/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 *
 * The Original Code is Copyright (C) 2009 Blender Foundation.
 * All rights reserved.
 */

/** \file
 * \ingroup blf
 */

#ifndef __BLF_API_H__
#define __BLF_API_H__

#include "BLI_compiler_attrs.h"
#include "BLI_sys_types.h"

#ifdef __cplusplus
extern "C" {
#endif

/* enable this only if needed (unused circa 2016) */
#define BLF_BLUR_ENABLE 0

struct ColorManagedDisplay;
struct ResultBLF;
struct rctf;
struct rcti;

int BLF_init(void);
void BLF_exit(void);
void BLF_default_dpi(int dpi);
void BLF_default_set(int fontid);
int BLF_default(void);      /* get default font ID so we can pass it to other functions */
void BLF_batch_reset(void); /* call when changing opengl context. */

void BLF_cache_clear(void);

/* Loads a font, or returns an already loaded font and increments its reference count. */
int BLF_load(const char *name) ATTR_NONNULL();
int BLF_load_mem(const char *name, const unsigned char *mem, int mem_size) ATTR_NONNULL();

int BLF_load_unique(const char *name) ATTR_NONNULL();
int BLF_load_mem_unique(const char *name, const unsigned char *mem, int mem_size) ATTR_NONNULL();

void BLF_unload(const char *name) ATTR_NONNULL();
void BLF_unload_id(int fontid);

/* Check if font supports a particular glyph. */
bool BLF_has_glyph(int fontid, unsigned int unicode);

/* Attach a file with metrics information from memory. */
void BLF_metrics_attach(int fontid, unsigned char *mem, int mem_size);

void BLF_aspect(int fontid, float x, float y, float z);
void BLF_position(int fontid, float x, float y, float z);
void BLF_size(int fontid, int size, int dpi);

/* goal: small but useful color API */
void BLF_color4ubv(int fontid, const unsigned char rgba[4]);
void BLF_color3ubv(int fontid, const unsigned char rgb[3]);
void BLF_color3ubv_alpha(int fontid, const unsigned char rgb[3], unsigned char alpha);
void BLF_color4ub(
    int fontid, unsigned char r, unsigned char g, unsigned char b, unsigned char alpha);
void BLF_color3ub(int fontid, unsigned char r, unsigned char g, unsigned char b);
void BLF_color4f(int fontid, float r, float g, float b, float a);
void BLF_color4fv(int fontid, const float rgba[4]);
void BLF_color3f(int fontid, float r, float g, float b);
void BLF_color3fv_alpha(int fontid, const float rgb[3], float alpha);
/* also available: UI_FontThemeColor(fontid, colorid) */

/* Set a 4x4 matrix to be multiplied before draw the text.
 * Remember that you need call BLF_enable(BLF_MATRIX)
 * to enable this.
 *
 * The order of the matrix is like GL:
 *
 *  | m[0]  m[4]  m[8]  m[12] |
 *  | m[1]  m[5]  m[9]  m[13] |
 *  | m[2]  m[6]  m[10] m[14] |
 *  | m[3]  m[7]  m[11] m[15] |
 */
void BLF_matrix(int fontid, const float m[16]);

/* Batch drawcalls together as long as
 * the modelview matrix and the font remain unchanged. */
void BLF_batch_draw_begin(void);
void BLF_batch_draw_flush(void);
void BLF_batch_draw_end(void);

/* Draw the string using the default font, size and dpi. */
void BLF_draw_default(float x, float y, float z, const char *str, size_t len) ATTR_NONNULL();
void BLF_draw_default_ascii(float x, float y, float z, const char *str, size_t len) ATTR_NONNULL();

/* Set size and DPI, and return default font ID. */
int BLF_set_default(void);

