extract ParametersParser to it's own file

1 files changed, 103 insertions, 0 deletions

diff --git a/src/parameters_parser.cc b/src/parameters_parser.cc
new file mode 100644
index 00000000..cdcfb0c1
--- /dev/null
+++ b/src/parameters_parser.cc
@@ -0,0 +1,103 @@
+#include "parameters_parser.hh"
+
+namespace Kakoune
+{
+
+ParametersParser::ParametersParser(const ParameterList& params,
+                                   std::unordered_map<String, bool> options)
+    : m_params(params), m_positional(params.size(), true),
+      m_options(std::move(options))
+{
+    for (size_t i = 0; i < params.size(); ++i)
+    {
+        if (params[i][0] == '-')
+        {
+            auto it = m_options.find(params[i].substr(1_byte));
+            if (it == m_options.end())
+                throw unknown_option(params[i]);
+
+            if (it->second)
+            {
+                if (i + 1 == params.size() or params[i+1][0] == '-')
+                   throw missing_option_value(params[i]);
+
+                m_positional[i+1] = false;
+            }
+            m_positional[i] = false;
+        }
+
+        // all options following -- are positional
+        if (params[i] == "--")
+            break;
+    }
+}
+
+bool ParametersParser::has_option(const String& name) const
+{
+    assert(m_options.find(name) != m_options.end());
+    for (auto& param : m_params)
+    {
+        if (param[0] == '-' and param.substr(1_byte) == name)
+            return true;
+
+        if (param == "--")
+            break;
+    }
+    return false;
+}
+
+const String& ParametersParser::option_value(const String& name) const
+{
+    auto it = m_options.find(name);
+    assert(it != m_options.end());
+    assert(it->second == true);
+
+    for (size_t i = 0; i < m_params.size(); ++i)
+    {
+        if (m_params[i][0] == '-' and m_params[i].substr(1_byte) == name)
+            return m_params[i+1];
+
+        if (m_params[i] == "--")
+            break;
+    }
+    static String empty;
+    return empty;
+}
+
+size_t ParametersParser::positional_count() const
+{
+    size_t res = 0;
+    for (bool positional : m_positional)
+    {
+       if (positional)
+           ++res;
+    }
+    return res;
+}
+
+const String& ParametersParser::operator[] (size_t index) const
+{
+    assert(index < positional_count());
+    iterator it = begin();
+    while (index)
+    {
+        ++it;
+        --index;
+    }
+    return *it;
+}
+
+ParametersParser::iterator ParametersParser::begin() const
+{
+    int index = 0;
+    while (index < m_positional.size() and not m_positional[index])
+        ++index;
+    return iterator(*this, index);
+}
+
+ParametersParser::iterator ParametersParser::end() const
+{
+    return iterator(*this, m_params.size());
+}
+
+}