add /guff/themes/ handler

3 files changed, 140 insertions, 3 deletions

diff --git a/src/guff/cli.cr b/src/guff/cli.cr
index 680e418..e5d8c6c 100644
--- a/src/guff/cli.cr
+++ b/src/guff/cli.cr
@@ -32,7 +32,7 @@ module Guff::CLI
       end
 
       # list of subdirectories to create in data directory
-      DIRS = %w{files themes cache/themes}
+      DIRS = %w{files themes cache/theme-files}
 
       def run
         # create data dir
diff --git a/src/guff/handlers.cr b/src/guff/handlers.cr
index a0cb335..efdf6e0 100644
--- a/src/guff/handlers.cr
+++ b/src/guff/handlers.cr
@@ -600,6 +600,73 @@ module Guff::Handlers
     end
   end
 
+  # FIXME: this is very similar to AssetsHandler, so maybe combine them?
+  class ThemesHandler < Handler
+    def call(context : HTTP::Server::Context)
+      req_path = context.request.path.not_nil!
+
+      if matching_request?(context.request.method, req_path) &&
+         true # valid_origin_headers?(context.request.headers)
+        # get expanded path to file
+        if abs_path = expand_path(req_path)
+          # get file digest
+          etag = ETag.get_file_etag(abs_path)
+
+          # check for cache header
+          if context.request.headers["if-none-match"]? == etag
+            # cached, send 304 not modified
+            context.response.status_code = 304
+          else
+            # not cached, set code and send headers
+            context.response.headers["x-frame-options"] = "SAMEORIGIN"
+            context.response.status_code = 200
+            context.response.content_type = @context.magic.file(abs_path)
+            context.response.content_length = File.size(abs_path)
+            context.response.headers["etag"] = etag
+
+            if context.request.method == "GET"
+              # send body for GET requests
+              File.open(abs_path) do |fh|
+                IO.copy(fh, context.response)
+              end
+            end
+          end
+        else
+          # expanded path does not exist
+          call_next(context)
+        end
+      else
+        # not a matching request
+        call_next(context)
+      end
+    end
+
+    VALID_METHODS = %w{GET HEAD}
+    PATH_RE = %r{^/guff/themes/[^/]+/[^/]+}
+
+    EXTRACT_RE = %r{^/guff/themes/(?<slug>[^/]+)/(?<path>.+)$}
+
+    private def matching_request?(method, path)
+      VALID_METHODS.includes?(method) && PATH_RE.match(path)
+    end
+
+    private def expand_path(req_path : String) : String?
+      # unescape path, check for nil byte
+      path = URI.unescape(req_path)
+      return nil if path.includes?('\0')
+
+      # get theme slug and file path
+      md = EXTRACT_RE.match(path)
+      return nil unless md
+
+      # map slug and file path to absolute path
+      @context.models.theme.get_file_path(
+        slug: md["slug"],
+        path: md["path"],
+      )
+    end
+  end
+
   # FIXME: this is very similar to FilesHandler and AssetsHandler, so
   # maybe combine them?
   class FileAPIHandler < AuthenticatedHandler
@@ -691,6 +758,9 @@ module Guff::Handlers
     :id   => :files,
   }, {
     :dev  => false,
+    :id   => :themes,
+  }, {
+    :dev  => false,
     :id   => :page,
   }, {
     :dev  => false,
@@ -768,6 +838,8 @@ module Guff::Handlers
       ProjectHandler.new(context)
     when :files
       FilesHandler.new(context)
+    when :themes
+      ThemesHandler.new(context)
     else
       raise "unknown handler id: #{handler_id}"
     end
diff --git a/src/guff/models/theme.cr b/src/guff/models/theme.cr
index 1e09727..e2eda39 100644
--- a/src/guff/models/theme.cr
+++ b/src/guff/models/theme.cr
@@ -3,6 +3,7 @@ class Guff::Models::ThemeModel < Guff::Models::Model
     all: "
       SELECT a.theme_id,
              a.theme_name,
+             a.theme_slug,
              a.theme_version,
              a.theme_date,
              a.is_system,
@@ -21,6 +22,7 @@ class Guff::Models::ThemeModel < Guff::Models::Model
 
     get: "
       SELECT a.theme_id,
+             a.theme_slug,
              a.theme_name,
              a.theme_version,
              a.theme_date,
@@ -35,7 +37,7 @@ class Guff::Models::ThemeModel < Guff::Models::Model
 
         FROM themes a
 
-       WHERE theme_id = ?
+       WHERE %s
     ",
 
     get_data: "
@@ -95,6 +97,17 @@ class Guff::Models::ThemeModel < Guff::Models::Model
         ?
       )
     ",
+
+    get_file_path: "
+      SELECT b.file_id
+
+        FROM themes a
+        JOIN theme_files b
+          ON (b.theme_id = a.theme_id)
+
+       WHERE a.theme_slug = ?
+         AND b.file_path = ?
+    ",
   }
 
   def initialize(context : Context)
@@ -230,7 +243,7 @@ class Guff::Models::ThemeModel < Guff::Models::Model
 
     db.transaction do
       # generate slug
-      slug = SecureRandom.hex(24)
+      slug = SecureRandom.hex(16)
 
       # add theme
       db.query(SQL[:add_theme], REQUIRED_FIELDS.map { |key|
@@ -271,4 +284,56 @@ class Guff::Models::ThemeModel < Guff::Models::Model
       done_cb.call(theme_id.to_i64)
     end
   end
+
+  ################
+  # file methods #
+  ################
+
+  def get_file_path(slug : String, path : String) : String?
+    # get theme
+    theme = get(slug: slug)
+    return nil unless theme
+
+    if theme["is_system"].to_s == "1"
+      File.join(
+        @context.config.system_dir,
+        "themes",
+        theme["theme_slug"].to_s,
+        "files",
+        File.expand_path(path, "/")
+      )
+    else
+      # map slug and path to file_id
+      file_id = @context.dbs.ro.one(SQL[:get_file_path], [slug, path])
+      return nil unless file_id
+
+      # build path to cached file
+      dst_path = File.join(
+        @context.config.data_dir,
+        "cache",
+        "theme-files",
+        file_id.not_nil!.to_s
+      )
+
+      unless File.exists?(dst_path)
+        # cached theme file does not exist, so extract it from
+        # theme archive and save it in cache directory
+        Zip::Archive.open(File.join(
+          @context.config.data_dir,
+          "themes",
+          theme["theme_id"].to_s
+        )) do |zip|
+          # extract file to cache
+          File.open(dst_path, "wb") do |fh|
+            zip.read(File.join("files", path)) do |buf, len|
+              fh.write(buf[0, len])
+            end
+          end
+        end
+      end
+
+      # return path
+      File.exists?(dst_path) ? dst_path : nil
+    end
+  end
 end