1 files changed, 90 insertions, 0 deletions
diff --git a/src/buildtool/build_engine/base_maps/expression_map.cpp b/src/buildtool/build_engine/base_maps/expression_map.cpp
new file mode 100644
index 00000000..df464b15
--- /dev/null
+++ b/src/buildtool/build_engine/base_maps/expression_map.cpp
@@ -0,0 +1,90 @@
+
+#include "src/buildtool/build_engine/base_maps/expression_map.hpp"
+
+#include <optional>
+#include <string>
+
+#include "fmt/core.h"
+#include "src/buildtool/build_engine/base_maps/field_reader.hpp"
+
+namespace BuildMaps::Base {
+
+auto CreateExpressionMap(gsl::not_null<ExpressionFileMap*> const& expr_file_map,
+                         std::size_t jobs) -> ExpressionFunctionMap {
+    auto expr_func_creator = [expr_file_map](auto ts,
+                                             auto setter,
+                                             auto logger,
+                                             auto subcaller,
+                                             auto const& id) {
+        if (not id.IsDefinitionName()) {
+            (*logger)(
+                fmt::format("{} cannot name an expression", id.ToString()),
+                true);
+            return;
+        }
+        expr_file_map->ConsumeAfterKeysReady(
+            ts,
+            {id.ToModule()},
+            [setter = std::move(setter),
+             logger,
+             subcaller = std::move(subcaller),
+             id](auto json_values) {
+                auto func_it = json_values[0]->find(id.name);
+                if (func_it == json_values[0]->end()) {
+                    (*logger)(fmt::format("Cannot find expression {} in {}",
+                                          id.name,
+                                          id.module),
+                              true);
+                    return;
+                }
+
+                auto reader = FieldReader::Create(
+                    func_it.value(), id, "expression", logger);
+                if (not reader) {
+                    return;
+                }
+
+                auto expr = reader->ReadExpression("expression");
+                if (not expr) {
+                    return;
+                }
+
+                auto vars = reader->ReadStringList("vars");
+                if (not vars) {
+                    return;
+                }
+
+                auto import_aliases =
+                    reader->ReadEntityAliasesObject("imports");
+                if (not import_aliases) {
+                    return;
+                }
+                auto [names, ids] = std::move(*import_aliases).Obtain();
+
+                (*subcaller)(
+                    std::move(ids),
+                    [setter = std::move(setter),
+                     vars = std::move(*vars),
+                     names = std::move(names),
+                     expr = std::move(expr)](auto const& expr_funcs) {
+                        auto imports = ExpressionFunction::imports_t{};
+                        imports.reserve(expr_funcs.size());
+                        for (std::size_t i{}; i < expr_funcs.size(); ++i) {
+                            imports.emplace(names[i], *expr_funcs[i]);
+                        }
+                        (*setter)(std::make_shared<ExpressionFunction>(
+                            vars, imports, expr));
+                    },
+                    std::move(logger));
+            },
+            [logger, id](auto msg, auto fatal) {
+                (*logger)(fmt::format("While reading expression file in {}: {}",
+                                      id.module,
+                                      msg),
+                          fatal);
+            });
+    };
+    return ExpressionFunctionMap{expr_func_creator, jobs};
+}
+
+}  // namespace BuildMaps::Base