LCOM1920-T5G03

#include <lcom/lcf.h>

#include "font.h"

#include "xpm_utils.h"

#include "graph.h"

#include "utils.h"

#include "errors.h"

#include <assert.h>

/**

 * @brief Text glyph. Represents a letter that can be drawn.

 */

typedef struct {

    uint16_t w, h;

    uint8_t *map;

} glyph_t;

/**

 * @brief Construct glyph.

 * @param   xpm XPM describing the glyph

 * @return      Pointer to created glyph

 */

static glyph_t* (glyph_ctor)(const char **xpm){

    if(xpm == NULL) return NULL;

    glyph_t *ret = malloc(sizeof(glyph_t));

    if(ret == NULL) return NULL;

    enum xpm_image_type type = XPM_8_8_8_8;

    xpm_image_t img;

    ret->map = NULL;

    uint8_t *map = xpm_load((xpm_map_t)xpm, type, &img);

    if(map == NULL){

        free(ret);

        return NULL;

    }

    ret->w = img.width;

    ret->h = img.height;

    ret->map = malloc(ret->w*ret->h*sizeof(uint8_t));

    if(ret->map == NULL){

        free(ret);

        return NULL;

    }

    for(unsigned i = 0; i < ret->w*ret->h; ++i){

        ret->map[i] = map[4*i+3];

    }

    return ret;

}

/**

 * @brief Destruct glyph.

 * @param   p   Pointer to glyph to be destroyed

 */

static void (glyph_dtor)(glyph_t *p){

    if(p == NULL) return;

    free(p->map);

    free(p);

}

/**

 * @brief Draw glyph to an alpha-buffer.

 *

 * An alpha-buffer is an array of uint8_t that represents transparencies.

 * It proves fit as a tool for drawing text.

 * @param   p       Pointer to glyph to be drawn

 * @param   x       X-position to draw the glyph

 * @param   y       Y-position to draw the glyph

 * @param   alp_buf Alpha-buffer to which the glyph will be drawn

 * @param   W       Width of the alpha-buffer

 * @param   H       Height of the alpha-buffer

 */

static int (glyph_draw_to_alpha_buffer)(const glyph_t *p, int16_t x, int16_t y, uint8_t *alp_buf, uint16_t W, uint16_t H){

    if(p == NULL) return NULL_PTR;

    for(int16_t h = 0; h < p->h; ++h){

        for(int16_t w = 0; w < p->w; ++w){

            uint8_t a = *(p->map + w + h*p->w);

            int16_t x_ = x+w, y_ = y-p->h+h;

            unsigned pos = x_ +y_*W;

            alp_buf[pos] = a;

        }

    }

    return SUCCESS;

}

/// FONT

struct font{

    size_t nchars;

    glyph_t **glyphs;

};

font_t* (font_ctor)(const char *s){

    font_t *ret = malloc(sizeof(font_t));

    if(ret == NULL) return NULL;

    ret->nchars = 128;

    ret->glyphs = malloc(ret->nchars*sizeof(glyph_t*));

    if(ret->glyphs == NULL){

        free(ret->glyphs);

        free(ret);

        return NULL;

    }

    int good = false;

    char filepath[1024];

    for(size_t i = 0; i < ret->nchars; ++i){

        sprintf(filepath, "%s/ascii%03d.xpm2", s, i);

        char **xpm = xpm_load_xpm2(filepath);

        ret->glyphs[i] = glyph_ctor((const char**)xpm);

        if(ret->glyphs[i] != NULL) good = true;

    }

    if(good) return ret;

    else{

        //font_dtor(ret);

        return NULL;

    }

}

void (font_dtor)(font_t *p){

    if(p == NULL) return;

    for(size_t i = 0; i < p->nchars; ++i)

        glyph_dtor(p->glyphs[i]);

    free(p->glyphs);

    free(p);

}

static font_t *consolas     = NULL;

static font_t *default_font = NULL;

int (font_init)(void){

    consolas = font_ctor("/home/lcom/labs/proj/media/font/Consolas/xpm2");

    if(consolas == NULL) return NULL_PTR;

    default_font = consolas;

    return SUCCESS;

}

const font_t* font_get_default(void){ return default_font; }

const font_t* font_get_consolas(void){ return consolas; }

void (font_free)(void){

    font_dtor(consolas);

    consolas = NULL;

    default_font = NULL;