/* Draw the string using the current font. */
void BLF_draw_ex(int fontid, const char *str, size_t len, struct ResultBLF *r_info)
    ATTR_NONNULL(2);
void BLF_draw(int fontid, const char *str, size_t len) ATTR_NONNULL(2);
void BLF_draw_ascii_ex(int fontid, const char *str, size_t len, struct ResultBLF *r_info)
    ATTR_NONNULL(2);
void BLF_draw_ascii(int fontid, const char *str, size_t len) ATTR_NONNULL(2);
int BLF_draw_mono(int fontid, const char *str, size_t len, int cwidth) ATTR_NONNULL(2);

typedef bool (*BLF_GlyphBoundsFn)(const char *str,
                                  const size_t str_ofs,
                                  const struct rcti *glyph_bounds,
                                  const int glyph_advance_x,
                                  void *user_data);

void BLF_boundbox_foreach_glyph_ex(int fontid,
                                   const char *str,
                                   size_t len,
                                   BLF_GlyphBoundsFn user_fn,
                                   void *user_data,
                                   struct ResultBLF *r_info) ATTR_NONNULL(2);
void BLF_boundbox_foreach_glyph(int fontid,
                                const char *str,
                                size_t len,
                                BLF_GlyphBoundsFn user_fn,
                                void *user_data) ATTR_NONNULL(2);

/* Get the string byte offset that fits within a given width */
size_t BLF_width_to_strlen(int fontid, const char *str, size_t len, float width, float *r_width)
    ATTR_NONNULL(2);
/* Same as BLF_width_to_strlen but search from the string end */
size_t BLF_width_to_rstrlen(int fontid, const char *str, size_t len, float width, float *r_width)
    ATTR_NONNULL(2);

/* This function return the bounding box of the string
 * and are not multiplied by the aspect.
 */
void BLF_boundbox_ex(int fontid,
                     const char *str,
                     size_t len,
                     struct rctf *box,
                     struct ResultBLF *r_info) ATTR_NONNULL(2);
void BLF_boundbox(int fontid, const char *str, size_t len, struct rctf *box) ATTR_NONNULL();

/* The next both function return the width and height
 * of the string, using the current font and both value
 * are multiplied by the aspect of the font.
 */
float BLF_width_ex(int fontid, const char *str, size_t len, struct ResultBLF *r_info)
    ATTR_WARN_UNUSED_RESULT ATTR_NONNULL(2);
float BLF_width(int fontid, const char *str, size_t len) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();
float BLF_height_ex(int fontid, const char *str, size_t len, struct ResultBLF *r_info)
    ATTR_WARN_UNUSED_RESULT ATTR_NONNULL(2);
float BLF_height(int fontid, const char *str, size_t len) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();

/* Return dimensions of the font without any sample text. */
int BLF_height_max(int fontid) ATTR_WARN_UNUSED_RESULT;
float BLF_width_max(int fontid) ATTR_WARN_UNUSED_RESULT;
float BLF_descender(int fontid) ATTR_WARN_UNUSED_RESULT;
float BLF_ascender(int fontid) ATTR_WARN_UNUSED_RESULT;

/* The following function return the width and height of the string, but
 * just in one call, so avoid extra freetype2 stuff.
 */
void BLF_width_and_height(int fontid, const char *str, size_t len, float *r_width, float *r_height)
    ATTR_NONNULL();

/* For fixed width fonts only, returns the width of a
 * character.
 */
float BLF_fixed_width(int fontid) ATTR_WARN_UNUSED_RESULT;

/* By default, rotation and clipping are disable and
 * have to be enable/disable using BLF_enable/disable.
 */
void BLF_rotation(int fontid, float angle);
void BLF_clipping(int fontid, float xmin, float ymin, float xmax, float ymax);
void BLF_wordwrap(int fontid, int wrap_width);

#if BLF_BLUR_ENABLE
void BLF_blur(int fontid, int size);
#endif

void BLF_enable(int fontid, int option);
void BLF_disable(int fontid, int option);

