Add RowBox structure

1 files changed, 121 insertions, 0 deletions

diff --git a/src/layout/layout.nim b/src/layout/layout.nim
new file mode 100644
index 00000000..043c0e08
--- /dev/null
+++ b/src/layout/layout.nim
@@ -0,0 +1,121 @@
+import unicode
+
+import types/enums
+import html/dom
+import css/box
+import css/style
+import io/buffer
+import io/cell
+import utils/twtstr
+
+proc generateGrids(text: Text, maxwidth: int, maxheight: int, x: int, y: int, fromx: int = x): seq[CSSRowBox] =
+  var r: Rune
+  var rowbox: CSSRowBox
+  var i = 0
+  var whitespace = false
+  if fromx > x:
+    let m = fromx - x + maxwidth
+    var w = 0
+    while i < text.data.len:
+      let pi = i
+      fastRuneAt(text.data, i, r)
+      let rw = r.width()
+      if rw + w > m:
+        i = pi
+        break
+      else:
+        if r.isWhitespace():
+          if not whitespace:
+            whitespace = true
+            rowbox.runes.add(Rune(' '))
+            inc rowbox.width
+            w += rw
+        else:
+          if whitespace:
+            whitespace = false
+          rowbox.runes.add(r)
+          inc rowbox.width
+          w += rw
+
+    result.add(rowbox)
+
+  if i < text.data.len:
+    rowbox = CSSRowBox()
+    var w = 0
+    while i < text.data.len:
+      let pi = i
+      fastRuneAt(text.data, i, r)
+      let rw = r.width()
+      if rw + w > maxwidth:
+        i = pi
+        w = 0
+        result.add(rowbox)
+        rowbox = CSSRowBox()
+      else:
+        rowbox.runes.add(r)
+        inc rowbox.width
+        w += rw
+
+  if rowbox.width > 0:
+    result.add(rowbox)
+
+proc generateBox(text: Text, maxwidth: int, maxheight: int, x: int, y: int, fromx: int): CSSInlineBox =
+  new(result)
+  result.content = text.generateGrids(maxwidth, maxheight, x, y, fromx)
+  result.fromx = fromx
+  result.innerEdge.x1 = x
+  result.innerEdge.y1 = y
+  var height = 0
+  var width = 0
+  for grid in result.content:
+    inc height
+    width = max(width, grid.width)
+  
+  height = min(height, maxheight)
+  width = min(width, maxwidth)
+  result.innerEdge.x2 = x + width
+  result.innerEdge.y2 = y + height
+
+proc generateBox(elem: Element, maxwidth: int, maxheight: int, x: int = 0, y: int = 0, fromx: int = x): CSSBox
+
+proc generateChildBoxes(elem: Element, maxwidth: int, maxheight: int, x: int, y: int, fromx: int = 0): seq[CSSBox] =
+  var cx = fromx
+  var cy = y
+  for child in elem.childNodes:
+    case child.nodeType
+    of TEXT_NODE:
+      let box = Text(child).generateBox(maxwidth, maxheight, x, cy, cx)
+      if box != nil:
+        result.add(box)
+        cy += box.h
+        if box.content.len > 0:
+          cx = box.content[^1].width
+    of ELEMENT_NODE:
+      let box = Element(child).generateBox(maxwidth, maxheight, x, cy, cx)
+      if box != nil:
+        result.add(box)
+    else:
+      discard
+
+proc generateBox(elem: Element, maxwidth: int, maxheight: int, x: int = 0, y: int = 0, fromx: int = x): CSSBox =
+  if elem.cssvalues[RULE_DISPLAY].display == DISPLAY_NONE:
+    return nil
+
+  result = CSSBlockBox()
+  result.innerEdge.x1 = x
+  result.innerEdge.y1 = y
+
+  var width = 0
+  var height = 0
+  for box in elem.generateChildBoxes(maxwidth, maxheight, x, y, fromx):
+    result.children.add(box)
+    height += box.h
+    height = min(height, maxheight)
+    width = max(width, box.w)
+    width = min(width, maxwidth)
+
+  result.innerEdge.x2 = x + width
+  result.innerEdge.y2 = y + height
+
+proc alignBoxes*(buffer: Buffer) =
+  buffer.rootbox = buffer.document.root.generateBox(buffer.width, buffer.height)