From e5909cf432dfebf1676de3fc184f3e2f3ef4cf14 Mon Sep 17 00:00:00 2001
From: peterbessman <peter@peterbessman.com>
Date: Wed, 3 Feb 2021 13:31:05 -0500
Subject: [PATCH] Create node.lua

Refactored Node out of rootview.lua
---
 data/core/node.lua | 375 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 375 insertions(+)
 create mode 100644 data/core/node.lua

diff --git a/data/core/node.lua b/data/core/node.lua
new file mode 100644
index 0000000..43b0d8c
--- /dev/null
+++ b/data/core/node.lua
@@ -0,0 +1,375 @@
+local core = require "core"
+local common = require "core.common"
+local style = require "core.style"
+local keymap = require "core.keymap"
+local Object = require "core.object"
+local View = require "core.view"
+-- local DocView = require "core.docview"
+
+local EmptyView = View:extend()
+
+local function draw_text(x, y, color)
+  local th = style.big_font:get_height()
+  local dh = th + style.padding.y * 2
+  x = renderer.draw_text(style.big_font, "lite", x, y + (dh - th) / 2, color)
+  x = x + style.padding.x
+  renderer.draw_rect(x, y, math.ceil(1 * SCALE), dh, color)
+  local lines = {
+    { fmt = "%s to run a command", cmd = "core:find-command" },
+    { fmt = "%s to open a file from the project", cmd = "core:find-file" },
+  }
+  th = style.font:get_height()
+  y = y + (dh - th * 2 - style.padding.y) / 2
+  local w = 0
+  for _, line in ipairs(lines) do
+    local text = string.format(line.fmt, keymap.get_binding(line.cmd))
+    w = math.max(w, renderer.draw_text(style.font, text, x + style.padding.x, y, color))
+    y = y + th + style.padding.y
+  end
+  return w, dh
+end
+
+function EmptyView:draw()
+  self:draw_background(style.background)
+  local w, h = draw_text(0, 0, { 0, 0, 0, 0 })
+  local x = self.position.x + math.max(style.padding.x, (self.size.x - w) / 2)
+  local y = self.position.y + (self.size.y - h) / 2
+  draw_text(x, y, style.dim)
+end
+
+local Node = Object:extend()
+
+function Node:new(type)
+  self.type = type or "leaf"
+  self.position = { x = 0, y = 0 }
+  self.size = { x = 0, y = 0 }
+  self.views = {}
+  self.divider = 0.5
+  if self.type == "leaf" then
+    self:add_view(EmptyView())
+  end
+end
+
+
+function Node:propagate(fn, ...)
+  self.a[fn](self.a, ...)
+  self.b[fn](self.b, ...)
+end
+
+
+function Node:on_mouse_moved(x, y, ...)
+  self.hovered_tab = self:get_tab_overlapping_point(x, y)
+  if self.type == "leaf" then
+    self.active_view:on_mouse_moved(x, y, ...)
+  else
+    self:propagate("on_mouse_moved", x, y, ...)
+  end
+end
+
+
+function Node:on_mouse_released(...)
+  if self.type == "leaf" then
+    self.active_view:on_mouse_released(...)
+  else
+    self:propagate("on_mouse_released", ...)
+  end
+end
+
+
+function Node:consume(node)
+  for k, _ in pairs(self) do self[k] = nil end
+  for k, v in pairs(node) do self[k] = v   end
+end
+
+
+local type_map = { up="vsplit", down="vsplit", left="hsplit", right="hsplit" }
+
+function Node:split(dir, view, locked)
+  assert(self.type == "leaf", "Tried to split non-leaf node")
+  local type = assert(type_map[dir], "Invalid direction")
+  local last_active = core.active_view
+  local child = Node()
+  child:consume(self)
+  self:consume(Node(type))
+  self.a = child
+  self.b = Node()
+  if view then self.b:add_view(view) end
+  if locked then
+    self.b.locked = locked
+    core.set_active_view(last_active)
+  end
+  if dir == "up" or dir == "left" then
+    self.a, self.b = self.b, self.a
+  end
+  return child
+end
+
+
+function Node:close_active_view(root)
+  local do_close = function()
+    if #self.views > 1 then
+      local idx = self:get_view_idx(self.active_view)
+      table.remove(self.views, idx)
+      self:set_active_view(self.views[idx] or self.views[#self.views])
+    else
+      local parent = self:get_parent_node(root)
+      local is_a = (parent.a == self)
+      local other = parent[is_a and "b" or "a"]
+      if other:get_locked_size() then
+        self.views = {}
+        self:add_view(EmptyView())
+      else
+        parent:consume(other)
+        local p = parent
+        while p.type ~= "leaf" do
+          p = p[is_a and "a" or "b"]
+        end
+        p:set_active_view(p.active_view)
+      end
+    end
+    core.last_active_view = nil
+  end
+  self.active_view:try_close(do_close)
+end
+
+
+function Node:add_view(view)
+  assert(self.type == "leaf", "Tried to add view to non-leaf node")
+  assert(not self.locked, "Tried to add view to locked node")
+  if self.views[1] and self.views[1]:is(EmptyView) then
