add contain, cover & lots of refactoring

lib/image_plug.ex

@@ -12,7 +12,7 @@ defmodule ImagePlug do
   @type imgp_pixels() :: {:pixels, imgp_number()}
   @type imgp_pct() :: {:percent, imgp_number()}
   @type imgp_scale() :: {:scale, imgp_number(), imgp_number()}
-  @type imgp_ratio() :: {:ratio, imgp_number(), imgp_number()}
+  @type imgp_ratio() :: {imgp_number(), imgp_number()}
   @type imgp_length() :: imgp_pixels() | imgp_pct() | imgp_scale()
 
   @alpha_format_priority ~w(image/avif image/webp image/png)

lib/image_plug/param_parser/twicpics.ex

@@ -12,9 +12,36 @@ defmodule ImagePlug.ParamParser.Twicpics do
     "resize" => {ImagePlug.Transform.Scale, Twicpics.Transform.ScaleParser},
     "focus" => {ImagePlug.Transform.Focus, Twicpics.Transform.FocusParser},
     "contain" => {ImagePlug.Transform.Contain, Twicpics.Transform.ContainParser},
+    "contain-min" => {ImagePlug.Transform.Contain, Twicpics.Transform.ContainMinParser},
+    "contain-max" => {ImagePlug.Transform.Contain, Twicpics.Transform.ContainMaxParser},
+    "cover" => {ImagePlug.Transform.Cover, Twicpics.Transform.CoverParser},
+    "cover-min" => {ImagePlug.Transform.Cover, Twicpics.Transform.CoverMinParser},
+    "cover-max" => {ImagePlug.Transform.Cover, Twicpics.Transform.CoverMaxParser},
     "output" => {ImagePlug.Transform.Output, Twicpics.Transform.OutputParser}
   }
 
+  @shadowable_transforms ~w(resize cover focus output)
+
+  # consecutive transforms that can safely be shadowed
+  # e.g. two consecutive scale operations will only keep the last one
+  defp shadow_transforms(transform_kvs) do
+    Enum.reduce(transform_kvs, [], fn
+      transform, [] ->
+        [transform]
+
+      {key, _, _} = new, [{prev_key, _, _} | tail] = acc when key == prev_key ->
+        if Enum.member?(@shadowable_transforms, key) do
+          [new | tail]
+        else
+          [new | acc]
+        end
+
+      elem, acc ->
+        [elem | acc]
+    end)
+    |> Enum.reverse()
+  end
+
   @transform_keys Map.keys(@transforms)
   @query_param "twic"
   @query_param_prefix "v1/"
@@ -53,12 +80,12 @@ defmodule ImagePlug.ParamParser.Twicpics do
           {transform_name, params_str, key_start_pos}, {:ok, transforms_acc} ->
             {transform_mod, parser_mod} = Map.get(@transforms, transform_name)
 
-            # key start pos + key length + 1 (=-sign)
+            # key start pos + key length + 1 (the = char)
             value_pos = key_start_pos + String.length(transform_name) + 1
 
             case parser_mod.parse(params_str, value_pos) do
               {:ok, parsed_params} ->
-                {:cont, {:ok, [{transform_mod, parsed_params} | transforms_acc]}}
+                {:cont, {:ok, [{transform_name, transform_mod, parsed_params} | transforms_acc]}}
 
               {:error, _reason} = error ->
                 {:halt, error}
@@ -69,8 +96,15 @@ defmodule ImagePlug.ParamParser.Twicpics do
         error
     end
     |> case do
-      {:ok, transforms} -> {:ok, Enum.reverse(transforms)}
-      other -> other
+      {:ok, transforms} ->
+        {:ok,
+         transforms
+         |> Enum.reverse()
+         |> shadow_transforms()
+         |> Enum.map(fn {_name, mod, params} -> {mod, params} end)}
+
+      other ->
+        other
     end
   end
 

lib/image_plug/param_parser/twicpics/transform/contain_max_parser.ex

@@ -0,0 +1,28 @@
+defmodule ImagePlug.ParamParser.Twicpics.Transform.ContainMaxParser do
+  alias ImagePlug.ParamParser.Twicpics.SizeParser
+  alias ImagePlug.ParamParser.Twicpics.RatioParser
+  alias ImagePlug.ParamParser.Twicpics.Utils
+  alias ImagePlug.Transform.Contain.ContainParams
+
+  @doc """
+  Parses a string into a `ImagePlug.Transform.Contain.ContainParams` struct.
+
+  Syntax:
+  * `contain-max=<size>`
+
+  ## Examples
+
+      iex> ImagePlug.ParamParser.Twicpics.Transform.ContainMaxParser.parse("250x25.5")
+      {:ok, %ImagePlug.Transform.Contain.ContainParams{width: {:pixels, 250}, height: {:pixels, 25.5}, constraint: :max}}
+  """
+
+  def parse(input, pos_offset \\ 0) do
+    case SizeParser.parse(input, pos_offset) do
+      {:ok, %{width: width, height: height}} ->
+        {:ok, %ContainParams{width: width, height: height, constraint: :max}}
+
+      {:error, _reason} = error ->
+        Utils.update_error_input(error, input)
+    end
+  end
+end

