defmodule Torch.PaginationView do
use Phoenix.Component
use PhoenixHTMLHelpers
import Torch.I18n, only: [message: 1]
alias Torch.TableView
@doc """
Render pagination links directly from a `Plug.Conn`
"""
def pagination(conn) do
assigns =
%{__changed__: %{}}
|> Map.merge(conn.assigns)
|> assign(:query_string, conn.query_string)
|> assign(:sort_opts, sort_opts(conn.assigns))
|> assign(:conn_params, conn.params)
~H"""
<.torch_pagination page_number={@page_number} page_size={@page_size} total_pages={@total_pages} total_entries={@total_entries} distance={@distance} sort_field={@sort_field} sort_direction={@sort_direction} query_string={@query_string} conn_params={@conn_params} />
"""
end
@doc """
Render Torch pagination links based on current page, sort, and filters
"""
@doc since: "5.0.0"
attr(:page_number, :integer, required: true)
attr(:page_size, :integer, required: true)
attr(:total_pages, :integer, required: true)
attr(:total_entries, :integer, required: true)
attr(:distance, :integer, required: false)
attr(:sort_field, :string, required: false)
attr(:sort_direction, :string, required: false)
attr(:query_string, :string, required: true)
attr(:conn_params, :map, required: true)
def torch_pagination(assigns) do
assigns =
assigns
|> assign_new(:distance, fn -> 5 end)
|> assign(
:new_querystring,
fn p ->
TableView.querystring(assigns.query_string, assigns.conn_params, %{
page: p
})
end
)
~H"""
<section id="torch-pagination">
<ul>
<li><.prev_link page_number={@page_number} query_string={@query_string} conn_params={@conn_params} /></li>
<%= if @total_pages > 1 do %>
<%= for num <- start_page(@page_number, @distance)..end_page(@page_number, @total_pages, @distance) do %>
<li>
<.page_link page_number={num} is_active={@page_number == num} query_string={@query_string} conn_params={@conn_params} />
</li>
<% end %>
<% end %>
<li><.next_link page_number={@page_number} total_pages={@total_pages} query_string={@query_string} conn_params={@conn_params} /></li>
</ul>
</section>
"""
end
@doc """
Generates a "_N_" link to a page of results (where N is the page number).
## Examples
iex> a = %{__changed__: %{}, query_string: "", conn_params: %{page: 1}, page_number: 14}
...> page_link(a) |> Phoenix.HTML.Safe.to_iodata() |> IO.iodata_to_binary()
"<a href=\\"?page=14\\" class=\\"\\">14</a>"
It will also allow customizing of the "active" link:
iex> a = %{__changed__: %{}, query_string: "", conn_params: %{page: 1}, page_number: 14, is_active: true}
...> page_link(a) |> Phoenix.HTML.Safe.to_iodata() |> IO.iodata_to_binary()
"<a href=\\"?page=14\\" class=\\"active\\">14</a>"
"""
@doc since: "5.0.0"
attr(:query_string, :string, default: "")
attr(:conn_params, :any, required: true)
attr(:page_number, :integer, required: true)
attr(:is_active, :boolean, default: false)
def page_link(
%{
__changed__: _,
query_string: qs,
conn_params: params,
page_number: pn
} = assigns
)
when is_integer(pn) and pn > 0 do
assigns =
assigns
|> assign(
:new_querystring,
TableView.querystring(qs, params, %{page: pn})
)
~H"""
<a href={"?#{@new_querystring}"} class={if @is_active, do: "active", else: ""}><%= @page_number %></a>
"""
end
def page_link(assigns) do
~H"""
"""
end
@doc """
Generates a "< Prev" link to the previous page of results.
The link is only returned if there is a previous page.
