1 files changed, 252 insertions, 0 deletions
diff --git a/src/escpos/parser.rl b/src/escpos/parser.rl
new file mode 100644
index 0000000..1e045c7
--- /dev/null
+++ b/src/escpos/parser.rl
@@ -0,0 +1,252 @@
+#include "util/ragel/ragel.h"
+#include "stack.h"
+#include "default-font.h"
+#include "parser.h"
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <assert.h>
+#include <err.h>
+
+#define MAX(x, y) (((x) > (y)) ? (x) : (y))
+#define MIN(x, y) (((x) < (y)) ? (x) : (y))
+#define div_round_up(x, y) (1 + ((x - 1) / y))
+
+static const uint8_t SPACING = 1;
+
+struct raster {
+   size_t x, y, wy;
+   struct font font;
+   uint8_t barcode_height;
+   uint8_t barcode_type;
+   enum {
+      UNDERLINE_NONE,
+      UNDERLINE_LIGHT,
+      UNDERLINE_HEAVY,
+   } underline;
+   enum {
+      JUSTIFY_LEFT,
+      JUSTIFY_CENTER,
+      JUSTIFY_RIGHT
+   } justify;
+   bool emphasis;
+   bool double_strike;
+   bool double_width;
+   bool double_height;
+};
+
+static void
+render_chr(struct escpos_canvas *canvas, struct raster *raster, const char chr)
+{
+   assert(canvas && raster);
+   const size_t off = canvas->w * raster->y + raster->x;
+   const struct glyph *glyph = &raster->font.ucs2glyph[MIN((uint8_t)MAX(chr, 0), raster->font.max_ucs)];
+   const uint8_t *data = &raster->font.data[glyph->offset];
+   for (size_t gy = 0; gy < raster->font.height; ++gy) {
+      for (size_t gx = 0; gx < glyph->width; gx += 8) {
+         for (uint8_t b = 0; b < 8; ++b) {
+            const size_t dst = off + (canvas->w * gy + gx + b);
+            assert(dst < canvas->w * canvas->h);
+            canvas->data[dst] = data[div_round_up(glyph->width, 8) * gy + gx] & (1 << (7 - b));
+         }
+      }
+   }
+   raster->x += MIN(glyph->width + SPACING, canvas->w - raster->x);
+   raster->wy = MIN(raster->y + MAX(raster->font.height, 1) - 1, canvas->h);
+}
+
+static void
+init(struct escpos_canvas *canvas, struct raster *raster)
+{
+   assert(canvas && raster);
+   memset(canvas->data, 0, canvas->w * canvas->h);
+   *raster = (struct raster){ .font = _intlfonts_ucs };
+   raster->x = raster->y = raster->wy = 0;
+}
+
+static void
+lfd(const struct escpos_canvas *canvas, struct raster *raster, const uint8_t num)
+{
+   assert(canvas && raster);
+   const size_t lf = (raster->font.height + SPACING) * num;
+   raster->x = 0;
+   raster->y += MIN(lf, canvas->h - raster->y);
+   raster->wy = raster->y + raster->font.height + SPACING;
+}
+
+static void
+cut(const struct escpos_parser *parser, struct escpos_canvas *canvas, struct raster *raster)
+{
+   assert(canvas && raster);
+   assert(raster->wy <= canvas->h);
+
+   if (raster->wy > 0) {
+      parser->write(parser, canvas->data, canvas->w, MIN(canvas->h, raster->wy));
+      memset(canvas->data, 0, canvas->w * canvas->h);
+      raster->x = raster->y = raster->wy = 0;
+   }
+}
+
+%%{
+   machine escpos_parser;
+   include escpos_stack "stack.rl";
+   variable p ragel.p;
+   variable pe ragel.pe;
+   variable eof ragel.eof;
+   write data noerror nofinal;
+
+   action init {
+      puts("init");
+      init(&parser->canvas, &raster);
+   }
+
+   action lfd {
+      fprintf(stderr, "lfd %d\n", stack_get_num(&stack));
+      lfd(&parser->canvas, &raster, stack_get_num(&stack));
+   }
+
+   action lfv {
+      fprintf(stderr, "lfv %d\n", stack_get_num(&stack));
+      const size_t lf = (raster.font.height + SPACING) * stack_get_num(&stack);
+      raster.x = 0;
+      raster.y -= MIN(lf, raster.y);
+      raster.wy = raster.y + raster.font.height + SPACING;
+   }
+
+   action print_mode {
+      fprintf(stderr, "print-mode: %d\n", stack_get_num(&stack));
+      enum {
+         MODE_FONTA = 1<<0,
+         MODE_FONTB = 1<<1,
+         MODE_EMPHASIS = 1<<2,
+         MODE_DOUBLE_HEIGHT = 1<<3,
+         MODE_DOUBLE_WIDTH = 1<<4,
+         MODE_UNDERLINE = 1<<5,
+      };
+      const uint8_t mode = stack_get_num(&stack);
