Class: Pdf::Toolkit

Inherits:
Object
  • Object
show all
Defined in:
app/services/pdf/toolkit.rb

Overview

Bounded, programmatic PDF operations backed by HexaPDF 1.9 — the engine
behind the Sunny pdf_tools service (Assistant::PdfToolBuilder).

Every method loads HexaPDF lazily (Loader.load!) and operates on a
local file path. Transform methods return a Result carrying the output PDF
+bytes+ plus a small descriptive +meta+ hash; Toolkit.inspect_pdf returns a
meta-only Result (+bytes+ nil); Toolkit.split returns an Array of Results.

This is deliberately a curated operation set — not raw HexaPDF — so it can
be driven safely by the LLM tool loop (no arbitrary code execution):

inspect_pdf — structure, AcroForm fields, text preview, image count
stamp — overlay text / cover (redact) / image / watermark on pages
fill_form — set AcroForm field values, optionally flatten
merge — concatenate several PDFs
split — explode into per-page (or per-range) PDFs
rotate — rotate selected pages by a multiple of 90°
select_pages — keep/reorder a subset (covers extract, delete, reorder)
compress — Ghostscript size reduction (delegates to Compressor)
generate — build a new branded PDF from a declarative layout

Coordinates use the PDF user-space convention: points (1/72") measured from
the page's lower-left corner, +x right, +y up.

Defined Under Namespace

Classes: Error, Result

Constant Summary collapse

NIMBUS =

Brand fonts (mirrors Base). Relative paths resolve from Rails root.

'data/fonts/NimbusSans.ttf'
NIMBUS_BOLD = 
'data/fonts/NimbusSansBold.ttf'
SOFIA =

WarmlyYours website design-system fonts, converted (lossless woff2→sfnt) from
the self-hosted webfonts in public/fonts/ so generated PDFs match warmlyyours.com:
Sofia Pro is the site's primary sans (body), Orpheus Pro its serif display face.

'data/fonts/sofiapro/SofiaPro-Regular.ttf'
SOFIA_LIGHT = 
'data/fonts/sofiapro/SofiaPro-Light.ttf'
SOFIA_BOLD = 
'data/fonts/sofiapro/SofiaPro-Semibold.ttf'
ORPHEUS = 
'data/fonts/orpheuspro/OrpheusPro-Regular.ttf'
ORPHEUS_BOLD = 
'data/fonts/orpheuspro/OrpheusPro-Bold.ttf'
FONT_SPECS =

Logical font name → [hexapdf font spec, kwargs].

{
  'helvetica'      => ['Helvetica', {}],
  'helvetica_bold' => ['Helvetica', { variant: :bold }],
  'sofia'          => [SOFIA, {}],
  'sofia_bold'     => [SOFIA_BOLD, {}],
  'sofia_light'    => [SOFIA_LIGHT, {}],
  'orpheus'        => [ORPHEUS, {}],
  'orpheus_bold'   => [ORPHEUS_BOLD, {}],
  'nimbus'         => [NIMBUS, {}],
  'nimbus_bold'    => [NIMBUS_BOLD, {}]
}.freeze
LH_BURGUNDY =

WarmlyYours letterhead chrome (matches the approved cover-letter sample).
Contact strings default to the sample's presentation; CompanyConstants holds
the underlying data (PHONE[:usa], ADDRESS[:usa]). Override via the layout.

'922328'
LH_INK =

logo wordmark, tagline, H1, footer separators

'262626'
LH_RULE =

body text

'd9d2d0'
LH_TAGLINE =

header/footer hairline

'Modern Radiant Heating Solutions'
LH_PHONE = 
'1 (800) 875-5285'
LH_ADDRESS = 
'590 Telser Rd Suite B, Lake Zurich, IL, 60047'
LH_WEBSITE = 
'www.WarmlyYours.com'
LH_SIDE =

Page geometry in PostScript points (US Letter). Margins clear the header/footer
bands so flowing content never collides with the chrome drawn in the post-pass.

72
LH_TOP_MARGIN = 
128
LH_BOTTOM_MARGIN = 
100
MAX_TEXT_PREVIEW_CHARS =

Per-page text preview cap (chars) returned by inspect_pdf.

1_500
MAX_TEXT_PREVIEW_PAGES =

Max pages scanned for text preview.

10

Class Method Summary collapse

Class Method Details

.compress(path, level: '/printer') ⇒ Result

Reduce file size via Ghostscript. No-op (returns input) when gs is absent.

Parameters:

Returns:



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# File 'app/services/pdf/toolkit.rb', line 300

def compress(path, level: '/printer')
  blob = File.binread(path)
  res  = Pdf::Compressor.new(input_blob: blob, pdf_setting: level).compress
  out  = res.output_blob || blob

  Result.new(bytes: out,
             meta: { status: res.result.to_s, original_bytes: blob.bytesize, new_bytes: out.bytesize,
                     saved_bytes: [blob.bytesize - out.bytesize, 0].max })
end

.fill_form(path, values:, flatten: false) ⇒ Result

Set AcroForm field values by full field name.

