#pragma once

// ------------------------------------------------------------------------
// Standard library

#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include <math.h>
#include <ctype.h>
#include <stdio.h>

#include <unistd.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <sys/types.h>

// ----------------------------------------------------------------------------
// Dynamic array. 

typedef struct bufHdr
{
    vlong len;
    vlong cap;
    byte  buf[];
} bufHdr;

#define _bufHdr(s) ((bufHdr*)((uint8*)(s)-offsetof(bufHdr, buf)))
#define buflen(s) ((s) ? (_bufHdr(s)->len) : 0)
#define bufcap(s) ((s) ? (_bufHdr(s)->cap) : 0)
#define bufend(s) ((s) + buflen(s))
#define bufsize(s) ((s) ? (buflen(s) * sizeof((s)[0])) : 0)

#define buffree(s) ((s) ? (free(_bufHdr(s)), (s) = nil) : 0)
#define buffit(s, n) ((n) <= bufcap(s) ? 0 : ((s) = bufgrow((s), (n), sizeof(*(s)))))

#define bufresize(s, n)                                                        \
    do {                                                                       \
        (buffit(s, n));                                                        \
        ((_bufHdr(s)->len) = (n));                                             \
    } while (0)

#define bufpush(s, ...) (buffit((s), 1 + buflen(s)), (s)[_bufHdr(s)->len++] = (__VA_ARGS__))

#define bufpop(s, i) (_bufpop((s), (i), sizeof(*(s))), (s)[_bufHdr(s)->len])

void* bufgrow(void*, vlong, vlong);
void _bufpop(void*, int, vlong);

// -----------------------------------------------------------------------------
// Memory allocation

typedef struct mem·Allocator {
    void *(*alloc)(ulong size);
    void *(*realloc)(void *ptr, ulong size);
    void (*free)(void *ptr);
} mem·Allocator;

static mem·Allocator mem·sys = { .alloc = &malloc, .realloc = &realloc, .free = &free };

typedef struct mem·Arena mem·Arena;

mem·Arena *mem·newarena(mem·Allocator from);
void      *mem·arenaalloc(mem·Arena *A, ulong size); 
void       mem·freearena(mem·Arena *A);

// -----------------------------------------------------------------------------
// Co-routines

typedef struct Coro Coro;

Coro*   coro·new(uintptr stk, uintptr (*func)(Coro*, uintptr));
uintptr coro·yield(Coro *c, uintptr arg);
error   coro·free(Coro *c);

// -----------------------------------------------------------------------------
// Strings

// TODO(nnoll): Move here?
#include ".include/str.h"

// -----------------------------------------------------------------------------
// Maps or dictionaries

#include ".include/map.h"

// -----------------------------------------------------------------------------
// I/O

typedef FILE Stream;
enum SeekPos
{
    seek·CUR = SEEK_CUR,
    seek·SET = SEEK_SET,
    seek·END = SEEK_END
};

Stream *io·open(byte *name, byte *mode);
error   io·close(Stream *s);
byte    io·getbyte(Stream *s);
error   io·ungetbyte(Stream *s, byte c);
vlong   io·read(Stream *s, int sz, int n, void *buf);
int     io·readln(Stream *s, int n, byte* buf);
error   io·putbyte(Stream *s, byte c);
int     io·putstring(Stream *s, string str);
vlong   io·write(Stream *s, int sz, int n, void *buf);
int     io·flush(Stream *s);
int     io·seek(Stream *s, long off, enum SeekPos origin);

// -----------------------------------------------------------------------------
// Buffered I/O

// -----------------------------------------------------------------------------
// Error handling functions.

void errorf(const byte* fmt, ...);

#define panicf(...)  (errorf(__VA_ARGS__), assert(0))