Implement new magic frontend using sexpr

1 files changed, 130 insertions, 0 deletions

diff --git a/src/sexpr/main.cpp b/src/sexpr/main.cpp
new file mode 100644
index 0000000..7d63ddf
--- /dev/null
+++ b/src/sexpr/main.cpp
@@ -0,0 +1,130 @@
+#include <stack>
+#include <map>
+
+#include "../io/cxxstdio.hpp"
+
+#include "lexer.hpp"
+#include "parser.hpp"
+
+#include "../poison.hpp"
+
+enum Spacing
+{
+    LINES,
+    SIMPLE,
+    SPACES,
+    SPACES_1,
+    SPACES_2,
+    SPACES_3,
+    SPACES_4,
+};
+
+static
+void do_spacing(bool& first, Spacing& sp, int depth)
+{
+    if (first)
+    {
+        first = false;
+        return;
+    }
+    switch (sp)
+    {
+    case LINES:
+        PRINTF("\n%*s", (depth - 1) * 4, "");
+        return;
+    case SPACES:
+    case SIMPLE:
+        PRINTF(" ");
+        return;
+    case SPACES_1:
+        PRINTF(" ");
+        sp = LINES;
+        return;
+    case SPACES_2:
+        PRINTF(" ");
+        sp = SPACES_1;
+        return;
+    case SPACES_3:
+        PRINTF(" ");
+        sp = SPACES_2;
+        return;
+    case SPACES_4:
+        PRINTF(" ");
+        sp = SPACES_3;
+        return;
+    }
+}
+
+static
+void adjust_spacing(Spacing& sp, ZString val)
+{
+    std::map<ZString, Spacing> spaces =
+    {
+        {"BLOCK", LINES},
+        {"GUARD", LINES},
+        {"DISABLED", LINES},
+        {"PROCEDURE", SPACES_2},
+        {"SPELL", SPACES_4},
+        {"IF", SPACES_1},
+        {"set_script_variable", SPACES_2},
+    };
+    auto it = spaces.find(val);
+    if (it != spaces.end())
+        sp = it->second;
+}
+
+int main()
+{
+    if (1 == 1)
+    {
+        sexpr::Lexer lexer("/dev/stdin");
+        sexpr::SExpr sexpr;
+        while (sexpr::parse(lexer, sexpr))
+        {
+            PRINTF("");
+        }
+        if (lexer.peek() != sexpr::TOK_EOF)
+        {
+            lexer.span().error(STRPRINTF("Incomplete: %s: %s\n",
+                        sexpr::token_name(lexer.peek()), lexer.val_string()));
+        }
+        return 0;
+    }
+
+    std::stack<Spacing> spacing;
+    spacing.push(LINES);
+    sexpr::Lexer lexer("/dev/stdin");
+    bool first = true;
+    while (sexpr::Lexeme tok = lexer.peek())
+    {
+        switch (tok)
+        {
+        case sexpr::TOK_OPEN:
+            if (spacing.top() == SIMPLE)
+                spacing.top() = LINES;
+            do_spacing(first, spacing.top(), spacing.size());
+            PRINTF("(");
+            spacing.push(SIMPLE);
+            first = true;
+            break;
+        case sexpr::TOK_CLOSE:
+            PRINTF(")");
+            spacing.pop();
+            first = false;
+            break;
+        case sexpr::TOK_STRING:
+            do_spacing(first, spacing.top(), spacing.size());
+            PRINTF("%s", sexpr::escape(lexer.val_string()));
+            break;
+        case sexpr::TOK_TOKEN:
+            do_spacing(first, spacing.top(), spacing.size());
+            PRINTF("%s", lexer.val_string());
+            adjust_spacing(spacing.top(), lexer.val_string());
+            break;
+        default:
+            abort();
+        }
+        lexer.adv();
+    }
+    PRINTF("\n");
+}