}

/// TEXT

struct text{

    const font_t *fnt;

    char *txt;

    int16_t x, y;

    int size;

    uint32_t color;

    text_valign valign;

    text_halign halign;

};

text_t* (text_ctor)(const font_t *fnt, const char *txt){

    if(fnt == NULL) return NULL;

    text_t *ret = malloc(sizeof(text_t));

    if(ret == NULL) return NULL;

    ret->fnt = fnt;

    ret->txt = NULL;

    text_set_string(ret, txt);

    ret->x = 0;

    ret->y = 0;

    ret->size = 25;

    ret->color = GRAPH_BLACK;

    ret->valign = text_valign_top;

    ret->halign = text_halign_left;

    return ret;

}

void (text_dtor)(text_t *p){

    if(p == NULL) return;

    free(p->txt);

    free(p);

}

void (text_set_string) (text_t *p, const char *txt){

    size_t sz = strlen(txt);

    p->txt = realloc(p->txt, (sz+1)*sizeof(char));

    if(p->txt == NULL) return;

    strcpy(p->txt, txt);

}

const char* (text_get_string)(const text_t *p){return p->txt; }

void (text_set_pos)   (text_t *p, int16_t x, int16_t y){ p->x = x; p->y = y; }

void (text_set_size)  (text_t *p, unsigned size       ){ p->size = size    ; }

void (text_set_color) (text_t *p, uint32_t color      ){ p->color = color  ; }

void (text_set_valign)(text_t *p, text_valign valign  ){ p->valign = valign; }

void (text_set_halign)(text_t *p, text_halign halign  ){ p->halign = halign; }

int16_t (text_get_x)  (const text_t *p){ return p->x; }

int16_t (text_get_y)  (const text_t *p){ return p->y; }

int (text_draw)(const text_t *p){

    if(p == NULL) return NULL_PTR;

    int ret = SUCCESS;

    // Get buffer with rescaled text

    uint8_t *alp_new_buf = NULL;

    uint16_t newH, newW;{

        const size_t len = strlen(p->txt);

        uint16_t W = 0, H = 0; {

            for(size_t i = 0; i < len; ++i){

                const glyph_t *g = p->fnt->glyphs[(size_t)p->txt[i]];

                if(g != NULL){ W += g->w; H = max(H, g->h); }

            }

        }

        uint8_t *alp_buf = malloc(W*H);

        if(alp_buf == NULL) return ALLOC_ERROR;{

            int16_t y = H;

            int16_t x = 0;

            for(size_t i = 0; i < len; ++i){

                const glyph_t *g = p->fnt->glyphs[(size_t)p->txt[i]];

                if(g != NULL){

                    if((ret = glyph_draw_to_alpha_buffer(g, x, y, alp_buf, W, H))) return ret;

                    x += g->w;

                }

            }

        }

        double factor = (double)p->size/(double)H;

        newH = H*factor;

        newW = W*factor;

        alp_new_buf = malloc(newW*newH);

        if(alp_new_buf == NULL) return ALLOC_ERROR;

        for(size_t newy = 0; newy < newH; ++newy){

            size_t y = newy/factor;

            for(size_t newx = 0; newx < newW; ++newx){

                size_t x = newx/factor;

                *(alp_new_buf+newx+newy*newW) = *(alp_buf+x+y*W);

            }

        }

        free(alp_buf);

    }

    // Get initial value of x

    int16_t initx;{

        switch(p->halign){

            case text_halign_left  : initx = p->x         ; break;

            case text_halign_center: initx = p->x - newW/2; break;

            case text_halign_right : initx = p->x - newW  ; break;

            default: return LOGIC_ERROR;

        }

    }

    // Get initial value of y

    int16_t inity;{

        switch(p->valign){

            case text_valign_top   : inity = p->y         ; break;

            case text_valign_center: inity = p->y - newH/2; break;

            case text_valign_bottom: inity = p->y - newH  ; break;

            default: return LOGIC_ERROR;

        }

    }

    // Draw text

    for(int16_t x, y, newy = 0; newy < newH; ++newy){

        y = inity+newy;

        for(int16_t newx = 0; newx < newW; ++newx){

            x = initx+newx;

            if(!(0 <= x && x < graph_get_XRes() &&

                 0 <= y && y < graph_get_YRes())) continue;

            uint8_t a = *(alp_new_buf+newx+newy*newW);

            if(a < ALPHA_THRESHOLD) graph_set_pixel(x,y,p->color);

        }

    }

    free(alp_new_buf);

    return SUCCESS;

}