Parameters:

  • path (String)
  • values (Hash{String=>Object}) —

    field name → value

  • flatten (Boolean) (defaults to: false) —

    bake values into page content (no longer editable)

Returns:



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# File 'app/services/pdf/toolkit.rb', line 163

def fill_form(path, values:, flatten: false)
  Pdf::Loader.load!
  raise Error, 'values must be a non-empty map of field_name => value' unless values.is_a?(Hash) && values.any?

  doc  = HexaPDF::Document.open(path)
  form = doc.acro_form
  raise Error, 'This PDF has no fillable form fields (no AcroForm). Use stamp to overlay text instead.' unless form

  applied = []
  unknown = []
  failed  = []
  values.each do |name, val|
    field = form.field_by_name(name.to_s)
    if field.nil?
      unknown << name.to_s
      next
    end
    begin
      field.field_value = coerce_field_value(field, val)
      applied << name.to_s
    rescue StandardError => e
      failed << { field: name.to_s, error: e.message }
    end
  end

  form.create_appearances
  form.flatten if flatten

  Result.new(bytes: write(doc),
             meta: { applied: applied, unknown_fields: unknown, failed: failed,
                     flattened: !!flatten, pages: doc.pages.count })
rescue HexaPDF::Error => e
  raise Error, "Fill form failed: #{e.message}"
end

.generate(layout:) ⇒ Result

Build a new branded PDF from a declarative layout.
{ title:, subtitle:, logo: true, page_size: "Letter", orientation: "portrait",
blocks: [ { type: "heading"|"paragraph"|"bullets"|"spacer", ... } ] }

Parameters:

  • layout (Hash)

Returns:



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# File 'app/services/pdf/toolkit.rb', line 317

def generate(layout:)
  Pdf::Loader.load!
  layout = symbolize(layout)
  return generate_letterhead(layout) if layout[:template].to_s == 'letterhead'

  composer = HexaPDF::Composer.new(
    page_size:        (layout[:page_size] || 'Letter').to_sym,
    page_orientation: (layout[:orientation] || 'portrait').to_sym,
    margin:           [54, 54, 54, 54]
  )
  configure_brand(composer.document)
  apply_generate_styles(composer)

  if layout.fetch(:logo, true) && File.exist?(Pdf::Config::LOGO_PATH)
    composer.image(Pdf::Config::LOGO_PATH, width: 180)
    composer.text(' ', font_size: 8)
  end
  composer.text(layout[:title].to_s, style: :gen_title)       if present?(layout[:title])
  composer.text(layout[:subtitle].to_s, style: :gen_subtitle) if present?(layout[:subtitle])
  composer.text(' ', font_size: 6)

  Array(layout[:blocks]).each { |b| render_block(composer, symbolize(b)) }

  Result.new(bytes: write_composer(composer), meta: { pages: composer.document.pages.count })
rescue HexaPDF::Error => e
  raise Error, "Generate failed: #{e.message}"
end

.inspect_pdf(path) ⇒ Result

Read structure and content of a PDF without modifying it.

Parameters:

  • path (String) —

    local file path

Returns:

  • (Result) —

    meta-only (bytes nil)



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# File 'app/services/pdf/toolkit.rb', line 91

def inspect_pdf(path)
  Pdf::Loader.load!
  doc  = HexaPDF::Document.open(path)
  info = doc.trailer.info

  sizes = doc.pages.map do |pg|
    mb = pg.box(:media)
    { width: mb.width.round(1), height: mb.height.round(1), rotation: (pg[:Rotate] || 0).to_i }
  end

  form   = doc.acro_form
  fields = []
  form&.each_field do |f|
    fields << {
      name:  f.full_field_name,
      type:  (f.concrete_field_type || f.field_type).to_s,
      value: stringify(f.field_value)
    }
  end

  Result.new(meta: {
    pages:        doc.pages.count,
    encrypted:    doc.encrypted?,
    page_sizes:   sizes,
    has_acroform: !form.nil?,
    field_count:  fields.size,
    fields:       fields,
    image_count:  image_count(doc),
    title:        present_str(info[:Title]),
    author:       present_str(info[:Author]),
    producer:     present_str(info[:Producer]),
    text_preview: text_preview(path)
  })
rescue HexaPDF::Error => e
  raise Error, "Could not read PDF: #{e.message}"
end

.merge(paths:) ⇒ Result

Concatenate several PDFs into one, in the order given.

