From c9511f99db4bfd58ea361ae8422e2c3a335653ab Mon Sep 17 00:00:00 2001
From: Emery Hemingway <ehmry@posteo.net>
Date: Tue, 28 Dec 2021 12:38:40 +0100
Subject: [PATCH] Move xhtml rendering here

---
 src/private/render/xhtml.nim | 101 +++++++++++++++++++++++++++++++++++
 src/zua.nim                  |   4 +-
 2 files changed, 103 insertions(+), 2 deletions(-)
 create mode 100644 src/private/render/xhtml.nim

diff --git a/src/private/render/xhtml.nim b/src/private/render/xhtml.nim
new file mode 100644
index 0000000..dbaf6dc
--- /dev/null
+++ b/src/private/render/xhtml.nim
@@ -0,0 +1,101 @@
+# SPDX-FileCopyrightText: ☭ 2021 Emery Hemingway
+# SPDX-License-Identifier: Unlicense
+
+import std/sequtils
+import pixie, pixie/systemtypefaces
+import svui
+
+type Typesetting* = object
+  h1, h2, h3, p: Font
+
+proc newFont(typeface: Typeface, size: float32): Font =
+  result = newFont(typeface)
+  result.size = size
+
+proc initTypesetting*(): Typesetting =
+  let typeface = readTypeface findSystemTypeface(family = "Gentium Plus")
+  result.h1 = newFont(typeface, 24)
+  result.h2 = newFont(typeface, 20)
+  result.h3 = newFont(typeface, 16)
+  result.p = newFont(typeface, 12)
+
+proc body(xhtml: Xhtml): XmlElement =
+  for e in xhtml.elements:
+    if e.orKind == XmlNodeKind.`XmlElement` and e.xmlElement.name == "body":
+      return e.xmlElement
+  raise newException(ValueError, "no body in XHTML document")
+
+proc name(node: XmlNode): string = node.xmlElement.name
+
+proc text(node: XmlNode): string =
+  case node.orKind
+  of XmlNodeKind.XmlElement:
+    for e in node.xmlElement.elements:
+      result.add e.text
+  of XmlNodeKind.XmlText:
+    result.add node.xmlText.data
+
+func height(arr: Arrangement): float =
+  if arr.positions.len > 0: result = arr.positions[arr.positions.high].y
+
+proc add(result: var Arrangement; other: sink Arrangement) =
+  if result.lines.len == 0:
+    result = other
+  else:
+    let runeOff = result.runes.len
+    add(result.lines, map(other.lines,
+      proc (x: (int, int)): (int, int) = (x[0]+runeOff, x[1]+runeOff)))
+    add(result.spans, map(other.spans,
+      proc (x: (int, int)): (int, int) = (x[0]+runeOff, x[1]+runeOff)))
+    add(result.fonts, other.fonts)
+    add(result.runes, other.runes)
+    let yOff = result.positions[result.positions.high].y
+    add(result.positions,
+      map(other.positions,
+        proc(pos: Vec2): Vec2 = vec2(pos.x, pos.y + yOff)))
+    add(result.selectionRects,
+      map(other.selectionRects,
+        proc(rect: Rect): Rect = rect(rect.x, rect.y + yOff, rect.w, rect.h)))
+
+proc render*(ts: Typesetting; xhtml: Xhtml): Image =
+  # TODO: render by font size, not by wh
+  var wh = computeBounds(ts.p, "X")
+  wh.x = wh.x * 80
+  wh.y = wh.y * 50
+  let margin = wh / 9.0
+  var
+    printSpace = wh * (7.0 / 9.0)
+    pages = @[Arrangement()]
+
+  proc pageEnd(): float =
+    let
+      pi = pages.high
+      li = pages[pi].lines.high
+      ci = pages[pi].lines[li][1]
+    pages[pi].positions[ci].y
+
+  proc append(span: Span) =
+    var arr = typeset(@[span], printSpace)
+    if pages[pages.high].height + arr.height < printSpace.y:
+      pages[pages.high].add arr
+    else:
+      discard
+
+  for e in xhtml.body.elements:
+    let tag = e.name
+    case tag
+    of "h1":
+      append newSpan(e.text & "\n", ts.h1)
+    of "h2":
+      append newSpan("\n" & e.text & "\n", ts.h2)
+    of "h3":
+      append newSpan("\n" & e.text & "\n", ts.h3)
+    of "p":
+      append newSpan("        " & e.text & "\n\n", ts.p)
+    else:
+      discard
+      # raise newException(ValueError, "unhandled element in XHTML :" & tag)
+
+  result = newImage(int wh.x, int wh.y)
+  fill(result, rgba(255, 255, 255, 255))
+  fillText(result, pages[0], translate(margin))
diff --git a/src/zua.nim b/src/zua.nim
index d0399e5..8875a1d 100644
--- a/src/zua.nim
+++ b/src/zua.nim
@@ -11,8 +11,8 @@ import nimsvg
 import bumpy, pixie, pixie/fileformats/svg
 
 import sdl2
-
-import svui, svui/render/xhtml
+import svui
+import ./private/render/xhtml
 
 type
   Svui = svui.Svui[Ref]