add optional line item columns width configuration (#35)

Make line items table column widths configurable

Co-authored-by: whysthatso <git@whysthatso.net>
Co-authored-by: Chris Oliver <excid3@gmail.com>

README.md

@@ -16,11 +16,15 @@ gem 'receipts'
 
 And then execute:
 
-    $ bundle
+```sh
+$ bundle
+```
 
 Or install it yourself as:
 
-    $ gem install receipts
+```sh
+$ gem install receipts
+```
 
 ## Usage
 
@@ -124,14 +128,32 @@ Here's an example of where each option is displayed.
 
 ![options](examples/images/options.jpg)
 
+#### Line Items Table - Column Widths
+
+You may set an option to configure the line items table's columns width in order to accommodate shortcomings of Prawn's width guessing ability to render header and content reasonably sized.
+The configuration depends on your line item column count and follows the prawn/table configuration as documented [here](https://prawnpdf.org/prawn-table-manual.pdf):
+
+This will size the second column to 400 and the fourth column to 50.
+
+```ruby
+column_widths: {1 => 400,3 => 50 }
+```
+
+This will set all column widths, considering your table has 4 columns.
+
+```ruby
+column_widths: [100, 200, 240]
+```
+
+If not set, it will fall back to Prawn's default behavior.
+
 ### Formatting
 
 `details` and `line_items` allow inline formatting with Prawn. This allows you to use HTML tags to format text: `<b>` `<i>` `<u>` `<strikethrough>` `<sub>` `<sup>` `<font>` `<color>` `<link>`
 
 See [the Prawn docs](https://prawnpdf.org/api-docs/2.3.0/Prawn/Text.html#text-instance_method) for more information.
 
-
-##### Page Size
+#### Page Size
 
 You can specify a different page size by passing in the `page_size` keyword argument:
 
@@ -216,7 +238,7 @@ class ChargesController < ApplicationController
       @charge = current_user.charges.find(params[:id])
     end
 
-  	def send_pdf
+    def send_pdf
       # Render the PDF in memory and send as the response
       send_data @charge.receipt.render,
         filename: "#{@charge.created_at.strftime("%Y-%m-%d")}-gorails-receipt.pdf",
@@ -312,9 +334,8 @@ Receipts::Statement.new(
 
 ## Contributing
 
-1. Fork it ( https://github.com/excid3/receipts/fork )
+1. Fork it [https://github.com/excid3/receipts/fork](https://github.com/excid3/receipts/fork)
 2. Create your feature branch (`git checkout -b my-new-feature`)
 3. Commit your changes (`git commit -am 'Add some feature'`)
 4. Push to the branch (`git push origin my-new-feature`)
 5. Create a new Pull Request
-

lib/receipts/base.rb

@@ -7,7 +7,7 @@ class << self
     end
 
     def initialize(attributes = {})
-      super page_size: attributes.delete(:page_size) || "LETTER"
+      super(page_size: attributes.delete(:page_size) || "LETTER")
       setup_fonts attributes.fetch(:font, Receipts.default_font)
 
       @title = attributes.fetch(:title, self.class.title)
@@ -22,7 +22,10 @@ def generate_from(attributes)
       header company: company, height: attributes.fetch(:logo_height, 16)
       render_details attributes.fetch(:details)
       render_billing_details company: company, recipient: attributes.fetch(:recipient)
-      render_line_items attributes.fetch(:line_items)
+      render_line_items(
+        line_items: attributes.fetch(:line_items),
+        column_widths: attributes[:column_widths]
+      )
       render_footer attributes.fetch(:footer, default_message(company: company))
     end
 
@@ -79,11 +82,18 @@ def render_billing_details(company:, recipient:, margin_top: 16)
       table(line_items, width: bounds.width, cell_style: {borders: [], inline_format: true, overflow: :expand})
     end
 
-    def render_line_items(line_items, margin_top: 30)
+    def render_line_items(line_items:, margin_top: 30, column_widths: nil)
       move_down margin_top
 
       borders = line_items.length - 2
-      table(line_items, width: bounds.width, cell_style: {border_color: "eeeeee", inline_format: true}) do
+
+      table_options = {
+        width: bounds.width,
+        cell_style: {border_color: "eeeeee", inline_format: true},
+        column_widths: column_widths
+      }.compact
+
+      table(line_items, table_options) do
         cells.padding = 6
         cells.borders = []
         row(0..borders).borders = [:bottom]