Parameters:

  • paths (Array<String>)

Returns:



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# File 'app/services/pdf/toolkit.rb', line 203

def merge(paths:)
  Pdf::Loader.load!
  raise Error, 'merge needs at least one source PDF' if Array(paths).empty?

  target = HexaPDF::Document.new
  total  = 0
  Array(paths).each do |p|
    src = HexaPDF::Document.open(p)
    src.pages.each do |pg|
      target.pages << target.import(pg)
      total += 1
    end
  end
  raise Error, 'no pages found across sources' if total.zero?

  Result.new(bytes: write(target), meta: { pages: total, sources: Array(paths).size })
rescue HexaPDF::Error => e
  raise Error, "Merge failed: #{e.message}"
end

.rotate(path, degrees:, pages: :all) ⇒ Result

Rotate selected pages by a multiple of 90° (clockwise).

Parameters:

  • path (String)
  • degrees (Integer)
  • pages (:all, Integer, Array<Integer>) (defaults to: :all)

Returns:



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# File 'app/services/pdf/toolkit.rb', line 256

def rotate(path, degrees:, pages: :all)
  Pdf::Loader.load!
  norm = Integer(degrees) % 360
  raise Error, 'degrees must be a multiple of 90' unless (norm % 90).zero?

  doc     = HexaPDF::Document.open(path)
  targets = resolve_pages(doc, pages)
  targets.each { |pg| pg[:Rotate] = ((pg[:Rotate] || 0).to_i + norm) % 360 }

  Result.new(bytes: write(doc), meta: { pages: doc.pages.count, rotated: targets.size, degrees: norm })
rescue HexaPDF::Error => e
  raise Error, "Rotate failed: #{e.message}"
end

.select_pages(path, pages:) ⇒ Result

Build a new PDF from an ordered list of page numbers to keep. Covers
extraction (a subset), deletion (omit pages), and reordering (permute).

Parameters:

  • path (String)
  • pages (Array<Integer>) —

    ordered, 1-based

Returns:



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# File 'app/services/pdf/toolkit.rb', line 277

def select_pages(path, pages:)
  Pdf::Loader.load!
  src   = HexaPDF::Document.open(path)
  count = src.pages.count
  order = Array(pages).map { |i| Integer(i) }
  raise Error, 'pages must be a non-empty list of page numbers' if order.empty?

  order.each { |i| raise Error, "page #{i} out of range (1-#{count})" if i < 1 || i > count }

  target = HexaPDF::Document.new
  order.each { |i| target.pages << target.import(src.pages[i - 1]) }

  Result.new(bytes: write(target), meta: { pages: order.size, kept: order })
rescue HexaPDF::Error => e
  raise Error, "Select pages failed: #{e.message}"
end

.split(path, ranges: nil) ⇒ Array<Result>

Explode a PDF into multiple documents. With no +ranges+, yields one
document per page. +ranges+ is an array of [start, end] (1-based, inclusive).

Parameters:

  • path (String)
  • ranges (Array<Array(Integer,Integer)>, nil) (defaults to: nil)

Returns:



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# File 'app/services/pdf/toolkit.rb', line 230

def split(path, ranges: nil)
  Pdf::Loader.load!
  src   = HexaPDF::Document.open(path)
  count = src.pages.count
  specs = ranges.presence || (1..count).map { |i| [i, i] }

  specs.map do |(a, b)|
    a = Integer(a)
    b = Integer(b || a)
    raise Error, "range #{a}-#{b} out of bounds (document has #{count} pages)" if a < 1 || b > count || a > b

    target = HexaPDF::Document.new
    (a..b).each { |i| target.pages << target.import(src.pages[i - 1]) }
    Result.new(bytes: write(target), meta: { pages: b - a + 1, range: [a, b] })
  end
rescue HexaPDF::Error => e
  raise Error, "Split failed: #{e.message}"
end

.stamp(path, operations:, pages: :all) ⇒ Result

Draw overlay operations on top of existing page content. Each operation
is a Hash with a +:type+ of "text", "cover", "image", or "watermark".
Operations are applied in order to every target page.

Parameters:

  • path (String)
  • operations (Array<Hash>) —

    ordered overlay ops

  • pages (:all, Integer, Array<Integer>) (defaults to: :all) —

    1-based target pages

Returns:



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# File 'app/services/pdf/toolkit.rb', line 138

def stamp(path, operations:, pages: :all)
  Pdf::Loader.load!
  raise Error, 'operations must be a non-empty array' unless operations.is_a?(Array) && operations.any?

  doc     = HexaPDF::Document.open(path)
  targets = resolve_pages(doc, pages)
  targets.each do |page|
    canvas = page.canvas(type: :overlay)
    mb     = page.box(:media)
    operations.each { |op| apply_op(doc, canvas, mb, symbolize(op)) }
  end

  Result.new(bytes: write(doc),
             meta: { pages: doc.pages.count, operations: operations.size, target_pages: targets.size })
rescue HexaPDF::Error => e
  raise Error, "Stamp failed: #{e.message}"
end