Images

The previous work in xou#124 by x and x
was using a twoCellAnchor but that's quite tricky
to get right.

This is now using a oneCellAnchor to make the
calculations much simpler.

I have added a few extra tests.

I also fixed the formula because I couldn't run
the example file without doing that first.

.gitignore

@@ -31,3 +31,6 @@ elixlsx-*.tar
 
 # Misc.
 *.swp
+
+# Elixir LS cache
+/.elixir_ls/

example.exs

@@ -4,7 +4,8 @@ require Elixlsx
 
 alias Elixlsx.{Sheet, Workbook}
 
-sheet1 = Sheet.with_name("First")
+sheet1 =
+  Sheet.with_name("First")
   # Set cell B2 to the string "Hi". :)
   |> Sheet.set_cell("B2", "Hi")
   # Optionally, set font properties:
@@ -48,11 +49,15 @@ sheet1 = Sheet.with_name("First")
   |> Sheet.set_cell("A3", "cow")
   |> Sheet.add_data_validations("A1", "A10", ["dog", "cat", "cow"])
   # within same sheet
-  |> Sheet.add_data_validations("A1", "A10", "=$A$2:$A$16")
+  |> Sheet.add_data_validations("B1", "B10", "=$B$2:$B$16")
   # reference to other sheet  "=#{sheet.name}!$A$2:$A$16"
-  |> Sheet.add_data_validations("A1", "A10", "=sheet2!$A$2:$A$16")
+  |> Sheet.add_data_validations("C1", "C10", "=Third!$A$2:$A$16")
 
-workbook = %Workbook{sheets: [sheet1]}
+workbook = %Workbook{
+  sheets: [sheet1],
+  font: "Arial",
+  font_size: 12
+}
 
 # it is also possible to add a custom "created" date to workbook, otherwise,
 # the current date is used.
@@ -65,7 +70,7 @@ sheet2 =
     name: "Third",
     rows: [[1, 2, 3, 4, 5], [1, 2], ["increased row height"], ["hello", "world"]]
   }
-  |> Sheet.set_row_height(3, 40)
+  |> Sheet.set_row_height(2, 75)
 
 workbook = Workbook.append_sheet(workbook, sheet2)
 
@@ -136,7 +141,7 @@ sheet5 =
 sheet6 =
   %Sheet{
     name: "Row and Column Groups",
-    rows: 1..100 |> Enum.chunk(10),
+    rows: 1..100 |> Enum.chunk_every(10),
     # collapse and hide rows 2 to 3
     group_rows: [{2..3, collapsed: true}, 6..7],
     # nest
@@ -145,7 +150,55 @@ sheet6 =
   # nest further
   |> Sheet.group_cols("C", "D")
 
+# Images
+sheet7 = %Sheet{
+  name: "Images",
+  rows: List.duplicate(["A", "B", "C", "D", "E"], 5)
+}
+
+sheet7 =
+  sheet7
+  |> Sheet.set_col_width("A", 10)
+  |> Sheet.set_col_width("B", 10)
+  |> Sheet.set_col_width("C", 10)
+  |> Sheet.set_col_width("D", 10)
+  |> Sheet.set_col_width("E", 10)
+  |> Sheet.set_row_height(1, 75)
+  |> Sheet.set_row_height(2, 75)
+  |> Sheet.set_row_height(3, 75)
+  |> Sheet.set_row_height(4, 75)
+  |> Sheet.set_row_height(5, 75)
+  |> Sheet.insert_image(1, 1, "ladybug-3475779_640.jpg", width: 50, height: 50, align_x: :right, char: 9)
+  |> Sheet.insert_image(2, 2, "ladybug-3475779_640.jpg", width: 100, height: 100)
+  |> Sheet.insert_image(3, 0, {"ladybug-3475779_640.jpg", File.read!("ladybug-3475779_640.jpg")}, width: 150, height: 150)
+
+sheet8 = %Sheet{
+  name: "Images 2",
+  rows: List.duplicate(["A", "B", "C", "D", "E"], 5)
+}
+
+sheet8 =
+  sheet8
+  |> Sheet.set_col_width("A", 10)
+  |> Sheet.set_col_width("B", 10)
+  |> Sheet.set_col_width("C", 10)
+  |> Sheet.set_col_width("D", 10)
+  |> Sheet.set_col_width("E", 10)
+  |> Sheet.set_row_height(1, 75)
+  |> Sheet.set_row_height(2, 75)
+  |> Sheet.set_row_height(3, 75)
+  |> Sheet.set_row_height(4, 75)
+  |> Sheet.set_row_height(5, 75)
+  |> Sheet.insert_image(0, 0, "ladybug-3475779_640.jpg",
+    width: 100,
+    height: 100,
+    x_offset: 50,
+    y_offset: 50
+  )
+
 Workbook.append_sheet(workbook, sheet4)
 |> Workbook.append_sheet(sheet5)
 |> Workbook.append_sheet(sheet6)
+|> Workbook.append_sheet(sheet7)
+|> Workbook.append_sheet(sheet8)
 |> Elixlsx.write_to("example.xlsx")

