const { readFileSync } = require("fs");
const { join } = require("path");
const { cwd } = require("process");

let memory;
let instance;

const TRUE = 6 << 28;
const FALSE = 7 << 28;

function is_data(v) {
  return v >> 28 === 3;
}

const importObject = {
  lib: {
    dump_python_stack() {
      console.log("python heap", "-".repeat(10));

      const python_stack_size = 64;
      const python_sp = instance.exports.python_sp.value;

      const python_heap = new Uint32Array(
        memory.buffer.slice(0, python_stack_size)
      );
      console.log("sp", python_sp);

      for (var i = 0; i < python_sp / 4; i++) {
        const v = python_heap[i];
        if (is_data(v)) {
          if (v === TRUE) {
            console.log(i, i << 2, "true", v);
          } else if (v === FALSE) {
            console.log(i, i << 2, "false", v);
          } else {
            console.log(i, i << 2, "object", v & 0xfffffff);
          }
        } else {
          console.log(i, i << 2, "byte", v);
        }
      }

      console.log("python heap", "-".repeat(10));
    },
    print(v) {
      // {
      //   const heap = new Uint8Array(memory.buffer);
      //   const b = 65558 + 4 + 4 + 4;
      //   for (var i = 0, len = 2 * 4 * 2; i < len;) {
      //     console.log("DICT", b + i, heap[b + i], heap[b + i + 1], heap[b + i + 2], heap[b + i + 3]);
      //     i += 4
      //   }
      // }

      // console.log("raw", v);
      if (is_data(v)) {
        const ptr = v & 0xfffffff;
        const heap = new Uint8Array(memory.buffer);

        let i = 0;
        let s = "";
        while (true) {
          const c = heap[ptr + i];
          if (c === 0x0) {
            break;
          }
          s += String.fromCharCode(c);
          i++;
        }

        console.log(s);
      } else if (v === TRUE) {
        console.log("True");
      } else if (v === FALSE) {
        console.log("False");
      } else {
        console.log(v);
      }
    }
  }
};

const m = new WebAssembly.Module(readFileSync(join(cwd(), "./wasm.out"), null));
instance = new WebAssembly.Instance(m, importObject);

memory = instance.exports.mem;

instance.exports.main();