## Examples
iex> a = %{__changed__: nil, query_string: "", conn_params: %{page: 3}, page_number: 3}
...> prev_link(a) |> Phoenix.HTML.Safe.to_iodata() |> IO.iodata_to_binary()
"<a href=\\"?page=2\\">< Prev</a>"
If the current page is 1, returns an empty string:
iex> a = %{__changed__: nil, query_string: "", conn_params: %{page: 1}, page_number: 1}
...> prev_link(a) |> Phoenix.HTML.Safe.to_iodata() |> IO.iodata_to_binary()
""
"""
# NOTE: query_string param can contain sort info also (e.g. sort_field=name&sort_direction=asc)
@doc since: "5.0.0"
attr(:query_string, :string, default: "")
attr(:conn_params, :any, required: true)
attr(:page_number, :integer, required: true)
def prev_link(
%{__changed__: _, query_string: qs, conn_params: params, page_number: pn} = assigns
)
when is_integer(pn) and pn > 1 do
assigns =
assign(
assigns,
:new_querystring,
TableView.querystring(qs, params, %{page: pn - 1})
)
~H"""
<a href={"?#{@new_querystring}"}><%= message("< Prev") %></a>
"""
end
def prev_link(%{__changed__: _, query_string: _, conn_params: _, page_number: _} = assigns) do
~H"""
"""
end
def prev_link(%{__changed__: _changed, query_string: _qs, page_number: _pn} = assigns) do
assigns
|> assign(:conn_params, %{})
|> prev_link()
end
def prev_link(%{__changed__: _changed, query_string: _qs, conn_params: _p} = assigns) do
assigns
|> assign(:page_number, 1)
|> prev_link()
end
def prev_link(%{__changed__: _changed, query_string: _qs} = assigns) do
assigns
|> assign(:page_number, 1)
|> assign(:conn_params, %{})
|> prev_link()
end
@doc """
Generates a "Next >" link to the next page of results.
The link is only returned if there is another page.
## Examples
iex> a = %{__changed__: nil, query_string: "", conn_params: %{page: 2}, page_number: 2, total_pages: 4}
...> next_link(a) |> Phoenix.HTML.Safe.to_iodata() |> IO.iodata_to_binary()
"<a href=\\"?page=3\\">Next ></a>"
If there is no available next page, returns an empty string:
iex> a = %{__changed__: nil, query_string: "", conn_params: %{page: 2}, page_number: 2, total_pages: 2}
...> next_link(a) |> Phoenix.HTML.Safe.to_iodata() |> IO.iodata_to_binary()
""
"""
@doc since: "5.0.0"
attr(:query_string, :string, default: "")
attr(:conn_params, :any, required: true)
attr(:page_number, :integer, required: true)
attr(:total_pages, :integer, required: true)
def next_link(
%{
__changed__: _,
query_string: qs,
conn_params: params,
page_number: page_number,
total_pages: total_pages
} = assigns
)
when is_integer(page_number) and is_integer(total_pages) and page_number < total_pages do
assigns =
assign(
assigns,
:new_querystring,
TableView.querystring(qs, params, %{page: page_number + 1})
)
~H"""
<a href={"?#{@new_querystring}"}><%= message("Next >") %></a>
"""
end
def next_link(
%{
__changed__: _,
query_string: _qs,
conn_params: _params,
page_number: _page_number,
total_pages: _total_pages
} = assigns
) do
~H"""
"""
end
def next_link(
%{
__changed__: _,
query_string: _,
page_number: _,
total_pages: _
} = assigns
) do
assigns
|> assign(:conn_params, %{})
|> next_link()
end
def next_link(
%{
__changed__: _,
query_string: _,
conn_params: _,
total_pages: _
} = assigns
) do
assigns
|> assign(:page_number, 1)
|> next_link()
end
def next_link(
%{
__changed__: _,
query_string: _,
conn_params: _,
page_number: pn
} = assigns
) do
assigns
|> assign(:total_pages, pn)
|> next_link()
end
def next_link(
%{
__changed__: _,
query_string: _
} = assigns
) do
assigns
|> assign(:conn_params, %{})
|> assign(:page_number, 1)
|> assign(:total_pages, 1)
|> next_link()
end
defp start_page(current_page, distance)
when current_page - distance <= 0 do
1
end
defp start_page(current_page, distance) do
current_page - distance
end
defp end_page(current_page, 0, _distance) do
current_page
end
defp end_page(current_page, total, distance)
when current_page <= distance and distance * 2 <= total do
distance * 2
end
defp end_page(current_page, total, distance) when current_page + distance >= total do
total
end
defp end_page(current_page, _total, distance) do
current_page + distance - 1
end
defp sort_opts(%{sort_field: sort_field, sort_direction: sort_direction}) do
%{sort_field: sort_field, sort_direction: sort_direction}
end
end
