`nx_mailpiece.nx` source

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1// nx_mailpiece.nx -- PHYSICAL MAIL COMPOSITION (rung 2 of Nishi Mail to SOTA). Composes a print-ready
2// postcard as an RGB raster and writes it as PNG (preview + the exact bitmap the sovereign print path
3// nx_img_print -> PWG/URF -> IPP feeds to a real printer). NISHI-POSTCARD: 6x4in @300dpi = 1800x1200.
4// FRONT = greeting design (accent bleed + cream panel + centered title). BACK = USPS layout: message on
5// the left, a vertical divider, the recipient address block in the address zone on the right, a stamp
6// (indicia) box top-right, and the lower-right IMb barcode clear zone kept blank by construction.
7// Sovereign: pure integer raster ops + the sovereign 8x8 font; no 3rd party. Last-mile (print vs carrier)
8// is the next rung. Commands: postcard <front.png> <back.png> <greeting> <message> <recipient> <line1> <city> <region> <postal> ; argless = selftest.
9// expect_exit: 0  license_tier: ORIGINAL
10import "nx_syscalls.nx"
11import "nx_font8x8.nx"
12import "nx_png_write.nx"
13const K_MAGIC_1800: i64 = 1800
14const K_MAGIC_1200: i64 = 1200
15const K_MAGIC_1080: i64 = 1080
16const K_MAGIC_1040: i64 = 1040
17const K_MAGIC_1560: i64 = 1560
18const K_MAGIC_1720: i64 = 1720
19const K_MAGIC_1587: i64 = 1587
20const K_MAGIC_2550: i64 = 2550
21const K_MAGIC_3300: i64 = 3300
22const K_MAGIC_1099: i64 = 1099
23const K_MAGIC_1102: i64 = 1102
24const K_MAGIC_2199: i64 = 2199
25const K_MAGIC_2202: i64 = 2202
26const K_MAGIC_1250: i64 = 1250
27const K_MAGIC_1380: i64 = 1380
28const K_MAGIC_1950: i64 = 1950
29const K_MAGIC_2500: i64 = 2500
30const K_MAGIC_2590: i64 = 2590
31const K_MAGIC_3140: i64 = 3140
32const K_MAGIC_2850: i64 = 2850
33const K_MAGIC_1238: i64 = 1238
34const K_MAGIC_2620: i64 = 2620
35const K_MAGIC_2760: i64 = 2760
36const K_MAGIC_2640: i64 = 2640
37const K_MAGIC_1612: i64 = 1612
38const K_MAGIC_1088: i64 = 1088
39const K_MAGIC_3150: i64 = 3150
40const K_MAGIC_2175: i64 = 2175
41const K_MAGIC_1575: i64 = 1575
42const K_MAGIC_2050: i64 = 2050
43const K_MAGIC_1300: i64 = 1300
44const K_MAGIC_1890: i64 = 1890
45
46func slen(s: *u8) -> i64 { var n: i64 = 0; while s[n] != (0 as u8) { n = n + 1 } return n }
47func p(s: *u8) -> i64 { sys_write(1, s, slen(s)); return 0 }
48func pn(v: i64) -> i64 {
  var m: i64 = v; if m < 0 { p("-" as *u8); m = 0 - m }
  let t: *u8 = sys_mmap(24); var k: i64 = 0; if m == 0 { t[0] = 48 as u8; k = 1 }
  while m > 0 { t[k] = (48 + (m % 10)) as u8; m = m / 10; k = k + 1 }
  let o: *u8 = sys_mmap(24); var i: i64 = 0; while i < k { o[i] = t[k-1-i]; i = i + 1 } sys_write(1, o, k); return 0
53}
54func seq(a: *u8, b: *u8) -> i64 {
  var i: i64 = 0
  while a[i] != (0 as u8) { if a[i] != b[i] { return 0 } i = i + 1 }
  if b[i] != (0 as u8) { return 0 }
  return 1
59}
60
61// ---- raster primitives (canvas = W*H*3 RGB, origin top-left) ----
62func set_px(rgb: *u8, W: i64, H: i64, x: i64, y: i64, r: i64, g: i64, b: i64) -> i64 {
  if x < 0 { return 0 }
  if y < 0 { return 0 }
