parser base working

parser.c

@@ -0,0 +1,117 @@
+#include <assert.h>
+#include <stddef.h>
+#include <stdio.h>
+#define NB_IMPLEMENTATION
+#include "lexer.h"
+#include "nb.h"
+
+typedef struct {
+  Token *left;
+  Token *right;
+  size_t prec;
+  symbols op;
+} ASTNode;
+
+typedef struct {
+  ASTNode *nodes;
+  size_t size;
+} ASTTree;
+
+Token *copy_single_token(const Token *src, size_t i) {
+    Token *t = calloc(1, sizeof(Token));
+    assert(t);
+
+    t->size = 1;
+    t->type = malloc(sizeof(int));
+    t->text = malloc(sizeof(char*));
+    assert(t->type && t->text);
+
+    t->type[0] = src->type[i];
+    t->text[0] = strdup(src->text[i]);  
+
+    return t;
+}
+
+ssize_t find_prev_token(const Token *tok, size_t start) {
+    for (ssize_t i = (ssize_t)start; i >= 0; --i) {
+        if (tok->type[i] != TOKEN_SPACE &&
+            tok->type[i] != TOKEN_NEWLINE &&
+            tok->type[i] != TOKEN_EOF) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+ssize_t find_next_token(const Token *tok, size_t start) {
+    for (size_t i = start; i < tok->size; ++i) {
+        if (tok->type[i] != TOKEN_SPACE &&
+            tok->type[i] != TOKEN_NEWLINE &&
+            tok->type[i] != TOKEN_EOF) {
+            return i;
+        }
+    }
+    return -1;
+}
+
+
+size_t token_precedence(Token token, size_t idx){
+  switch (token.type[idx]) {
+    case TOKEN_PLUS:
+      return 1;
+      break;
+    case TOKEN_MINUS:
+      return 1;
+      break;
+    case TOKEN_MUL:
+      return 2;
+      break;
+    case TOKEN_DIV:
+      return 3;
+      break;
+    
+    default:
+      return 0;
+      break;
+  }
+}
+
+ASTTree ast_walk(Token token) {
+    ASTTree ops = {0};
+
+    ops.nodes = calloc(token.size, sizeof(ASTNode));
+    assert(ops.nodes);
+
+    for (size_t i = 0; i < token.size; ++i) {
+        switch (token_precedence(token, i) > 0) {
+          case true: {
+              ssize_t l = find_prev_token(&token, i - 1);
+              ssize_t r = find_next_token(&token, i + 1);
+              assert(l >= 0 && r >= 0);
+
+              ASTNode op = {0};
+              op.left = copy_single_token(&token, l);
+              op.right = copy_single_token(&token, r);
+              op.prec = token_precedence(token, i);
+              op.op = token.type[i];
+              ops.nodes[ops.size++] = op;
+              break;
+          }
+      }
+    }
+
+    return ops;
+}
+
+int main(int argc, char **argv){
+  Token to_tokenize = {0};
+  if (argc > 1) {
+    to_tokenize = tokenize_all(nb_read_file(argv[1]));
+  }
+  for (size_t i=0; i<to_tokenize.size; ++i){
+    printf("Type: %s\nText: %s\n\n", token_type_to_string(to_tokenize.type[i]), to_tokenize.text[i]);
+  }
+  ASTTree walked = ast_walk(to_tokenize);
+  printf("op: %s, left: %s, right: %s, prec %zu\n", token_type_to_string(walked.nodes->op), walked.nodes->left->text[0], walked.nodes->right->text[0], walked.nodes->prec);
+  return 0;
+}