feat: tty and ttf, you'd think somethn starting with tt would be fun to do...

1 files changed, 151 insertions, 0 deletions

diff --git a/kernel/tty.rv b/kernel/tty.rv
new file mode 100644
index 0000000..5fcd224
--- /dev/null
+++ b/kernel/tty.rv
@@ -0,0 +1,151 @@
+# tty layer as opposed to a future window management server bullshit thingy
+# this is just tty0 it adds nice shit like ^B and stuff
+# also has history and shit
+
+global tty = {
+  line = "", cursor = 0, esc = 0,
+  history = {}, hist_index = 0,
+
+  back = fn(self, n) do
+    let i = 0
+    while i < n do puts("\x08") i += 1 end
+  end,
+  blanks = fn(self, n) do
+    let i = 0
+    while i < n do puts(" ") i += 1 end
+  end,
+
+  insert = fn(self, ch) do
+    const pre = self.line[0..self.cursor]
+    const post = self.line[self.cursor..]
+    self.line = pre ~ ch ~ post
+    puts(ch ~ post)
+    self:back(post:len())
+    self.cursor += 1
+  end,
+
+  backspace = fn(self) do
+    if self.cursor == 0 return :nil
+    const pre = self.line[0..(self.cursor - 1)]
+    const post = self.line[self.cursor..]
+    self.line = pre ~ post
+    self.cursor -= 1
+    puts("\x08")
+    puts(post ~ " ")
+    self:back(post:len() + 1)
+  end,
+
+  move_left = fn(self) do
+    if self.cursor > 0 do puts("\x08") self.cursor -= 1 end
+  end,
+  move_right = fn(self) do
+    if self.cursor < self.line:len() do puts(self.line[self.cursor]) self.cursor += 1 end
+  end,
+  home = fn(self) do
+    self:back(self.cursor)
+    self.cursor = 0
+  end,
+  to_end = fn(self) do
+    puts(self.line[self.cursor..])
+    self.cursor = self.line:len()
+  end,
+
+  kill = fn(self) do
+    self:back(self.cursor)
+    self:blanks(self.line:len())
+    self:back(self.line:len())
+    self.line = ""
+    self.cursor = 0
+  end,
+
+  erase_word = fn(self) do
+    if self.cursor == 0 return :nil
+    let at = self.cursor
+    while (at > 0 and self.line[at - 1] == " ") do at -= 1 end
+    while (at > 0 and self.line[at - 1] != " ") do at -= 1 end
+    let count = self.cursor - at
+    while count > 0 do self:backspace() count -= 1 end
+  end,
+
+  replace_line = fn(self, text) do
+    self:kill()
+    self.line = text
+    puts(text)
+    self.cursor = text:len()
+  end,
+
+  history_prev = fn(self) do
+    if self.history:len() == 0 return :nil
+    if self.hist_index > 0 do self.hist_index -= 1 end
+    self:replace_line(self.history[self.hist_index])
+  end,
+  history_next = fn(self) do
+    if self.history:len() == 0 return :nil
+    if self.hist_index < self.history:len() - 1 do
+      self.hist_index += 1
+      self:replace_line(self.history[self.hist_index])
+    end
+    else do
+      self.hist_index = self.history:len()
+      self:replace_line("")
+    end
+  end,
+
+  submit = fn(self) do
+    puts("\n")
+    const entered = self.line
+    if entered:len() > 0 do self.history:push(entered) end
+    self.hist_index = self.history:len()
+    self.line = ""
+    self.cursor = 0
+    run(entered)
+  end,
+
+  cancel = fn(self) do
+    puts("^C\n")
+    self.line = ""
+    self.cursor = 0
+    self.hist_index = self.history:len()
+    puts(prompt())
+  end,
+
+  clear_screen = fn(self) do
+    console:clear()
+    puts(prompt())
+    puts(self.line)
+    self:back(self.line:len() - self.cursor)
+  end,
+
+  feed = fn(self, byte) do
+    if stdin_deliver(byte) return :nil
+
+    if self.esc == 1 do
+      if byte == 91 do self.esc = 2 end
+      else do self.esc = 0 end
+      return :nil
+    end
+    if self.esc == 2 do
+      self.esc = 0
+      if byte == 65 do self:history_prev() end       # up
+      else if byte == 66 do self:history_next() end  # down
+      else if byte == 67 do self:move_right() end    # right
+      else if byte == 68 do self:move_left() end     # left
+      else if byte == 72 do self:home() end          # home
+      else if byte == 70 do self:to_end() end        # end
+      return :nil
+    end
+    if byte == 27 do self.esc = 1 return :nil end    # ESC, start a sequence
+
+    if byte == 10 do self:submit() return :nil end       # enter
+    if byte == 8 or byte == 127 do self:backspace() return :nil end # bs / del
+    if byte == 1 do self:home() return :nil end          # ctrl-a
+    if byte == 5 do self:to_end() return :nil end        # ctrl-e
+    if byte == 3 do self:cancel() return :nil end        # ctrl-c
+    if byte == 12 do self:clear_screen() return :nil end # ctrl-l
+    if byte == 21 do self:kill() return :nil end         # ctrl-u
+    if byte == 23 do self:erase_word() return :nil end   # ctrl-w
+    if byte < 32 return :nil                             # ctrl-d and other ctrls: ignore
+    if byte > 126 return :nil
+    self:insert(string.of_ascii(byte))
+  end,
+}