#include "dryos.h"
#include "bmp.h"
#include "beep.h"
#include "rbf_font.h"

/* here some macros to wrap the CHDK functions for ML code */
#define FG_COLOR(f) FONT_FG(f)
#define BG_COLOR(f) FONT_BG(f)
#define MAKE_COLOR(fg,bg) FONT(0,fg,bg)

#define draw_char(x,y,c,h) do{}while(0)

static int rbf_font_load(char *file, font* f, int maxchar);
static inline int rbf_font_height(font *rbf_font);
static inline int rbf_char_width(font *rbf_font, int ch);

//-------------------------------------------------------------------
static int RBF_HDR_MAGIC1 = 0x0DF00EE0;
static int RBF_HDR_MAGIC2 = 0x00000003;

struct font font_dynamic[MAX_DYN_FONTS+1];
static char *dyn_font_name[MAX_DYN_FONTS+1];
uint32_t dyn_fonts = 0;

//-------------------------------------------------------------------

static font *new_font() {
    // allocate font from cached memory
    font *f = malloc(sizeof(font));
    if (f) {
        memset(f,0,sizeof(font));      // wipe memory
        // return address in cached memory
        return f;
    }

    // memory not allocated ! should probably do something else in this case ?
    return 0;
}

uint32_t font_by_name(char *file, uint32_t fg_color, uint32_t bg_color)
{
    /* check if this font was already loaded */
    for(int pos = 0; pos < (int)dyn_fonts; pos++)
    {
        if(!strcmp(file, dyn_font_name[pos]))
        {   
            /* yeah, so return a new specifier for this id */
            return FONT_DYN(pos, fg_color, bg_color);
        }
    }
    
    /* too many fonts loaded, return default font */
    if(dyn_fonts >= MAX_DYN_FONTS)
    {
        beep();
        bmp_printf(FONT_CANON, 0, 0, "Too many fonts");
        return FONT_CANON;
    }
    
    /* was not loaded, try to load */
    char filename[128];
    snprintf(filename, sizeof(filename), "ML/FONTS/%s.RBF", file);
    
    uint32_t size;
    if((FIO_GetFileSize( filename, &size ) != 0) || (size == 0))
    {
        /* failed to load, return default font */
        beep();
        bmp_printf(FONT_CANON, 0, 0, "%s not found", file);
        return FONT_CANON;
    }
    
    void *font = new_font();
    
    /* load the font here */
    if(!rbf_font_load(filename, font, 0))
    {
        bmp_printf(FONT_CANON, 0, 0, "%s not loaded", file);
        free(font);
        return FONT_CANON;
    }

    /* now updated cached font name (not filename) */
    dyn_font_name[dyn_fonts] = malloc(strlen(filename) + 1);
    strcpy(dyn_font_name[dyn_fonts], file);
    
    /* and measure font sizes */
    font_dynamic[dyn_fonts].bitmap = font;
    font_dynamic[dyn_fonts].height = rbf_font_height((void*)font_dynamic[dyn_fonts].bitmap);
    font_dynamic[dyn_fonts].width = rbf_char_width((void*)font_dynamic[dyn_fonts].bitmap, '0');
    dyn_fonts++;

    return FONT_DYN(dyn_fonts - 1, fg_color, bg_color);
}

static void alloc_cTable(font *f) {

    // Calculate additional values for font
    f->width = 8 * f->hdr.charSize / f->hdr.height;
    f->charCount = f->hdr.charLast - f->hdr.charFirst + 1;

    // set width table to default value
    memset(f->wTable, f->width, 256);
    
    // allocate cTable memory

    // If existing data has been allocated then we are re-using the font data
    // See if it the existing cTable data is large enough to hold the new font data
    // If not free it so new memory will be allocated
    if ((f->cTable != 0) && (f->cTableSizeMax < (f->charCount*f->hdr.charSize))) {
        free(f->cTable);              // free the memory
        f->cTable = 0;                // clear pointer so new memory is allocated
        f->cTableSizeMax = 0;
    }

