1 files changed, 177 insertions, 0 deletions
diff --git a/src/html/formdata.nim b/src/html/formdata.nim
new file mode 100644
index 00000000..bbf9a843
--- /dev/null
+++ b/src/html/formdata.nim
@@ -0,0 +1,177 @@
+import std/base64
+import std/streams
+
+import html/catom
+import html/dom
+import html/enums
+import js/domexception
+import js/javascript
+import js/tojs
+import types/blob
+import types/formdata
+import utils/twtstr
+
+import chame/tags
+
+proc constructEntryList*(form: HTMLFormElement, submitter: Element = nil,
+    encoding = "UTF-8"): seq[FormDataEntry]
+
+proc generateBoundary(): string =
+  let urandom = newFileStream("/dev/urandom")
+  let s = urandom.readStr(32)
+  urandom.close()
+  # 32 * 4 / 3 (padded) = 44 + prefix string is 22 bytes = 66 bytes
+  return "----WebKitFormBoundary" & base64.encode(s)
+
+proc newFormData0*(): FormData =
+  return FormData(boundary: generateBoundary())
+
+proc newFormData*(form: HTMLFormElement = nil,
+    submitter: HTMLElement = nil): DOMResult[FormData] {.jsctor.} =
+  let this = newFormData0()
+  if form != nil:
+    if submitter != nil:
+      if not submitter.isSubmitButton():
+        return errDOMException("Submitter must be a submit button",
+          "InvalidStateError")
+      if FormAssociatedElement(submitter).form != form:
+        return errDOMException("Submitter's form owner is not form",
+          "InvalidStateError")
+    if not form.constructingEntryList:
+      this.entries = constructEntryList(form, submitter)
+  return ok(this)
+
+#TODO filename should not be allowed for string entries
+# in other words, this should be an overloaded function, not just an or type
+proc append*[T: string|Blob](this: FormData, name: string, value: T,
+    filename = opt(string)) {.jsfunc.} =
+  when T is Blob:
+    let filename = if filename.isSome:
+      filename.get
+    elif value of WebFile:
+      WebFile(value).name
+    else:
+      "blob"
+    this.entries.add(FormDataEntry(
+      name: name,
+      isstr: false,
+      value: value,
+      filename: filename
+    ))
+  else: # string
+    this.entries.add(FormDataEntry(
+      name: name,
+      isstr: true,
+      svalue: value
+    ))
+
+proc delete(this: FormData, name: string) {.jsfunc.} =
+  for i in countdown(this.entries.high, 0):
+    if this.entries[i].name == name:
+      this.entries.delete(i)
+
+proc get(ctx: JSContext, this: FormData, name: string): JSValue {.jsfunc.} =
+  for entry in this.entries:
+    if entry.name == name:
+      if entry.isstr:
+        return toJS(ctx, entry.svalue)
+      else:
+        return toJS(ctx, entry.value)
+  return JS_NULL
+
+proc getAll(ctx: JSContext, this: FormData, name: string): seq[JSValue]
+    {.jsfunc.} =
+  for entry in this.entries:
+    if entry.name == name:
+      if entry.isstr:
+        result.add(toJS(ctx, entry.svalue))
+      else:
+        result.add(toJS(ctx, entry.value))
+
+proc add(list: var seq[FormDataEntry], entry: tuple[name, value: string]) =
+  list.add(FormDataEntry(
+    name: entry.name,
+    isstr: true,
+    svalue: entry.value
+  ))
+
+func toNameValuePairs*(list: seq[FormDataEntry]):
+    seq[tuple[name, value: string]] =
+  for entry in list:
+    if entry.isstr:
+      result.add((entry.name, entry.svalue))
+    else:
+      result.add((entry.name, entry.name))
+
+# https://html.spec.whatwg.org/multipage/form-control-infrastructure.html#constructing-the-form-data-set
+# Warning: we skip the first "constructing entry list" check; the caller must
+# do it.
+proc constructEntryList*(form: HTMLFormElement, submitter: Element = nil,
+    encoding = "UTF-8"): seq[FormDataEntry] =
+  assert not form.constructingEntryList
+  form.constructingEntryList = true
+  var entrylist: seq[FormDataEntry] = @[]
+  for field in form.controls:
+    if field.findAncestor({TAG_DATALIST}) != nil or
+        field.attrb(atDisabled) or
+        field.isButton() and Element(field) != submitter:
+      continue
+    if field of HTMLInputElement:
+      let field = HTMLInputElement(field)
+      if field.inputType in {INPUT_CHECKBOX, INPUT_RADIO} and not field.checked:
+        continue
+      if field.inputType == INPUT_IMAGE:
+        var name = field.attr(atName)
+        if name != "":
+          name &= '.'
+        entrylist.add((name & 'x', $field.xcoord))
+        entrylist.add((name & 'y', $field.ycoord))
+        continue
+    #TODO custom elements
+    let name = field.attr(atName)
+    if name == "":
+      continue
+    if field of HTMLSelectElement:
+      let field = HTMLSelectElement(field)
+      for option in field.options:
+        if option.selected and not option.isDisabled:
+          entrylist.add((name, option.value))
+    elif field of HTMLInputElement:
+      let field = HTMLInputElement(field)
+      case field.inputType
+      of INPUT_CHECKBOX, INPUT_RADIO:
+        let v = field.attr(atValue)
+        let value = if v != "":
+          v
+        else:
+          "on"
+        entrylist.add((name, value))
+      of INPUT_FILE:
+        #TODO file
+        discard
+      of INPUT_HIDDEN:
+        if name.equalsIgnoreCase("_charset_"):
+          entrylist.add((name, encoding))
+        else:
+          entrylist.add((name, field.value))
+      else:
+        entrylist.add((name, field.value))
+    elif field of HTMLButtonElement:
+      entrylist.add((name, HTMLButtonElement(field).value))
+    elif field of HTMLTextAreaElement:
+      entrylist.add((name, HTMLTextAreaElement(field).value))
+    else:
+      assert false, "Tag type " & $field.tagType &
+        " not accounted for in constructEntryList"
+    if field of HTMLTextAreaElement or
+        field of HTMLInputElement and
+        HTMLInputElement(field).inputType in AutoDirInput:
+      let dirname = field.attr(atDirname)
+      if dirname != "":
+        let dir = "ltr" #TODO bidi
+        entrylist.add((dirname, dir))
+  form.constructingEntryList = false
+  return entrylist
+
+proc addFormDataModule*(ctx: JSContext) =
+  ctx.registerType(FormData)