/* Shadow options, level is the blur level, can be 3, 5 or 0 and
 * the other argument are the rgba color.
 * Take care that shadow need to be enable using BLF_enable!!!
 */
void BLF_shadow(int fontid, int level, const float rgba[4]) ATTR_NONNULL(3);

/* Set the offset for shadow text, this is the current cursor
 * position plus this offset, don't need call BLF_position before
 * this function, the current position is calculate only on
 * BLF_draw, so it's safe call this whenever you like.
 */
void BLF_shadow_offset(int fontid, int x, int y);

/* Set the buffer, size and number of channels to draw, one thing to take care is call
 * this function with NULL pointer when we finish, for example:
 *
 *     BLF_buffer(my_fbuf, my_cbuf, 100, 100, 4, true, NULL);
 *
 *     ... set color, position and draw ...
 *
 *     BLF_buffer(NULL, NULL, NULL, 0, 0, false, NULL);
 */
void BLF_buffer(int fontid,
                float *fbuf,
                unsigned char *cbuf,
                int w,
                int h,
                int nch,
                struct ColorManagedDisplay *display);

/* Set the color to be used for text. */
void BLF_buffer_col(int fontid, const float rgba[4]) ATTR_NONNULL(2);

/* Draw the string into the buffer, this function draw in both buffer,
 * float and unsigned char _BUT_ it's not necessary set both buffer, NULL is valid here.
 */
void BLF_draw_buffer_ex(int fontid, const char *str, size_t len, struct ResultBLF *r_info)
    ATTR_NONNULL(2);
void BLF_draw_buffer(int fontid, const char *str, size_t len) ATTR_NONNULL(2);

/* Add a path to the font dir paths. */
void BLF_dir_add(const char *path) ATTR_NONNULL();

/* Remove a path from the font dir paths. */
void BLF_dir_rem(const char *path) ATTR_NONNULL();

/* Return an array with all the font dir (this can be used for filesel) */
char **BLF_dir_get(int *ndir) ATTR_WARN_UNUSED_RESULT ATTR_NONNULL();

/* Free the data return by BLF_dir_get. */
void BLF_dir_free(char **dirs, int count) ATTR_NONNULL();

/* blf_thumbs.c */
void BLF_thumb_preview(const char *filename,
                       const char **draw_str,
                       const char **i18n_draw_str,
                       const unsigned char draw_str_lines,
                       const float font_color[4],
                       const int font_size,
                       unsigned char *buf,
                       int w,
                       int h,
                       int channels) ATTR_NONNULL();

/* blf_font_default.c */
int BLF_load_default(const bool unique);
int BLF_load_mono_default(const bool unique);

#ifdef DEBUG
void BLF_state_print(int fontid);
#endif

/* font->flags. */
#define BLF_ROTATION (1 << 0)
#define BLF_CLIPPING (1 << 1)
#define BLF_SHADOW (1 << 2)
#define BLF_KERNING_DEFAULT (1 << 3)
#define BLF_MATRIX (1 << 4)
#define BLF_ASPECT (1 << 5)
#define BLF_WORD_WRAP (1 << 6)
#define BLF_MONOCHROME (1 << 7) /* no-AA */
#define BLF_HINTING_NONE (1 << 8)
#define BLF_HINTING_SLIGHT (1 << 9)
#define BLF_HINTING_FULL (1 << 10)

#define BLF_DRAW_STR_DUMMY_MAX 1024

/* XXX, bad design */
extern int blf_mono_font;
extern int blf_mono_font_render; /* don't mess drawing with render threads. */

/**
 * Result of drawing/evaluating the string
 */
struct ResultBLF {
  /**
   * Number of lines drawn when #BLF_WORD_WRAP is enabled (both wrapped and `\n` newline).
   */
  int lines;
  /**
   * The 'cursor' position on completion (ignoring character boundbox).
   */
  int width;
};

#ifdef __cplusplus
}
#endif

#endif /* __BLF_API_H__ */