    // Allocated memory if needed
    if (f->cTable == 0) {
        // Allocate memory from cached pool
        int size = f->charCount*f->hdr.charSize;
        f->cTable = malloc(size);

        // save size
        f->cTableSize = f->charCount*f->hdr.charSize;
        if (f->cTableSizeMax == 0) f->cTableSizeMax = f->cTableSize;    // Save actual size allocated
    }
}

//-------------------------------------------------------------------
// Return address of 'character' data for specified font & char
static inline char* FAST rbf_font_char(font* f, int ch)
{
    if (f && (ch >= f->hdr.charFirst) && (ch <= f->hdr.charLast))
    {
        return &f->cTable[(ch-f->hdr.charFirst)*f->hdr.charSize];
    }

    return 0;
}
//-------------------------------------------------------------------
// Read data from SD file using uncached buffer and copy to cached
// font memory
static int font_read(FILE* fd, unsigned char *dest, int len)
{
    // Return actual bytes read
    int bytes_read = 0;

    unsigned char *ubuffer = fio_malloc(len);
    
    if (ubuffer)
    {
        // Read block and copy to dest
        bytes_read += FIO_ReadFile(fd, ubuffer, len);
        memcpy(dest, ubuffer, len);
        fio_free(ubuffer);
    }

    return bytes_read;
}
//-------------------------------------------------------------------
// Load from from file. If maxchar != 0 limit charLast (for symbols)
static int rbf_font_load(char *file, font* f, int maxchar)
{
    int i;

    // make sure the font has been allocated
    if (f == 0)
    {
        return 0;
    }

    // open file (can't use fopen here due to potential conflict FsIoNotify crash)
    FILE *fd = FIO_OpenFile(file, O_RDONLY | O_SYNC);
    if( fd == INVALID_PTR )
    {
        return 0;
    }
    
    // read header
    i = font_read(fd, (unsigned char*)&(f->hdr), sizeof(font_hdr));

    // check size read is correct and magic numbers are valid
    if ((i != sizeof(font_hdr)) || (f->hdr.magic1 != RBF_HDR_MAGIC1) || (f->hdr.magic2 != RBF_HDR_MAGIC2))
    {
        return 0;
    }
    
    if (maxchar != 0)
    {
        f->hdr.charLast = maxchar;
    }

    alloc_cTable(f);

    // read width table (using uncached buffer)
    FIO_SeekFile(fd, f->hdr._wmapAddr, SEEK_SET);
    font_read(fd, (unsigned char*)&f->wTable[f->hdr.charFirst], f->charCount);

    // read cTable data (using uncached buffer)
    FIO_SeekFile(fd, f->hdr._cmapAddr, SEEK_SET);
    font_read(fd, (unsigned char*)f->cTable, f->charCount*f->hdr.charSize);

    FIO_CloseFile(fd);

    return 1;
}

//-------------------------------------------------------------------
static inline int rbf_font_height(font *rbf_font) {
    return rbf_font->hdr.height;
}
//-------------------------------------------------------------------
static inline int rbf_char_width(font *rbf_font, int ch) {
    return rbf_font->wTable[ch];
}

//-------------------------------------------------------------------
int rbf_str_width(font *rbf_font, const char *str) {
    int l=0;
    int maxl = 0;

    // Calculate how long the string is in pixels
    // and return the length of the longest line
    while (*str)
    {
        if (*str == '\n')
        {
            maxl = MAX(l, maxl);
            l = 0;
        }
        else
        {
            l += rbf_char_width(rbf_font, *str);
        }
        str++;
    }
    maxl = MAX(l, maxl);

    return maxl;
}

int rbf_str_clipped_width(font *rbf_font, const char *str, int maxlen) {
    int l = 0;
    // Calculate how long the string is in pixels (possibly clipped to 'maxlen')
    while (*str && l+rbf_char_width(rbf_font, *str)<=maxlen)
        l+=rbf_char_width(rbf_font, *str++);