lib/image_plug/param_parser/twicpics/transform/contain_min_parser.ex

@@ -0,0 +1,28 @@
+defmodule ImagePlug.ParamParser.Twicpics.Transform.ContainMinParser do
+  alias ImagePlug.ParamParser.Twicpics.SizeParser
+  alias ImagePlug.ParamParser.Twicpics.RatioParser
+  alias ImagePlug.ParamParser.Twicpics.Utils
+  alias ImagePlug.Transform.Contain.ContainParams
+
+  @doc """
+  Parses a string into a `ImagePlug.Transform.Contain.ContainParams` struct.
+
+  Syntax:
+  * `contain-min=<size>`
+
+  ## Examples
+
+      iex> ImagePlug.ParamParser.Twicpics.Transform.ContainMinParser.parse("250x25.5")
+      {:ok, %ImagePlug.Transform.Contain.ContainParams{width: {:pixels, 250}, height: {:pixels, 25.5}, constraint: :min}}
+  """
+
+  def parse(input, pos_offset \\ 0) do
+    case SizeParser.parse(input, pos_offset) do
+      {:ok, %{width: width, height: height}} ->
+        {:ok, %ContainParams{width: width, height: height, constraint: :min}}
+
+      {:error, _reason} = error ->
+        Utils.update_error_input(error, input)
+    end
+  end
+end

lib/image_plug/param_parser/twicpics/transform/contain_parser.ex

@@ -11,14 +11,15 @@ defmodule ImagePlug.ParamParser.Twicpics.Transform.ContainParser do
   * `contain=<size>`
 
   ## Examples
-      iex> ImagePlug.ParamParser.Twicpics.Transform.ContainParser.parse("250x25.5")
-      {:ok, %ImagePlug.Transform.Contain.ContainParams{width: {:pixels, 250}, height: {:pixels, 25.5}}}
+
+      iex> ImagePlug.ParamParser.Twicpics.Transform.ContainParser.parse("250x25.5p")
+      {:ok, %ImagePlug.Transform.Contain.ContainParams{width: {:pixels, 250}, height: {:percent, 25.5}, constraint: :none}}
   """
 
   def parse(input, pos_offset \\ 0) do
     case SizeParser.parse(input, pos_offset) do
       {:ok, %{width: width, height: height}} ->
-        {:ok, %ContainParams{width: width, height: height}}
+        {:ok, %ContainParams{width: width, height: height, constraint: :none}}
 
       {:error, _reason} = error ->
         Utils.update_error_input(error, input)

lib/image_plug/param_parser/twicpics/transform/cover_max_parser.ex

@@ -0,0 +1,28 @@
+defmodule ImagePlug.ParamParser.Twicpics.Transform.CoverMaxParser do
+  alias ImagePlug.ParamParser.Twicpics.SizeParser
+  alias ImagePlug.ParamParser.Twicpics.RatioParser
+  alias ImagePlug.ParamParser.Twicpics.Utils
+  alias ImagePlug.Transform.Cover.CoverParams
+
+  @doc """
+  Parses a string into a `ImagePlug.Transform.Cover.CoverParams` struct.
+
+  Syntax:
+  * `cover-max=<size>`
+
+  ## Examples
+
+      iex> ImagePlug.ParamParser.Twicpics.Transform.CoverMaxParser.parse("250x25.5")
+      {:ok, %ImagePlug.Transform.Cover.CoverParams{width: {:pixels, 250}, height: {:pixels, 25.5}, constraint: :max}}
+  """
+
+  def parse(input, pos_offset \\ 0) do
+    case SizeParser.parse(input, pos_offset) do
+      {:ok, %{width: width, height: height}} ->
+        {:ok, %CoverParams{width: width, height: height, constraint: :max}}
+
+      {:error, _reason} = error ->
+        Utils.update_error_input(error, input)
+    end
+  end
+end

