#include "jsi.h"

static void jsB_Function(js_State *J)

{

  int i, top = js_gettop(J);

  js_Buffer *sb = NULL;

  const char *body;

  js_Ast *parse;

  js_Function *fun;

  if (js_try(J)) {

    js_free(J, sb);

    jsP_freeparse(J);

    js_throw(J);

  }

  /* p1, p2, ..., pn */

  if (top > 2) {

    for (i = 1; i < top - 1; ++i) {

      if (i > 1)

        js_putc(J, &sb, ',');

      js_puts(J, &sb, js_tostring(J, i));

    }

    js_putc(J, &sb, ')');

    js_putc(J, &sb, 0);

  }

  /* body */

  body = js_isdefined(J, top - 1) ? js_tostring(J, top - 1) : "";

  parse = jsP_parsefunction(J, "[string]", sb ? sb->s : NULL, body);

  fun = jsC_compilefunction(J, parse);

  js_endtry(J);

  js_free(J, sb);

  jsP_freeparse(J);

  js_newfunction(J, fun, J->GE);

}

static void jsB_Function_prototype(js_State *J)

{

  js_pushundefined(J);

}

static void Fp_toString(js_State *J)

{

  js_Object *self = js_toobject(J, 0);

  js_Buffer *sb = NULL;

  int i;

  if (!js_iscallable(J, 0))

    js_typeerror(J, "not a function");

  if (self->type == JS_CFUNCTION || self->type == JS_CSCRIPT) {

    js_Function *F = self->u.f.function;

    if (js_try(J)) {

      js_free(J, sb);

      js_throw(J);

    }

    js_puts(J, &sb, "function ");

    js_puts(J, &sb, F->name);

    js_putc(J, &sb, '(');

    for (i = 0; i < F->numparams; ++i) {

      if (i > 0) js_putc(J, &sb, ',');

      js_puts(J, &sb, F->vartab[i]);

    }

    js_puts(J, &sb, ") { [byte code] }");

    js_putc(J, &sb, 0);

    js_pushstring(J, sb->s);

    js_endtry(J);

    js_free(J, sb);

  } else if (self->type == JS_CCFUNCTION) {

    if (js_try(J)) {

      js_free(J, sb);

      js_throw(J);

    }

    js_puts(J, &sb, "function ");

    js_puts(J, &sb, self->u.c.name);

    js_puts(J, &sb, "() { [native code] }");

    js_putc(J, &sb, 0);

    js_pushstring(J, sb->s);

    js_endtry(J);

    js_free(J, sb);

  } else {

    js_pushliteral(J, "function () { }");

  }

}

static void Fp_apply(js_State *J)

{

  int i, n;

  if (!js_iscallable(J, 0))

    js_typeerror(J, "not a function");

  js_copy(J, 0);

  js_copy(J, 1);

  if (js_isnull(J, 2) || js_isundefined(J, 2)) {

    n = 0;

  } else {

    n = js_getlength(J, 2);

    if (n < 0)

      n = 0;

    for (i = 0; i < n; ++i)

      js_getindex(J, 2, i);

  }

  js_call(J, n);

}

static void Fp_call(js_State *J)

{

  int i, top = js_gettop(J);

  if (!js_iscallable(J, 0))

    js_typeerror(J, "not a function");

  for (i = 0; i < top; ++i)

    js_copy(J, i);

  js_call(J, top - 2);

}

static void callbound(js_State *J)

{

  int top = js_gettop(J);

  int i, fun, args, n;

  fun = js_gettop(J);

  js_currentfunction(J);

  js_getproperty(J, fun, "__TargetFunction__");

  js_getproperty(J, fun, "__BoundThis__");

  args = js_gettop(J);

  js_getproperty(J, fun, "__BoundArguments__");

  n = js_getlength(J, args);

  if (n < 0)

    n = 0;

  for (i = 0; i < n; ++i)

    js_getindex(J, args, i);

  js_remove(J, args);

  for (i = 1; i < top; ++i)

    js_copy(J, i);

  js_call(J, n + top - 1);

}

static void constructbound(js_State *J)

{

  int top = js_gettop(J);

  int i, fun, args, n;

  fun = js_gettop(J);

  js_currentfunction(J);

  js_getproperty(J, fun, "__TargetFunction__");

  args = js_gettop(J);

  js_getproperty(J, fun, "__BoundArguments__");

  n = js_getlength(J, args);

  if (n < 0)

    n = 0;

  for (i = 0; i < n; ++i)

    js_getindex(J, args, i);

  js_remove(J, args);

  for (i = 1; i < top; ++i)

    js_copy(J, i);

  js_construct(J, n + top - 1);

}

static void Fp_bind(js_State *J)

{

  int i, top = js_gettop(J);

  int n;

  if (!js_iscallable(J, 0))

    js_typeerror(J, "not a function");

  n = js_getlength(J, 0);

  if (n > top - 2)

    n -= top - 2;

  else

    n = 0;

  /* Reuse target function's prototype for HasInstance check. */

  js_getproperty(J, 0, "prototype");

  js_newcconstructor(J, callbound, constructbound, "[bind]", n);

  /* target function */

  js_copy(J, 0);

  js_defproperty(J, -2, "__TargetFunction__", JS_READONLY | JS_DONTENUM | JS_DONTCONF);

  /* bound this */

  js_copy(J, 1);

  js_defproperty(J, -2, "__BoundThis__", JS_READONLY | JS_DONTENUM | JS_DONTCONF);

  /* bound arguments */

  js_newarray(J);

  for (i = 2; i < top; ++i) {

    js_copy(J, i);

    js_setindex(J, -2, i - 2);

  }

  js_defproperty(J, -2, "__BoundArguments__", JS_READONLY | JS_DONTENUM | JS_DONTCONF);

}

void jsB_initfunction(js_State *J)

{

  J->Function_prototype->u.c.name = "Function.prototype";

  J->Function_prototype->u.c.function = jsB_Function_prototype;

  J->Function_prototype->u.c.constructor = NULL;

  J->Function_prototype->u.c.length = 0;

  js_pushobject(J, J->Function_prototype);

  {

    jsB_propf(J, "Function.prototype.toString", Fp_toString, 2);

    jsB_propf(J, "Function.prototype.apply", Fp_apply, 2);

    jsB_propf(J, "Function.prototype.call", Fp_call, 1);

    jsB_propf(J, "Function.prototype.bind", Fp_bind, 1);

  }

  js_newcconstructor(J, jsB_Function, jsB_Function, "Function", 1);

  js_defglobal(J, "Function", JS_DONTENUM);

}