    return l;
}

int rbf_strlen_clipped(font *rbf_font, const char *str, int maxlen) {
    int l = 0;
    // Calculate how long the string is in characters (possibly clipped to 'maxlen')
    char* str0 = (char*) str;
    while (*str && l+rbf_char_width(rbf_font, *str)<=maxlen)
        l+=rbf_char_width(rbf_font, *str++);

    return str - str0;
}

//-------------------------------------------------------------------
static void FAST font_draw_char(font *rbf_font, int x, int y, char *cdata, int width, int height, int pixel_width, int fontspec) {
    int xx, yy;
    uint8_t * bmp = bmp_vram();
    int fg = FG_COLOR(fontspec);
    int bg = BG_COLOR(fontspec);
    
    // draw pixels for font character
    if (cdata)
    {
        for (yy=0; yy<height; ++yy)
        {
            if (y+yy <= BMP_H_MINUS || y+yy >= BMP_H_PLUS)
            {
                break;
            }
            for (xx=0; xx<pixel_width; ++xx)
            {
                bmp_putpixel_fast(bmp, x+xx, y+yy, (cdata[yy*width/8+xx/8] & (1<<(xx%8))) ? fg : bg);
            }
        }
    }
}

static void FAST font_draw_char_shadow(font *rbf_font, int x, int y, char *cdata, int width, int height, int pixel_width, int fontspec) {
    int xx, yy;
    uint8_t * bmp = bmp_vram();
    int fg = FG_COLOR(fontspec);
    int bg = BG_COLOR(fontspec);
    
    // draw pixels for font character
    if (cdata)
    {
        for (yy=0; yy<height; ++yy)
        {
            if (y+yy <= BMP_H_MINUS || y+yy >= BMP_H_PLUS)
            {
                break;
            }
            for (xx=0; xx<pixel_width; ++xx)
            {
                int px = (cdata[yy*width/8+xx/8] & (1<<(xx%8)));
                if (px)
                {
                    bmp_putpixel_fast(bmp, x+xx, y+yy, fg);
                    
                    /* shadow: background pixels are only drawn near a foreground pixel */
                    /* heuristic: usually there are much less fg pixels than bg, so it makes sense to look for neighbours here */
                    for (int xxx = MAX(xx-1, 0); xxx <= MIN(xx+1, pixel_width-1); xxx++)
                    {
                        for (int yyy = MAX(yy-1, 0); yyy <= MIN(yy+1, height-1); yyy++)
                        {
                            int pxx = (cdata[yyy*width/8+xxx/8] & (1<<(xxx%8)));
                            if (!pxx)
                            {
                                bmp_putpixel_fast(bmp, x+xxx, y+yyy, bg);
                            }
                        }
                    }
                }
            }
        }
    }
}

//-------------------------------------------------------------------
static int FAST rbf_draw_char(font *rbf_font, int x, int y, int ch, int fontspec) {
    // Get char data pointer
    char* cdata = rbf_font_char(rbf_font, ch);
    
    if (!rbf_font->cTable)
        bfnt_draw_char(ch, x, y, FG_COLOR(fontspec), BG_COLOR(fontspec));
    else if (fontspec & SHADOW_MASK)
        font_draw_char_shadow(rbf_font, x, y, cdata, rbf_font->width, rbf_font->hdr.height, rbf_font->wTable[ch], fontspec);
    else
        font_draw_char(rbf_font, x, y, cdata, rbf_font->width, rbf_font->hdr.height, rbf_font->wTable[ch], fontspec);

    return rbf_font->wTable[ch];
}


//-------------------------------------------------------------------
// Draw a string colored 'c1' with the character at string-position 'c' colored 'c2'.
static int rbf_draw_string_c(font *rbf_font, int x, int y, const char *str, int fontspec1, int c, int fontspec2) {
     int l=0, i=0;

     while (*str) {
          if (*str == '\n')
          {
              l = 0;
              y += rbf_font->hdr.height;
              str++;
              i++;
              continue;
          }
          l+=rbf_draw_char(rbf_font, x+l, y, *str++, (i==c)?fontspec1:fontspec2);
          ++i;
     }
     return l;
}