lib/image_plug/param_parser/twicpics/transform/cover_min_parser.ex

@@ -0,0 +1,28 @@
+defmodule ImagePlug.ParamParser.Twicpics.Transform.CoverMinParser do
+  alias ImagePlug.ParamParser.Twicpics.SizeParser
+  alias ImagePlug.ParamParser.Twicpics.RatioParser
+  alias ImagePlug.ParamParser.Twicpics.Utils
+  alias ImagePlug.Transform.Cover.CoverParams
+
+  @doc """
+  Parses a string into a `ImagePlug.Transform.Cover.CoverParams` struct.
+
+  Syntax:
+  * `cover-min=<size>`
+
+  ## Examples
+
+      iex> ImagePlug.ParamParser.Twicpics.Transform.CoverMinParser.parse("250x25.5")
+      {:ok, %ImagePlug.Transform.Cover.CoverParams{width: {:pixels, 250}, height: {:pixels, 25.5}, constraint: :min}}
+  """
+
+  def parse(input, pos_offset \\ 0) do
+    case SizeParser.parse(input, pos_offset) do
+      {:ok, %{width: width, height: height}} ->
+        {:ok, %CoverParams{width: width, height: height, constraint: :min}}
+
+      {:error, _reason} = error ->
+        Utils.update_error_input(error, input)
+    end
+  end
+end

lib/image_plug/param_parser/twicpics/transform/cover_parser.ex

@@ -0,0 +1,48 @@
+defmodule ImagePlug.ParamParser.Twicpics.Transform.CoverParser do
+  alias ImagePlug.ParamParser.Twicpics.SizeParser
+  alias ImagePlug.ParamParser.Twicpics.RatioParser
+  alias ImagePlug.ParamParser.Twicpics.Utils
+  alias ImagePlug.Transform.Cover.CoverParams
+
+  @doc """
+  Parses a string into a `ImagePlug.Transform.Cover.CoverParams` struct.
+
+  Syntax
+  * `cover=<size>`
+  * `cover=<ratio>`
+
+  ## Examples
+
+      iex> ImagePlug.ParamParser.Twicpics.Transform.CoverParser.parse("250x25.5")
+      {:ok, %ImagePlug.Transform.Cover.CoverParams{type: :dimensions, width: {:pixels, 250}, height: {:pixels, 25.5}, constraint: :none}}
+
+      iex> ImagePlug.ParamParser.Twicpics.Transform.CoverParser.parse("16:9")
+      {:ok, %ImagePlug.Transform.Cover.CoverParams{type: :ratio, ratio: {16, 9}}}
+  """
+
+  def parse(input, pos_offset \\ 0) do
+    if String.contains?(input, ":"),
+      do: parse_ratio(input, pos_offset),
+      else: parse_size(input, pos_offset)
+  end
+
+  defp parse_ratio(input, pos_offset) do
+    case RatioParser.parse(input, pos_offset) do
+      {:ok, %{width: width, height: height}} ->
+        {:ok, %CoverParams{type: :ratio, ratio: {width, height}}}
+
+      {:error, _reason} = error ->
+        Utils.update_error_input(error, input)
+    end
+  end
+
+  defp parse_size(input, pos_offset) do
+    case SizeParser.parse(input, pos_offset) do
+      {:ok, %{width: width, height: height}} ->
+        {:ok, %CoverParams{type: :dimensions, width: width, height: height, constraint: :none}}
+
+      {:error, _reason} = error ->
+        Utils.update_error_input(error, input)
+    end
+  end
+end

lib/image_plug/param_parser/twicpics/transform/scale_parser.ex

@@ -15,25 +15,25 @@ defmodule ImagePlug.ParamParser.Twicpics.Transform.ScaleParser do
 
   ## Examples
       iex> ImagePlug.ParamParser.Twicpics.Transform.ScaleParser.parse("250x25p")
-      {:ok, %ImagePlug.Transform.Scale.ScaleParams{method: %ImagePlug.Transform.Scale.ScaleParams.Dimensions{width: {:pixels, 250}, height: {:percent, 25}}}}
+      {:ok, %ImagePlug.Transform.Scale.ScaleParams{type: :dimensions, width: {:pixels, 250}, height: {:percent, 25}}}
 
       iex> ImagePlug.ParamParser.Twicpics.Transform.ScaleParser.parse("-x25p")
-      {:ok, %ImagePlug.Transform.Scale.ScaleParams{method: %ImagePlug.Transform.Scale.ScaleParams.Dimensions{width: :auto, height: {:percent, 25}}}}
+      {:ok, %ImagePlug.Transform.Scale.ScaleParams{type: :dimensions, width: :auto, height: {:percent, 25}}}
 