  if x >= W { return 0 }
  if y >= H { return 0 }
  let o: i64 = (y * W + x) * 3
  rgb[o] = r as u8; rgb[o+1] = g as u8; rgb[o+2] = b as u8
  return 0
70}
71func fill_rect(rgb: *u8, W: i64, H: i64, x0: i64, y0: i64, x1: i64, y1: i64, r: i64, g: i64, b: i64) -> i64 {
  var y: i64 = y0
  while y <= y1 { var x: i64 = x0; while x <= x1 { set_px(rgb, W, H, x, y, r, g, b); x = x + 1 } y = y + 1 }
  return 0
75}
76func rect_outline(rgb: *u8, W: i64, H: i64, x0: i64, y0: i64, x1: i64, y1: i64, th: i64, r: i64, g: i64, b: i64) -> i64 {
  fill_rect(rgb, W, H, x0, y0, x1, y0 + th, r, g, b)
  fill_rect(rgb, W, H, x0, y1 - th, x1, y1, r, g, b)
  fill_rect(rgb, W, H, x0, y0, x0 + th, y1, r, g, b)
  fill_rect(rgb, W, H, x1 - th, y0, x1, y1, r, g, b)
  return 0
82}
83// draw one 8x8 glyph scaled by sc; bit 0 (LSB) = leftmost column (per nx_font8x8)
84func draw_glyph(rgb: *u8, W: i64, H: i64, tbl: *u8, ch: i64, x: i64, y: i64, sc: i64, r: i64, g: i64, b: i64) -> i64 {
  if ch < 32 { return 0 }
  if ch > 126 { return 0 }
  let base: i64 = (ch - 32) * 8
  var row: i64 = 0
  while row < 8 {
      let bits: i64 = tbl[base + row] as i64
      var col: i64 = 0
      while col < 8 {
          if ((bits >> col) & 1) == 1 {
              var dy: i64 = 0
              while dy < sc { var dx: i64 = 0; while dx < sc { set_px(rgb, W, H, x + col*sc + dx, y + row*sc + dy, r, g, b); dx = dx + 1 } dy = dy + 1 }
          }
          col = col + 1
      }
      row = row + 1
  }
  return 0
102}
103// draw a NUL-terminated string; per-char advance = 8*sc + sp; returns end x
104func draw_text(rgb: *u8, W: i64, H: i64, tbl: *u8, s: *u8, x: i64, y: i64, sc: i64, sp: i64, r: i64, g: i64, b: i64) -> i64 {
  var i: i64 = 0
  var cx: i64 = x
  while s[i] != (0 as u8) { draw_glyph(rgb, W, H, tbl, s[i] as i64, cx, y, sc, r, g, b); cx = cx + 8*sc + sp; i = i + 1 }
  return cx
109}
110// word-wrap a string inside [x, x+maxw]; returns final y
111func draw_wrap(rgb: *u8, W: i64, H: i64, tbl: *u8, s: *u8, x: i64, y: i64, sc: i64, maxw: i64, r: i64, g: i64, b: i64) -> i64 {
  let cw: i64 = 8*sc + sc
  let lh: i64 = 8*sc + sc*3
  var cx: i64 = x
  var cy: i64 = y
  var i: i64 = 0
  while s[i] != (0 as u8) {
      var j: i64 = i
      while s[j] != (0 as u8) { if s[j] == (32 as u8) { break } j = j + 1 }
      let wl: i64 = j - i
      if cx + wl*cw > x + maxw { cx = x; cy = cy + lh }
      var k: i64 = i
      while k < j { draw_glyph(rgb, W, H, tbl, s[k] as i64, cx, cy, sc, r, g, b); cx = cx + cw; k = k + 1 }
      i = j
      while s[i] == (32 as u8) { cx = cx + cw; i = i + 1 }
      if cx > x + maxw { cx = x; cy = cy + lh }
  }
  return cy
129}
130func cpy(dst: *u8, off: i64, s: *u8) -> i64 { var i: i64 = 0; while s[i] != (0 as u8) { dst[off+i] = s[i]; i = i + 1 } return off + i }
131func text_w(s: *u8, sc: i64, sp: i64) -> i64 { return slen(s) * (8*sc + sp) }
132func fsize(path: *u8) -> i64 { let fd: i64 = sys_openat_rd(path); if fd < 0 { return 0 - 1 } let n: i64 = sys_lseek(fd, 0, 2); sys_close(fd); return n }
133
134// ---- compose a postcard (front + back) ----
