Make changelog match new shipping method (#137)

I forgot about this one on !136 😅️

Also, fix #134. And I think you may close #108, as I'm writing and testing using Linuxbrew.

Co-authored-by: Marcos de Oliveira <markinholiveira@gmail.com>
Reviewed-on: https://gitea.com/gitea/homebrew-gitea/pulls/137
Reviewed-by: Andrew Thornton <art27@cantab.net>
Reviewed-by: Lunny Xiao <xiaolunwen@gmail.com>
Co-authored-by: markkrj <markkrj@noreply.gitea.io>
Co-committed-by: markkrj <markkrj@noreply.gitea.io>

changelog.rb

@@ -1,46 +1,31 @@
-require "formula"
-
 class Changelog < Formula
+  desc "Generate changelog of gitea repository"
   homepage "https://gitea.com/gitea/changelog"
-  head "https://gitea.com/gitea/changelog.git"
+  version "master"
 
-  stable do
-    version "0.1.0"
-    url "https://dl.gitea.io/changelog-tool/#{version}/changelog-#{version}-darwin-10.6-amd64"
-    sha256 `curl -s https://dl.gitea.io/changelog-tool/#{version}/changelog-#{version}-darwin-10.6-amd64.sha256`.split(" ").first
-  end
+  os = OS.mac? ? "darwin-10.6" : "linux"
+  arch = case Hardware::CPU.arch
+         when :i386 then "386"
+         when :x86_64 then "amd64"
+         when :arm64 then "arm64"
+         else
+           raise "changelog: Unsupported system architecture #{Hardware::CPU.arch}"
+         end
 
-  head do
-    url "https://dl.gitea.io/changelog-tool/master/changelog-master-darwin-10.6-amd64"
-    sha256 `curl -s https://dl.gitea.io/changelog-tool/master/changelog-master-darwin-10.6-amd64.sha256`.split(" ").first
-    version "master"
-  end
+  @@filename = "changelog-#{version}-#{os}-#{arch}"
+  @@url = "https://dl.gitea.io/changelog-tool/#{version}/#{@@filename}.xz"
+  @@sha256 = %x[ curl -sL #{@@url}.sha256 ].split.first
 
-  head do
-    url "https://gitea.com/gitea/changelog.git", :branch => "master"
-    depends_on "go" => :build
+  url @@url
+  sha256 @@sha256
+
+  bottle :unneeded
+  def install
+    filename = Changelog.class_variable_get("@@filename")
+    bin.install filename => "changelog"
   end
 
   test do
     system "#{bin}/changelog", "--version"
   end
-
-  def install
-    case
-    when build.head?
-      mkdir_p buildpath/File.join("src", "code.gitea.io")
-      ln_s buildpath, buildpath/File.join("src", "code.gitea.io", "changelog")
-
-      ENV.append_path "PATH", File.join(buildpath, "bin")
-
-      ENV["GOPATH"] = buildpath
-      ENV["GOHOME"] = buildpath
-
-      system "cd src/code.gitea.io/changelog && make build"
-
-      bin.install "#{buildpath}/changelog" => "changelog"
-    else
-      bin.install "#{buildpath}/changelog-#{version}-darwin-10.6-amd64" => "changelog"
-    end
-  end
 end