       iex> ImagePlug.ParamParser.Twicpics.Transform.ScaleParser.parse("50.5px-")
-      {:ok, %ImagePlug.Transform.Scale.ScaleParams{method: %ImagePlug.Transform.Scale.ScaleParams.Dimensions{width: {:percent, 50.5}, height: :auto}}}
+      {:ok, %ImagePlug.Transform.Scale.ScaleParams{type: :dimensions, width: {:percent, 50.5}, height: :auto}}
 
       iex> ImagePlug.ParamParser.Twicpics.Transform.ScaleParser.parse("50.5")
-      {:ok, %ImagePlug.Transform.Scale.ScaleParams{method: %ImagePlug.Transform.Scale.ScaleParams.Dimensions{width: {:pixels, 50.5}, height: :auto}}}
+      {:ok, %ImagePlug.Transform.Scale.ScaleParams{type: :dimensions, width: {:pixels, 50.5}, height: :auto}}
 
       iex> ImagePlug.ParamParser.Twicpics.Transform.ScaleParser.parse("50p")
-      {:ok, %ImagePlug.Transform.Scale.ScaleParams{method: %ImagePlug.Transform.Scale.ScaleParams.Dimensions{width: {:percent, 50}, height: :auto}}}
+      {:ok, %ImagePlug.Transform.Scale.ScaleParams{type: :dimensions, width: {:percent, 50}, height: :auto}}
 
       iex> ImagePlug.ParamParser.Twicpics.Transform.ScaleParser.parse("(25*10)x(1/2)s")
-      {:ok, %ImagePlug.Transform.Scale.ScaleParams{method: %ImagePlug.Transform.Scale.ScaleParams.Dimensions{width: {:pixels, 250}, height: {:scale, 0.5}}}}
+      {:ok, %ImagePlug.Transform.Scale.ScaleParams{type: :dimensions, width: {:pixels, 250}, height: {:scale, 0.5}}}
 
       iex> ImagePlug.ParamParser.Twicpics.Transform.ScaleParser.parse("16:9")
-      {:ok, %ImagePlug.Transform.Scale.ScaleParams{method: %ImagePlug.Transform.Scale.ScaleParams.AspectRatio{aspect_ratio: {:ratio, 16, 9}}}}
+      {:ok, %ImagePlug.Transform.Scale.ScaleParams{type: :ratio, ratio: {16, 9}}}
   """
   def parse(input, pos_offset \\ 0) do
     if String.contains?(input, ":"),
@@ -44,7 +44,7 @@ defmodule ImagePlug.ParamParser.Twicpics.Transform.ScaleParser do
   defp parse_ratio(input, pos_offset) do
     case RatioParser.parse(input, pos_offset) do
       {:ok, %{width: width, height: height}} ->
-        {:ok, %ScaleParams{method: %AspectRatio{aspect_ratio: {:ratio, width, height}}}}
+        {:ok, %ScaleParams{type: :ratio, ratio: {width, height}}}
 
       {:error, _reason} = error ->
         Utils.update_error_input(error, input)
@@ -54,7 +54,7 @@ defmodule ImagePlug.ParamParser.Twicpics.Transform.ScaleParser do
   defp parse_size(input, pos_offset) do
     case SizeParser.parse(input, pos_offset) do
       {:ok, %{width: width, height: height}} ->
-        {:ok, %ScaleParams{method: %Dimensions{width: width, height: height}}}
+        {:ok, %ScaleParams{type: :dimensions, width: width, height: height}}
 
       {:error, _reason} = error ->
         Utils.update_error_input(error, input)

lib/image_plug/transform.ex

@@ -3,23 +3,4 @@ defmodule ImagePlug.Transform do
   alias ImagePlug.ArithmeticParser
 
   @callback execute(TransformState.t(), String.t()) :: TransformState.t()
-
-  def image_dim(%TransformState{image: image}, :width), do: Image.width(image)
-  def image_dim(%TransformState{image: image}, :height), do: Image.height(image)
-
-  @spec to_pixels(TransformState.t(), :width | :height, ImagePlug.imgp_length()) ::
-          {:ok, integer()} | {:error, atom()}
-  def to_pixels(state, dimension, length)
-
-  def to_pixels(_state, _dimension, {:pixels, num}) do
-    {:ok, round(num)}
-  end
-
-  def to_pixels(state, dimension, {:scale, numerator, denominator}) do
-    {:ok, round(image_dim(state, dimension) * numerator / denominator)}
-  end
-
-  def to_pixels(state, dimension, {:percent, num}) do
-    {:ok, round(num / 100 * image_dim(state, dimension))}
-  end
 end