135func compose(fp: *u8, bp: *u8, greeting: *u8, message: *u8, recipient: *u8, line1: *u8, city: *u8, region: *u8, postal: *u8) -> i64 {
  let W: i64 = K_MAGIC_1800
  let H: i64 = K_MAGIC_1200
  let tbl: *u8 = font8x8_table()
139
  // ===== FRONT =====
  let front: *u8 = sys_mmap(W * H * 3)
  fill_rect(front, W, H, 0, 0, W-1, H-1, 34, 110, 140)          // teal full bleed
  fill_rect(front, W, H, 70, 70, W-71, H-71, 250, 247, 240)     // cream panel (safe area)
  rect_outline(front, W, H, 96, 96, W-97, H-97, 5, 190, 60, 70) // warm accent inset border
  let gsc: i64 = 9
  let gx: i64 = (W - text_w(greeting, gsc, gsc)) / 2
  draw_text(front, W, H, tbl, greeting, gx, 470, gsc, gsc, 34, 36, 46)
  let sub: *u8 = "a note from afar"
  let ssc: i64 = 4
  draw_text(front, W, H, tbl, sub, (W - text_w(sub, ssc, ssc)) / 2, 690, ssc, ssc, 190, 60, 70)
  nx_png_write_rgb(fp, front, W, H)
152
  // ===== BACK (address side) =====
  let back: *u8 = sys_mmap(W * H * 3)
  fill_rect(back, W, H, 0, 0, W-1, H-1, 250, 247, 240)          // cream
  fill_rect(back, W, H, 898, 120, 902, K_MAGIC_1080, 60, 62, 72)        // vertical divider
  // LEFT: the message, wrapped
  draw_wrap(back, W, H, tbl, message, 90, 180, 4, 740, 34, 36, 46)
  draw_text(back, W, H, tbl, "Nishi Mail - on your own hardware", 90, K_MAGIC_1040, 2, 2, 130, 130, 142)
  // RIGHT: stamp (indicia) box top-right
  rect_outline(back, W, H, K_MAGIC_1560, 90, K_MAGIC_1720, 250, 4, 150, 150, 162)
  draw_text(back, W, H, tbl, "STAMP", K_MAGIC_1587, 155, 2, 2, 150, 150, 162)
  // recipient address block in the address zone
  let asc: i64 = 4
  draw_text(back, W, H, tbl, recipient, 1000, 520, asc, asc, 34, 36, 46)
  draw_text(back, W, H, tbl, line1, 1000, 590, asc, asc, 34, 36, 46)
  let cl: *u8 = sys_mmap(256)
  var o: i64 = 0
  o = cpy(cl, o, city); cl[o] = 44 as u8; o = o + 1; cl[o] = 32 as u8; o = o + 1
  o = cpy(cl, o, region); cl[o] = 32 as u8; o = o + 1; o = cpy(cl, o, postal); cl[o] = 0 as u8
  draw_text(back, W, H, tbl, cl, 1000, 660, asc, asc, 34, 36, 46)
  // lower-right IMb barcode clear zone (x 940..1720, y 1000..1120) left blank by construction
  nx_png_write_rgb(bp, back, W, H)
174
  p("NISHI-POSTCARD front=" as *u8); p(fp); p(" back=" as *u8); p(bp)
  p(" size=1800x1200 recipient=" as *u8); p(recipient); p("\n" as *u8)
  return 0
178}
179
180// ===== NISHI-ENVELOPE: letter (8.5x11 @300dpi, tri-fold, window-positioned address) + the No.10 face =====
181// args bundle a: [0]=out.png [1]=sender [2]=recipient [3]=line1 [4]=city [5]=region [6]=postal [7]=body
182func compose_letter(a: *i64) -> i64 {
  let W: i64 = K_MAGIC_2550
  let H: i64 = K_MAGIC_3300
  let tbl: *u8 = font8x8_table()
  let pg: *u8 = sys_mmap(W * H * 3)
  fill_rect(pg, W, H, 0, 0, W-1, H-1, 255, 255, 255)
  // sender block top-left (return address zone)
  draw_text(pg, W, H, tbl, a[1] as *u8, 300, 240, 3, 3, 34, 36, 46)
  draw_text(pg, W, H, tbl, "via Nishi Mail", 300, 320, 2, 2, 130, 130, 142)
  // recipient block in the No.10 WINDOW ZONE (shows through when tri-folded: ~1in left, ~2.2in from top)
