stedolan-jq/c/jv.h

#ifndef JV_H
#define JV_H

#include <stdint.h>
#include <assert.h>
#include <stddef.h>



typedef enum {
  JV_KIND_INVALID,
  JV_KIND_NULL,
  JV_KIND_FALSE,
  JV_KIND_TRUE,
  JV_KIND_NUMBER,
  JV_KIND_STRING,
  JV_KIND_OBJECT,
  JV_KIND_ARRAY
} jv_kind;

typedef struct {
  size_t count;
} jv_refcnt;

typedef struct{
  jv_refcnt* ptr;
  int i[2];
} jv_complex;

typedef struct {
  jv_kind kind;
  union {
    double number;
    jv_complex complex;
  } val;
} jv;

/*
 * All jv_* functions consume (decref) input and produce (incref) output
 * Except jv_copy
 */

jv_kind jv_get_kind(jv);
static int jv_is_valid(jv x) { return jv_get_kind(x) != JV_KIND_INVALID; }

jv jv_copy(jv);
void jv_free(jv);

int jv_equal(jv, jv);

jv jv_invalid();
jv jv_null();
jv jv_true();
jv jv_false();

jv jv_number(double);
double jv_number_value(jv);

jv jv_array();
jv jv_array_sized(int);
int jv_array_length(jv);
jv jv_array_get(jv, int);
jv jv_array_set(jv, int, jv);
jv jv_array_append(jv, jv);
jv jv_array_concat(jv, jv);
jv jv_array_slice(jv, int, int);


jv jv_string(const char*);
jv jv_string_sized(const char*, int);
int jv_string_length(jv);
uint32_t jv_string_hash(jv);
const char* jv_string_value(jv);

jv jv_object();
jv jv_object_get(jv object, jv key);
jv jv_object_set(jv object, jv key, jv value);
jv jv_object_delete(jv object, jv key);
int jv_object_length(jv object);

int jv_object_iter(jv);
int jv_object_iter_next(jv, int);
int jv_object_iter_valid(jv, int);
jv jv_object_iter_key(jv, int);
jv jv_object_iter_value(jv, int);


int jv_get_refcnt(jv);

void jv_dump(jv);
jv jv_parse(const char* string);
jv jv_parse_sized(const char* string, int length);




static jv jv_lookup(jv t, jv k) {
  jv v;
  if (jv_get_kind(t) == JV_KIND_OBJECT && jv_get_kind(k) == JV_KIND_STRING) {
    v = jv_object_get(t, k);
    if (!jv_is_valid(v)) {
      v = jv_null();
    }
  } else if (jv_get_kind(t) == JV_KIND_ARRAY && jv_get_kind(k) == JV_KIND_NUMBER) {
    // FIXME: don't do lookup for noninteger index
    v = jv_array_get(t, (int)jv_number_value(k));
    if (!jv_is_valid(v)) {
      v = jv_null();
    }
  } else if (jv_get_kind(t) == JV_KIND_NULL && 
             (jv_get_kind(k) == JV_KIND_STRING || jv_get_kind(k) == JV_KIND_NUMBER)) {
    jv_free(t);
    jv_free(k);
    v = jv_null();
  } else {
    assert(0&&"bad lookup");
  }
  return v;
  // FIXME: invalid indexes, JV_KIND_INVALID
  /*
  if (v) 
    return v;
  else
    return jv_null();
  */
}

static jv jv_modify(jv t, jv k, jv v) {
  if (jv_get_kind(k) == JV_KIND_STRING) {
    if (jv_get_kind(t) == JV_KIND_NULL) {
      t = jv_object();
    }
    if (jv_get_kind(t) == JV_KIND_OBJECT) {
      t = jv_object_set(t, k, v);
    } else {
      assert(0 && "bad mod - not an object");
    }
  } else if (jv_get_kind(k) == JV_KIND_NUMBER) {
    if (jv_get_kind(t) == JV_KIND_NULL) {
      t = jv_array();
    }
    if (jv_get_kind(t) == JV_KIND_ARRAY) {
      t = jv_array_set(t, (int)jv_number_value(k), v);
    } else {
      assert(0 && "bad mod - not an array");
    }
  } else {
    assert(0 && "bad mod - seriously, wtf");
  }
  return t;
}

static jv jv_insert(jv root, jv value, jv* path, int pathlen) {
  if (pathlen == 0) {
    jv_free(root);
    return value;
  }
  return jv_modify(root, jv_copy(*path), 
                   jv_insert(jv_lookup(jv_copy(root), jv_copy(*path)), value, path+1, pathlen-1));
}









#endif


/*

true/false/null:
check kind

number:
introduce/eliminate jv
to integer

array:
copy
free
slice
index
update

updateslice?


 */