Travel3: Simple image and video display site

Reads the images and videos from filesystem and builds a site in
memroy.

1 files changed, 139 insertions, 0 deletions

diff --git a/src/tag.cc b/src/tag.cc
new file mode 100644
index 0000000..a563b9d
--- /dev/null
+++ b/src/tag.cc
@@ -0,0 +1,139 @@
+#include "common.hh"
+
+#include "htmlutil.hh"
+#include "tag.hh"
+
+#include <map>
+#include <vector>
+
+namespace {
+
+class TextRenderable : public virtual Renderable {
+public:
+  explicit TextRenderable(std::string content)
+    : content_(std::move(content)) {}
+
+  void render(std::string* out) const override {
+    html::escape(content_, out);
+  }
+
+private:
+  std::string content_;
+};
+
+class ScriptRenderable : public virtual Renderable {
+public:
+  explicit ScriptRenderable(std::string content)
+    : content_(std::move(content)) {}
+
+  void render(std::string* out) const override {
+    out->append(content_);
+  }
+
+private:
+  std::string content_;
+};
+
+class TagImpl : public Tag {
+public:
+  TagImpl(std::string name, std::string content)
+    : name_(std::move(name)) {
+    add(std::move(content));
+    assert(html::escape(name_) == name_);
+  }
+
+  std::string_view name() const override {
+    return name_;
+  }
+
+  bool empty() const override {
+    return child_.empty();
+  }
+
+  bool has_attr(std::string const& name) const override {
+    return attr_.count(name);
+  }
+
+  Tag* clear_content() override {
+    child_.clear();
+    return this;
+  }
+
+  Tag* attr(std::string name, std::string value) override {
+    assert(html::escape(name) == name);
+    attr_[name] = std::move(value);
+    return this;
+  }
+
+  Tag* add(std::string content) override {
+    if (!content.empty()) {
+      if (name_ == "script") {
+        child_.push_back(
+            std::make_unique<ScriptRenderable>(std::move(content)));
+      } else {
+        child_.push_back(std::make_unique<TextRenderable>(std::move(content)));
+      }
+    }
+    return this;
+  }
+
+  Tag* add(std::unique_ptr<Tag> tag) override {
+    auto* ret = tag.get();
+    child_.push_back(std::move(tag));
+    return ret;
+  }
+
+  void render(std::string* out) const override {
+    size_t need = 1 + name_.size();
+    for (auto const& pair : attr_)
+      need += 1 + pair.first.size() + 2 + pair.second.size() + 1;
+    if (empty())
+      ++need;
+    out->reserve(need);
+    out->push_back('<');
+    out->append(name_);
+    for (auto const& pair : attr_) {
+      out->push_back(' ');
+      out->append(pair.first);
+      out->append("=\"");
+      html::escape(pair.second, out, html::EscapeTarget::ATTRIBUTE);
+      out->push_back('"');
+    }
+    if (empty()) {
+      if (name_ == "script") {
+        // Some browsers don't allow <script src=""/>, must be written as
+        // <script src=""></script>
+        out->append("></script>");
+      } else {
+        // There are tags, like <br> where the / is optional but why botter.
+        out->append("/>");
+      }
+      return;
+    }
+    out->push_back('>');
+
+    for (auto& child : child_) {
+      child->render(out);
+    }
+
+    out->reserve(name_.size() + 3);
+    out->append("</");
+    out->append(name_);
+    out->push_back('>');
+  }
+
+private:
+  std::string name_;
+  std::map<std::string, std::string> attr_;
+  std::vector<std::unique_ptr<Renderable>> child_;
+};
+
+}  // namespace
+
+Tag* Tag::add_tag(std::string name, std::string content) {
+  return add(create(std::move(name), std::move(content)));
+}
+
+std::unique_ptr<Tag> Tag::create(std::string name, std::string content) {
+  return std::make_unique<TagImpl>(std::move(name), std::move(content));
+}