  let cl: *u8 = sys_mmap(256)
  var o: i64 = 0
  o = cpy(cl, o, a[4] as *u8); cl[o] = 44 as u8; o = o + 1; cl[o] = 32 as u8; o = o + 1
  o = cpy(cl, o, a[5] as *u8); cl[o] = 32 as u8; o = o + 1; o = cpy(cl, o, a[6] as *u8); cl[o] = 0 as u8
  draw_text(pg, W, H, tbl, a[2] as *u8, 300, 660, 4, 4, 34, 36, 46)
  draw_text(pg, W, H, tbl, a[3] as *u8, 300, 730, 4, 4, 34, 36, 46)
  draw_text(pg, W, H, tbl, cl, 300, 800, 4, 4, 34, 36, 46)
  // tri-fold tick marks at 1/3 and 2/3 (y=1100, y=2200)
  fill_rect(pg, W, H, 0, K_MAGIC_1099, 48, K_MAGIC_1102, 190, 190, 198)
  fill_rect(pg, W, H, W-49, K_MAGIC_1099, W-1, K_MAGIC_1102, 190, 190, 198)
  fill_rect(pg, W, H, 0, K_MAGIC_2199, 48, K_MAGIC_2202, 190, 190, 198)
  fill_rect(pg, W, H, W-49, K_MAGIC_2199, W-1, K_MAGIC_2202, 190, 190, 198)
  // salutation + wrapped body + closing
  let sal: *u8 = sys_mmap(320)
  var so: i64 = 0
  so = cpy(sal, so, "Dear " as *u8); so = cpy(sal, so, a[2] as *u8); sal[so] = 44 as u8; sal[so+1] = 0 as u8
  draw_text(pg, W, H, tbl, sal, 300, K_MAGIC_1250, 4, 4, 34, 36, 46)
  draw_wrap(pg, W, H, tbl, a[7] as *u8, 300, K_MAGIC_1380, 4, K_MAGIC_1950, 34, 36, 46)
  draw_text(pg, W, H, tbl, "Warm regards," as *u8, 300, K_MAGIC_2500, 4, 4, 34, 36, 46)
  draw_text(pg, W, H, tbl, a[1] as *u8, 300, K_MAGIC_2590, 4, 4, 34, 36, 46)
  draw_text(pg, W, H, tbl, "Composed by Nishi Mail on your own hardware", 300, K_MAGIC_3140, 2, 2, 150, 150, 162)
  nx_png_write_rgb(a[0] as *u8, pg, W, H)
  p("NISHI-ENVELOPE letter=" as *u8); p(a[0] as *u8); p(" size=2550x3300 window-zone-addressed tri-fold\n" as *u8)
  return 0
216}
217// the No.10 envelope face: 9.5 x 4.125 in @300dpi = 2850x1238; window 4.5x1.125in at 0.875in left / 0.5in bottom
218// a: [0]=out.png [1]=sender [2]=sender-cityline [3]=recipient [4]=line1 [5]=cityline
219func compose_envelope(a: *i64) -> i64 {
  let W: i64 = K_MAGIC_2850
  let H: i64 = K_MAGIC_1238
  let tbl: *u8 = font8x8_table()
  let pg: *u8 = sys_mmap(W * H * 3)
  fill_rect(pg, W, H, 0, 0, W-1, H-1, 255, 255, 255)
  // return address top-left
  draw_text(pg, W, H, tbl, a[1] as *u8, 150, 120, 3, 3, 34, 36, 46)
  draw_text(pg, W, H, tbl, a[2] as *u8, 150, 190, 3, 3, 34, 36, 46)
  // stamp box top-right
  rect_outline(pg, W, H, K_MAGIC_2620, 90, K_MAGIC_2760, 240, 4, 150, 150, 162)
  draw_text(pg, W, H, tbl, "STAMP" as *u8, K_MAGIC_2640, 150, 2, 2, 150, 150, 162)
  // the window: x 0.875in=262, w 4.5in=1350; 1.125in=337 tall, 0.5in=150 from bottom
  rect_outline(pg, W, H, 262, 751, K_MAGIC_1612, K_MAGIC_1088, 3, 210, 210, 216)
  draw_text(pg, W, H, tbl, a[3] as *u8, 330, 800, 4, 4, 34, 36, 46)
  draw_text(pg, W, H, tbl, a[4] as *u8, 330, 870, 4, 4, 34, 36, 46)
  draw_text(pg, W, H, tbl, a[5] as *u8, 330, 940, 4, 4, 34, 36, 46)
  nx_png_write_rgb(a[0] as *u8, pg, W, H)
  p("NISHI-ENVELOPE face=" as *u8); p(a[0] as *u8); p(" size=2850x1238 (No.10, window at spec)\n" as *u8)
  return 0
239}
240// ===== NISHI-FOLDCARD: A7 folded card (5.25 x 7.25 in panels) = two duplex sheets 3150x2175 =====