//-------------------------------------------------------------------
static int rbf_draw_string_simple(font *rbf_font, int x, int y, const char *str, int fontspec) {
    return rbf_draw_string_c(rbf_font, x, y, str, fontspec, -1, fontspec);
}

//-------------------------------------------------------------------
static int rbf_draw_clipped_string(font *rbf_font, int x, int y, const char *str, int fontspec, int maxlen)
{
    int i = 0;
    int l = 0;
    
    int justified = (fontspec & FONT_ALIGN_MASK) == FONT_ALIGN_JUSTIFIED;
    
    if (justified)
    {
        int should_fill = !(fontspec & SHADOW_MASK);
        int bg = FONT_BG(fontspec);
        int len = maxlen;
        int space = len - rbf_str_width(rbf_font, str);
        
        /* divide the space across the chars: a space character can accept 5 times more stretch space than a regular letter */
        /* first non-letter (indent) can't be stretched (to render bullet points correctly) */
        int bins = 0;
        char* c = (char*) str;
        int indent = 1;
        while (*c)
        {
            if (*c != ' ' && *c != '*') indent = 0;
            bins += indent ? 0 : space < 0 ? 1 : *c == ' ' ? 10 : 2;
            c++;
        }
        
        /* use Bresenham line-drawing algorithm to divide space with integer-only math */
        /* http://en.wikipedia.org/wiki/Bresenham%27s_line_algorithm#Algorithm_with_Integer_Arithmetic */
        /* x: from 0 to bins */
        /* y: space accumulated (from 0 to space) */
        int dx = bins;
        int dy = ABS(space);
        
        /* if it requires too much stretching, give up */
        if (dy > dx)
            dy = 0;
        
        int D = 2*dy - dx;

        // Draw chars from string up to max pixel length
        indent = 1;
        while (*str && l+rbf_char_width(rbf_font, *str)<=maxlen)
        {
            l += rbf_draw_char(rbf_font, x+l, y, *str, fontspec);
            
            /* Bresenham step */
            int l0 = l;
            if (*str != ' ' && *str != '*') indent = 0;
            int repeat = indent ? 0 : space < 0 ? 1 : *str == ' ' ? 10 : 2;
            for (int i = 0; i < repeat; i++)
            {
                if (D > 0)
                {
                    l += SGN(space);
                    D = D + (2*dy - 2*dx);
                }
                else
                {
                    D = D + 2*dy;
                }
            }
            
            if (should_fill && l > l0)
            {
                bmp_fill(bg, x+l0, y, l-l0, rbf_font->hdr.height);
            }
            
            i++; str++;
        }
    }
    else
    {
        // Draw chars from string up to max pixel length
        while (*str && l+rbf_char_width(rbf_font, *str)<=maxlen)
        {
            l+=rbf_draw_char(rbf_font, x+l, y, *str++, fontspec);
            i++;
        }
    }
    return l;
}

//-------------------------------------------------------------------
static int rbf_draw_string_single_line(font *rbf_font, int x, int y, const char *str, int fontspec, int maxlen) {
    
    /* how much space do we have to draw the string? */
    int len = maxlen;
    
    // Calulate amount of padding needed
    int padding = len - rbf_str_clipped_width(rbf_font, str, len);

    /* is that padding on the left? on the right? or both? */
    int padding_left = 0;
    int padding_right = 0;
    
    switch (fontspec & FONT_ALIGN_MASK)
    {
        case FONT_ALIGN_LEFT:
            padding_right = padding;
            break;
        
        case FONT_ALIGN_CENTER:
            x -= len/2;
            padding_left = padding/2;
            padding_right = padding - padding/2;
            break;
        
        case FONT_ALIGN_RIGHT:
            padding_left = padding;
            x -= len;
            break;
        
        case FONT_ALIGN_JUSTIFIED:
            padding_left = 0;
            padding_right = 0;
    }
    
    int bg = FONT_BG(fontspec);
    int should_fill = fontspec & FONT_ALIGN_FILL;