lib/elixlsx/compiler.ex

@@ -1,7 +1,9 @@
 defmodule Elixlsx.Compiler do
   alias Elixlsx.Compiler.WorkbookCompInfo
   alias Elixlsx.Compiler.SheetCompInfo
+  alias Elixlsx.Compiler.DrawingCompInfo
   alias Elixlsx.Compiler.CellStyleDB
+  alias Elixlsx.Compiler.DrawingDB
   alias Elixlsx.Compiler.StringDB
   alias Elixlsx.XML
   alias Elixlsx.Sheet
@@ -25,6 +27,26 @@ defmodule Elixlsx.Compiler do
     {Enum.reverse(sheetCompInfos), nextrID}
   end
 
+  @doc """
+  Turn a list of %Sheet{} into a list of %DrawingCompInfo{}
+  and return the next rId after.
+  """
+  @spec make_drawing_info(nonempty_list(Sheet.t()), non_neg_integer) ::
+          {list(DrawingCompInfo.t()), non_neg_integer}
+  def make_drawing_info(sheets, init_rId) do
+    {dcis, _, next_id} =
+      Enum.reduce(sheets, {[], 1, init_rId}, fn acc, {dci, idx, rId} ->
+        if acc.images == [] do
+          {dci, idx, rId}
+        else
+          new_dci = DrawingCompInfo.make(idx, rId)
+          {dci ++ [new_dci], idx + 1, rId + 1}
+        end
+      end)
+
+    {dcis, next_id}
+  end
+
   def compinfo_cell_pass_value(wci, value) do
     cond do
       is_binary(value) && XML.valid?(value) ->
@@ -59,6 +81,16 @@ defmodule Elixlsx.Compiler do
     end
   end
 
+  def compinfo_image_pass(wci, image) do
+    update_in(wci.drawingdb, &DrawingDB.register_image(&1, image))
+  end
+
+  def compinfo_from_images(wci, images) do
+    List.foldl(images, wci, fn image, wci ->
+      compinfo_image_pass(wci, image)
+    end)
+  end
+
   @spec compinfo_from_rows(WorkbookCompInfo.t(), list(list(any()))) :: WorkbookCompInfo.t()
   def compinfo_from_rows(wci, rows) do
     List.foldl(rows, wci, fn cols, wci ->
@@ -71,16 +103,20 @@ defmodule Elixlsx.Compiler do
   @spec compinfo_from_sheets(WorkbookCompInfo.t(), list(Sheet.t())) :: WorkbookCompInfo.t()
   def compinfo_from_sheets(wci, sheets) do
     List.foldl(sheets, wci, fn sheet, wci ->
-      compinfo_from_rows(wci, sheet.rows)
+      wci
+      |> compinfo_from_rows(sheet.rows)
+      |> compinfo_from_images(sheet.images)
     end)
   end
 
   @first_free_rid 2
   def make_workbook_comp_info(workbook) do
     {sci, next_rId} = make_sheet_info(workbook.sheets, @first_free_rid)
+    {dci, next_rId} = make_drawing_info(workbook.sheets, next_rId)
 
     %WorkbookCompInfo{
       sheet_info: sci,
+      drawing_info: dci,
       next_free_xl_rid: next_rId
     }
     |> compinfo_from_sheets(workbook.sheets)

lib/elixlsx/compiler/drawing_comp_info.ex

@@ -0,0 +1,27 @@
+defmodule Elixlsx.Compiler.DrawingCompInfo do
+  alias __MODULE__
+
+  @moduledoc ~S"""
+  Compilation info for a Drawing, to be filled
+  during the actual write process.
+  """
+
+  defstruct rId: "",
+            filename: "drawing1.xml",
+            drawingId: 0
+
+  @type t :: %DrawingCompInfo{
+          rId: String.t(),
+          filename: String.t(),
+          drawingId: non_neg_integer
+        }
+
+  @spec make(non_neg_integer, non_neg_integer) :: DrawingCompInfo.t()
+  def make(drawingidx, rId) do
+    %DrawingCompInfo{
+      rId: "rId" <> to_string(rId),
+      filename: "drawing" <> to_string(drawingidx) <> ".xml",
+      drawingId: drawingidx
+    }
+  end
+end