241// a: [0]=outside.png [1]=inside.png [2]=greeting [3]=message [4]=recipient [5]=sender
242func compose_card(a: *i64) -> i64 {
  let W: i64 = K_MAGIC_3150
  let H: i64 = K_MAGIC_2175
  let PW: i64 = K_MAGIC_1575
  let tbl: *u8 = font8x8_table()
  // OUTSIDE sheet: left = back cover, right = front cover
  let os: *u8 = sys_mmap(W * H * 3)
  fill_rect(os, W, H, 0, 0, W-1, H-1, 250, 247, 240)
  fill_rect(os, W, H, PW, 0, W-1, H-1, 34, 110, 140)
  fill_rect(os, W, H, PW+70, 70, W-71, H-71, 250, 247, 240)
  rect_outline(os, W, H, PW+96, 96, W-97, H-97, 5, 190, 60, 70)
  let gsc: i64 = 7
  let gx: i64 = PW + (PW - text_w(a[2] as *u8, gsc, gsc)) / 2
  draw_text(os, W, H, tbl, a[2] as *u8, gx, 900, gsc, gsc, 34, 36, 46)
  let sub: *u8 = "with love, via Nishi Mail"
  draw_text(os, W, H, tbl, sub, PW + (PW - text_w(sub, 3, 3)) / 2, K_MAGIC_1250, 3, 3, 190, 60, 70)
  let bk: *u8 = "Nishi Mail - on your own hardware"
  draw_text(os, W, H, tbl, bk, (PW - text_w(bk, 2, 2)) / 2, K_MAGIC_2050, 2, 2, 150, 150, 162)
  fill_rect(os, W, H, PW-1, 0, PW+1, 40, 190, 190, 198)
  fill_rect(os, W, H, PW-1, H-41, PW+1, H-1, 190, 190, 198)
  nx_png_write_rgb(a[0] as *u8, os, W, H)
  // INSIDE sheet: left blank, right = message
  let ins: *u8 = sys_mmap(W * H * 3)
  fill_rect(ins, W, H, 0, 0, W-1, H-1, 250, 247, 240)
  let sal: *u8 = sys_mmap(320)
  var so: i64 = 0
  so = cpy(sal, so, "Dear " as *u8); so = cpy(sal, so, a[4] as *u8); sal[so] = 44 as u8; sal[so+1] = 0 as u8
  draw_text(ins, W, H, tbl, sal, PW + 130, 300, 4, 4, 34, 36, 46)
  draw_wrap(ins, W, H, tbl, a[3] as *u8, PW + 130, 430, 4, K_MAGIC_1300, 34, 36, 46)
  draw_text(ins, W, H, tbl, "With love," as *u8, PW + 130, K_MAGIC_1800, 4, 4, 34, 36, 46)
  draw_text(ins, W, H, tbl, a[5] as *u8, PW + 130, K_MAGIC_1890, 4, 4, 34, 36, 46)
  nx_png_write_rgb(a[1] as *u8, ins, W, H)
  p("NISHI-FOLDCARD outside=" as *u8); p(a[0] as *u8); p(" inside=" as *u8); p(a[1] as *u8); p(" size=3150x2175 (A7 duplex, fold-ticked)\n" as *u8)
  return 0
276}
277
278func cmd_selftest() -> i64 {
  p("=== NX-MAILPIECE SELFTEST (NISHI-POSTCARD compose -> PNG) ===\n" as *u8)
  let fp: *u8 = "knowledge/fetched/nishi_postcard_front.png\x00" as *u8
  let bp: *u8 = "knowledge/fetched/nishi_postcard_back.png\x00" as *u8
  let msg: *u8 = "Thinking of you on your special day. Wish we could be there to celebrate. Sending love and a little sunshine from far away, on paper you can hold." as *u8
  compose(fp, bp, "HAPPY BIRTHDAY" as *u8, msg, "Grandma Rose" as *u8, "742 Evergreen Terrace" as *u8, "Springfield" as *u8, "IL" as *u8, "62704" as *u8)
  let fs: i64 = fsize(fp)
  let bs: i64 = fsize(bp)
  var ok: i64 = 1
  if fs < 100 { ok = 0 }
  if bs < 100 { ok = 0 }
289
  // R3: letter (window-zone address + tri-fold) + No.10 envelope face + A7 folded card
  let la: *i64 = sys_mmap(8 * 10) as *i64
  la[0] = "knowledge/fetched/nishi_letter.png" as *u8 as i64
  la[1] = "Jason West" as *u8 as i64
  la[2] = "Grandma Rose" as *u8 as i64
  la[3] = "742 Evergreen Terrace" as *u8 as i64