+      raster.emphasis = (mode & MODE_EMPHASIS);
+      raster.double_width = (mode & MODE_DOUBLE_HEIGHT);
+      raster.double_width = (mode & MODE_DOUBLE_WIDTH);
+      raster.underline = (mode & MODE_UNDERLINE);
+   }
+
+   action underline {
+      fprintf(stderr, "underline %d\n", stack_get_num(&stack));
+      raster.underline = stack_get_num(&stack);
+   }
+
+   action cut {
+      fprintf(stderr, "cut %d\n", stack_get_num(&stack));
+      cut(parser, &parser->canvas, &raster);
+   }
+
+   action emphasis {
+      fprintf(stderr, "emphasis %d\n", stack_get_num(&stack));
+      raster.emphasis = stack_get_num(&stack);
+   }
+
+   action double_strike {
+      fprintf(stderr, "double-strike %d\n", stack_get_num(&stack));
+      raster.double_strike = stack_get_num(&stack);
+   }
+
+   action font {
+      fprintf(stderr, "font %d\n", stack_get_num(&stack));
+      // XXX: have only one font
+   }
+
+   action justify {
+      fprintf(stderr, "justify %d\n", stack_get_num(&stack));
+      raster.justify = stack_get_num(&stack);
+   }
+
+   action barcode_height {
+      fprintf(stderr, "barcode-height %d\n", stack_get_num(&stack));
+      raster.barcode_height = stack_get_num(&stack);
+   }
+
+   action barcode_type {
+      fprintf(stderr, "barcode-type %d\n", stack_get_num(&stack));
+      raster.barcode_type = stack_get_num(&stack);
+   }
+
+   action barcode_str {
+      fprintf(stderr, "barcode-str %s\n", (char*)stack_get_str(&stack)->data);
+      // XXX: raster barcode
+   }
+
+   action syntax_err {
+      ragel_throw_error(&ragel, "malformed input (machine failed here or in next expression)");
+   }
+
+   action text {
+      putc(fc, stderr);
+      render_chr(&parser->canvas, &raster, fc);
+   }
+
+   action line {
+      fputs("\\n", stderr);
+      ragel_advance_line(&ragel);
+      lfd(&parser->canvas, &raster, 1);
+   }
+
+   # Constants
+   LF = 0x0A; # Line Feed
+   ESC = 0x1B; # Escape
+   GS = 0x1D; # Group Separator
+
+   # Commands
+   # https://reference.epson-biz.com/modules/ref_escpos/index.php?content_id=72
+   # TODO: Implement rest
+   init = ESC '@' %init;
+   linefeed = LF %line | ESC :>> (('d' stack_num) %lfd | ('v' stack_num) %lfv);
+   print_mode = ESC '!' stack_num %print_mode;
+   underline = ESC '-' stack_num %underline;
+   cut = GS 'V' stack_num 0x03 %cut;
+   emphasis = ESC 'E' stack_num %emphasis;
+   double_strike = ESC 'G' stack_num %double_strike;
+   font = ESC 'M' stack_num %font;
+   justify = ESC 'a' stack_str %justify;
+   barcode_height = GS 'h' stack_num %barcode_height;
+   barcode = ESC 'k' stack_num %barcode_type stack_str %barcode_str;
+
+   # Obsolete commands
+   # https://reference.epson-biz.com/modules/ref_escpos/index.php?content_id=74
+   # TODO: Implement
+
+   # Logic
+   cmd = (init | linefeed | print_mode | underline | cut | emphasis | double_strike | font | justify | barcode);
+   main := (cmd | TEXT $text)* $!syntax_err;
+}%%
+
+bool
+escpos_parser_parse(struct escpos_parser *parser, const char *name)
+{
+   int cs;
+   %% write init;
+
+   (void)escpos_parser_en_main;
+   assert(parser);
+   assert(parser->read);
+   assert(parser->write);
+
+   char var[256];
+   struct stack stack = { .var.buf.mem = { .data = var, .len = sizeof(var) } };
+   struct ragel ragel = { .name = name, .lineno = 1 };
+
+   struct raster raster;
+   init(&parser->canvas, &raster);
+
+   struct escpos_mem window = parser->window;
+   for (bool eof = false; !ragel.error && !eof;) {
+      const size_t bytes = parser->read(parser, window.data, window.len);
+      const struct ragel_mem input = { .data = window.data, .end = (char*)window.data + bytes, .binary = true };
+      ragel_feed_input(&ragel, (eof = (bytes < window.len)), &input);
+      %% write exec;
+   }
+
+   if (!ragel.error)
+      cut(parser, &parser->canvas, &raster);
+
+   return !ragel.error;
+}