lib/elixlsx/compiler/drawing_db.ex

@@ -0,0 +1,49 @@
+defmodule Elixlsx.Compiler.DrawingDB do
+  alias __MODULE__
+  alias Elixlsx.Image
+
+  @moduledoc ~S"""
+  Database of drawing elements in the whole document.
+
+  Drawing id values must be unique across the document
+  regardless of what kind of drawing they are.
+  """
+
+  defstruct images: %{}, element_count: 0
+
+  @type t :: %DrawingDB{
+          images: %{Image.t() => pos_integer},
+          element_count: non_neg_integer
+        }
+
+  def register_image(drawingdb, image) do
+    case Map.fetch(drawingdb.images, image) do
+      :error ->
+        %DrawingDB{
+          images: Map.put(drawingdb.images, image, drawingdb.element_count + 1),
+          element_count: drawingdb.element_count + 1
+        }
+
+      {:ok, _} ->
+        drawingdb
+    end
+  end
+
+  def get_id(drawingdb, image) do
+    case Map.fetch(drawingdb.images, image) do
+      :error ->
+        raise %ArgumentError{
+          message: "Invalid key provided for DrawingDB.get_id: " <> inspect(image)
+        }
+
+      {:ok, id} ->
+        id
+    end
+  end
+
+  def image_types(db) do
+    db.images
+    |> Enum.map(fn {i, _} -> {i.extension, i.type} end)
+    |> Enum.uniq()
+  end
+end

lib/elixlsx/compiler/workbook_comp_info.ex

@@ -6,25 +6,29 @@ defmodule Elixlsx.Compiler.WorkbookCompInfo do
   required to generate the XML file.
 
   It is used as the aggregator when folding over the individual
-  cells.
+  cells and images.
   """
   defstruct sheet_info: nil,
+            drawing_info: nil,
             stringdb: %Compiler.StringDB{},
             fontdb: %Compiler.FontDB{},
             filldb: %Compiler.FillDB{},
             cellstyledb: %Compiler.CellStyleDB{},
             numfmtdb: %Compiler.NumFmtDB{},
             borderstyledb: %Compiler.BorderStyleDB{},
+            drawingdb: %Compiler.DrawingDB{},
             next_free_xl_rid: nil
 
   @type t :: %Compiler.WorkbookCompInfo{
           sheet_info: [Compiler.SheetCompInfo.t()],
+          drawing_info: [Compiler.DrawingCompInfo.t()],
           stringdb: Compiler.StringDB.t(),
           fontdb: Compiler.FontDB.t(),
           filldb: Compiler.FillDB.t(),
           cellstyledb: Compiler.CellStyleDB.t(),
           numfmtdb: Compiler.NumFmtDB.t(),
           borderstyledb: Compiler.BorderStyleDB.t(),
+          drawingdb: Compiler.DrawingDB.t(),
           next_free_xl_rid: non_neg_integer
         }
 end

lib/elixlsx/image.ex

@@ -0,0 +1,77 @@
+defmodule Elixlsx.Image do
+  alias Elixlsx.Image
+
+  @moduledoc ~S"""
+  An Image can either by a path to an image, or
+  a binary {"path_or_unique_id", <<binary>>}
+
+  char is the max character width of a font, this is
+  used when calculating how many pixels are in a column.
+  You might need to experiment with this value
+  depending on what font and size you are using.
+  """
+
+  defstruct file_path: "",
+            type: "image/png",
+            extension: "png",
+            x: 0,
+            y: 0,
+            x_offset: 0,
+            y_offset: 0,
+            width: 1,
+            height: 1,
+            binary: nil,
+            align_x: :left,
+            char: 7
+
+  @type t :: %Image{
+          file_path: String.t() | {String.t(), binary},
+          type: String.t(),
+          extension: String.t(),
+          x: integer,
+          y: integer,
+          x_offset: integer,
+          y_offset: integer,
+          width: integer,
+          height: integer,
+          binary: binary | nil,
+          align_x: :left | :right,
+          char: integer
+        }
+
+  @doc """
+  Create an image struct based on opts
+  """
+  def new(_, _, _, opts \\ [])
+
+  def new(file_path, x, y, opts) when is_binary(file_path) do
+    new({file_path, nil}, x, y, opts)
+  end
+
+  def new({file_path, binary}, x, y, opts) do
+    {ext, type} = image_type(file_path)
+
+    %Image{
+      file_path: file_path,
+      binary: binary,
+      type: type,
+      extension: ext,
+      x: x,
+      y: y,
+      x_offset: Keyword.get(opts, :x_offset, 0),
+      y_offset: Keyword.get(opts, :y_offset, 0),
+      width: Keyword.get(opts, :width, 1),
+      height: Keyword.get(opts, :height, 1),
+      align_x: Keyword.get(opts, :align_x, :left),
+      char: Keyword.get(opts, :char, 7)
+    }
+  end
+
+  defp image_type(file_path) do
+    case Path.extname(file_path) do
+      ".jpg" -> {"jpg", "image/jpeg"}
+      ".jpeg" -> {"jpeg", "image/jpeg"}
+      ".png" -> {"png", "image/png"}
+    end
+  end
+end