  la[4] = "Springfield" as *u8 as i64
  la[5] = "IL" as *u8 as i64
  la[6] = "62704" as *u8 as i64
  la[7] = "Just a note to say we are thinking of you. The garden is in full bloom and the kids ask about you every day. We will visit soon and bring photographs of everything you have missed." as *u8 as i64
  compose_letter(la)
  let ea: *i64 = sys_mmap(8 * 8) as *i64
  ea[0] = "knowledge/fetched/nishi_envelope.png" as *u8 as i64
  ea[1] = "Jason West" as *u8 as i64
  ea[2] = "Springfield, IL 62704" as *u8 as i64
  ea[3] = "Grandma Rose" as *u8 as i64
  ea[4] = "742 Evergreen Terrace" as *u8 as i64
  ea[5] = "Springfield, IL 62704" as *u8 as i64
  compose_envelope(ea)
  let ca: *i64 = sys_mmap(8 * 8) as *i64
  ca[0] = "knowledge/fetched/nishi_card_outside.png" as *u8 as i64
  ca[1] = "knowledge/fetched/nishi_card_inside.png" as *u8 as i64
  ca[2] = "HAPPY BIRTHDAY" as *u8 as i64
  ca[3] = "Eighty years young and still the heart of this family. We cannot wait to celebrate with you." as *u8 as i64
  ca[4] = "Grandma Rose" as *u8 as i64
  ca[5] = "Jason and the kids" as *u8 as i64
  compose_card(ca)
  let ls: i64 = fsize(la[0] as *u8)
  let es: i64 = fsize(ea[0] as *u8)
  let cos: i64 = fsize(ca[0] as *u8)
  let cis: i64 = fsize(ca[1] as *u8)
  if ls < 100 { ok = 0 }
  if es < 100 { ok = 0 }
  if cos < 100 { ok = 0 }
  if cis < 100 { ok = 0 }
325
  p("NISHI-MAILPIECE-SELFTEST postcard=" as *u8); pn(fs); p("/" as *u8); pn(bs)
  p(" letter=" as *u8); pn(ls); p(" envelope=" as *u8); pn(es)
  p(" card=" as *u8); pn(cos); p("/" as *u8); pn(cis)
  if ok == 1 { p(" verdict=GREEN\n" as *u8); return 0 }
  p(" verdict=RED\n" as *u8)
  return 1
332}
333
334func main(argc: i64, argv: *i64) -> i64 {
  if argc < 2 { return cmd_selftest() }
  let cmd: *u8 = argv[1] as *u8
  if seq(cmd, "selftest" as *u8) == 1 { return cmd_selftest() }
  if seq(cmd, "postcard" as *u8) == 1 {
      if argc < 11 { p("usage: postcard <front.png> <back.png> <greeting> <message> <recipient> <line1> <city> <region> <postal>\n" as *u8); return 1 }
      return compose(argv[2] as *u8, argv[3] as *u8, argv[4] as *u8, argv[5] as *u8, argv[6] as *u8, argv[7] as *u8, argv[8] as *u8, argv[9] as *u8, argv[10] as *u8)
  }
  if seq(cmd, "letter" as *u8) == 1 {
      if argc < 10 { p("usage: letter <out.png> <sender> <recipient> <line1> <city> <region> <postal> <body>\n" as *u8); return 1 }
      return compose_letter(((argv as i64) + 16) as *i64)
  }
  if seq(cmd, "envelope" as *u8) == 1 {
      if argc < 8 { p("usage: envelope <out.png> <sender> <sendercity> <recipient> <line1> <cityline>\n" as *u8); return 1 }
      return compose_envelope(((argv as i64) + 16) as *i64)
  }
  if seq(cmd, "card" as *u8) == 1 {
      if argc < 8 { p("usage: card <outside.png> <inside.png> <greeting> <message> <recipient> <sender>\n" as *u8); return 1 }
      return compose_card(((argv as i64) + 16) as *i64)
  }
  p("NX-MAILPIECE usage: postcard | letter | envelope | card | selftest\n" as *u8)
  return 1
356}
nx_mailpiece.nx source

`nx_mailpiece.nx` source