    // Fill left padding with background color
    if (should_fill && padding_left)
        bmp_fill(bg, x, y, padding_left, rbf_font->hdr.height);

    // Draw chars
    rbf_draw_clipped_string(rbf_font, x + padding_left, y, str, fontspec, len - padding_right - padding_left);

    // Fill right padding with background color
    if (should_fill && padding_right)
        bmp_fill(bg, x+len-padding_right, y, padding_right, rbf_font->hdr.height);

    return len;
}

int rbf_draw_string(font *rbf_font, int x, int y, const char *str, int fontspec) {

    /* how much space do we have to draw the string? */
    int len = FONT_GET_TEXT_WIDTH(fontspec);

    /* choose some reasonable defaults for text width, if it's not specified */
    if (len == 0)
    {
        if ((fontspec & FONT_ALIGN_MASK) == FONT_ALIGN_LEFT && (fontspec & FONT_ALIGN_FILL) == 0)
        {
            /* no fancy alignment */
            return rbf_draw_string_simple(rbf_font, x, y, str, fontspec);
        }
        else
        {
            /* use natural string length */
            len = rbf_str_width(rbf_font, str);
        }
    }

    char* start = (char*) str;
    char* end = start;

    /* for each line in string */
    while (*start)
    {
        /* where does this line end? */
        while (*end && *end != '\n')
            end++;
        
        /* chop the string here */
        char old = *end;
        *end = 0;
        
        /* draw this line */
        rbf_draw_string_single_line(rbf_font, x, y, start, fontspec, len);
        
        /* finished? */
        if (old == 0)
            break;
        
        /* undo chopping */
        *end = old;
        
        /* okay, let's go to next line */
        y += rbf_font->hdr.height;
        start = end = end+1;
    }
    
    return len;
}


/* for compatibility with existing code */
struct font font_small;
struct font font_med;
struct font font_med_large;
struct font font_large;
struct font font_canon;

/* must be called before menu_init, otherwise it can't measure strings */
void _load_fonts()
{
    /* tolerate multiple calls, but only run the first */
    static int fonts_loaded = 0;
    if (fonts_loaded) return;
    fonts_loaded = 1;
    
    /* fake font for Canon font backend, with the same metrics */
    font * canon_font = new_font();
    canon_font->hdr.height = 40;
    for (int i = 0; i < 256; i++)
        canon_font->wTable[i] = bfnt_char_get_width(i);

    /* use Canon font as fallback */
    /* (will be overwritten when loading named fonts) */
    for (int i = 0; i <= MAX_DYN_FONTS; i++)
    {
        font_dynamic[i].bitmap = (void*) canon_font;
        font_dynamic[i].height = 40;
        font_dynamic[i].width = rbf_char_width((void*)font_dynamic[i].bitmap, '0');
    }

    /* load some fonts */
    font_by_name("term12", COLOR_BLACK, COLOR_WHITE);
    font_by_name("term20", COLOR_BLACK, COLOR_WHITE);
    #ifdef CONFIG_LOW_RESOLUTION_DISPLAY
    font_by_name("arghlf22", COLOR_BLACK, COLOR_WHITE);
    #else
    font_by_name("argnor23", COLOR_BLACK, COLOR_WHITE);
    #endif
    font_by_name("argnor28", COLOR_BLACK, COLOR_WHITE);
    font_by_name("argnor32", COLOR_BLACK, COLOR_WHITE);

    font_small = *fontspec_font(FONT_SMALL);
    font_med = *fontspec_font(FONT_MED);
    font_med_large = *fontspec_font(FONT_MED_LARGE);
    font_large = *fontspec_font(FONT_LARGE);
    font_canon = *fontspec_font(FONT_CANON);
}