#ifndef PDF_H
#define PDF_H

#include <stdarg.h>
#include <stddef.h>
#include "studio/geometry.h"

#define PAGES 32

struct pdf {
    size_t (*write)(void *, const char *, va_list);
    void *device;
    const char *title;
    const char *author;
    size_t offset;
    struct {
        size_t parent;
        size_t number;
        size_t object[PAGES];
    } page;
    struct {
        size_t number;
        size_t offset[PAGES * 4];
    } object;
} generate(struct pdf, const char *, ...);

#undef PAGES

static inline struct pdf point(const struct pdf pdf, const vector point)
{
    return generate(pdf, "%.2f %.2f ", point.x, point.y);
}

static inline struct pdf ctm(const struct pdf pdf, const matrix CTM)
{
    return generate(pdf, "%0.2f %0.2f %0.2f %0.2f %0.2f %0.2f cm\n", CTM.a, CTM.b, CTM.c, CTM.d, CTM.tx, CTM.ty);
}

struct pdf dictionary(struct pdf, const char *, ...);
struct pdf endpage(struct pdf, struct pdf);
struct pdf endpdf(struct pdf);
struct pdf offset(struct pdf, size_t);
struct pdf startpage(struct pdf, vector, size_t);
struct pdf startpdf(struct pdf);

#define mm * (72.0 / 25.4)

extern const vector a0;
extern const vector a1;
extern const vector a2;
extern const vector a3;
extern const vector a4;
extern const vector a5;
extern const vector a6;
extern const vector a7;
extern const vector a8;
extern const vector usletter;

static inline vector portrait(const vector page)
{
    return (page.x <= page.y) ? page : (vector){.x = page.y, .y = page.x};
}

static inline vector landscape(const vector page)
{
    return (page.x >= page.y) ? page : (vector){.x = page.y, .y = page.x};
}

#endif