.each do |value_id|
+           value_block = value_map[value_id]
+         end
+       end
+     end
+     value_block
+   end
+
+   def get_text(result, blocks_map)
+     text = ''
+
+     return if result.relationships.nil?
+
+     result.relationships.each do |relationship|
+       if relationship.type == 'CHILD'
+         relationship.ids.each do |child_id|
+           word = blocks_map[child_id]
+           if word.block_type == 'WORD'
+             text += word.text + ' '
+           end
+
+           if word.block_type == 'SELECTION_ELEMENT'
+             if word.selection_status == 'SELECTED'
+               text += 'X '
+             end
+           end
+         end
+       end
+     end
+     text
+   end
+end