+    table.remove(self.views)
+  end
+  table.insert(self.views, view)
+  self:set_active_view(view)
+end
+
+
+function Node:set_active_view(view)
+  assert(self.type == "leaf", "Tried to set active view on non-leaf node")
+  self.active_view = view
+  core.set_active_view(view)
+end
+
+
+function Node:get_view_idx(view)
+  for i, v in ipairs(self.views) do
+    if v == view then return i end
+  end
+end
+
+
+function Node:get_node_for_view(view)
+  for _, v in ipairs(self.views) do
+    if v == view then return self end
+  end
+  if self.type ~= "leaf" then
+    return self.a:get_node_for_view(view) or self.b:get_node_for_view(view)
+  end
+end
+
+
+function Node:get_parent_node(root)
+  if root.a == self or root.b == self then
+    return root
+  elseif root.type ~= "leaf" then
+    return self:get_parent_node(root.a) or self:get_parent_node(root.b)
+  end
+end
+
+
+function Node:get_children(t)
+  t = t or {}
+  for _, view in ipairs(self.views) do
+    table.insert(t, view)
+  end
+  if self.a then self.a:get_children(t) end
+  if self.b then self.b:get_children(t) end
+  return t
+end
+
+
+function Node:get_divider_overlapping_point(px, py)
+  if self.type ~= "leaf" then
+    local p = 6
+    local x, y, w, h = self:get_divider_rect()
+    x, y = x - p, y - p
+    w, h = w + p * 2, h + p * 2
+    if px > x and py > y and px < x + w and py < y + h then
+      return self
+    end
+    return self.a:get_divider_overlapping_point(px, py)
+        or self.b:get_divider_overlapping_point(px, py)
+  end
+end
+
+
+function Node:get_tab_overlapping_point(px, py)
+  if #self.views == 1 then return nil end
+  local x, y, w, h = self:get_tab_rect(1)
+  if px >= x and py >= y and px < x + w * #self.views and py < y + h then
+    return math.floor((px - x) / w) + 1
+  end
+end
+
+
+function Node:get_child_overlapping_point(x, y)
+  local child
+  if self.type == "leaf" then
+    return self
+  elseif self.type == "hsplit" then
+    child = (x < self.b.position.x) and self.a or self.b
+  elseif self.type == "vsplit" then
+    child = (y < self.b.position.y) and self.a or self.b
+  end
+  return child:get_child_overlapping_point(x, y)
+end
+
+
+function Node:get_tab_rect(idx)
+  local tw = math.min(style.tab_width, math.ceil(self.size.x / #self.views))
+  local h = style.font:get_height() + style.padding.y * 2
+  return self.position.x + (idx-1) * tw, self.position.y, tw, h
+end
+
+
+function Node:get_divider_rect()
+  local x, y = self.position.x, self.position.y
+  if self.type == "hsplit" then
+    return x + self.a.size.x, y, style.divider_size, self.size.y
+  elseif self.type == "vsplit" then
+    return x, y + self.a.size.y, self.size.x, style.divider_size
+  end
+end
+
+
+function Node:get_locked_size()
+  if self.type == "leaf" then
+    if self.locked then
+      local size = self.active_view.size
+      return size.x, size.y
+    end
+  else
+    local x1, y1 = self.a:get_locked_size()
+    local x2, y2 = self.b:get_locked_size()
+    if x1 and x2 then
+      local dsx = (x1 < 1 or x2 < 1) and 0 or style.divider_size
+      local dsy = (y1 < 1 or y2 < 1) and 0 or style.divider_size
+      return x1 + x2 + dsx, y1 + y2 + dsy
+    end
+  end
+end
+
+
+local function copy_position_and_size(dst, src)
+  dst.position.x, dst.position.y = src.position.x, src.position.y
+  dst.size.x, dst.size.y = src.size.x, src.size.y
+end
+
+
+-- calculating the sizes is the same for hsplits and vsplits, except the x/y
+-- axis are swapped; this function lets us use the same code for both
+local function calc_split_sizes(self, x, y, x1, x2)
+  local n
+  local ds = (x1 and x1 < 1 or x2 and x2 < 1) and 0 or style.divider_size
+  if x1 then
+    n = x1 + ds
+  elseif x2 then
+    n = self.size[x] - x2
+  else
+    n = math.floor(self.size[x] * self.divider)
+  end
+  self.a.position[x] = self.position[x]
+  self.a.position[y] = self.position[y]
+  self.a.size[x] = n - ds
+  self.a.size[y] = self.size[y]
+  self.b.position[x] = self.position[x] + n
+  self.b.position[y] = self.position[y]
+  self.b.size[x] = self.size[x] - n
+  self.b.size[y] = self.size[y]
+end
+
+
+function Node:update_layout()
+  if self.type == "leaf" then
+    local av = self.active_view
+    if #self.views > 1 then
+      local _, _, _, th = self:get_tab_rect(1)
+      av.position.x, av.position.y = self.position.x, self.position.y + th
+      av.size.x, av.size.y = self.size.x, self.size.y - th
+    else
+      copy_position_and_size(av, self)
+    end
+  else
+    local x1, y1 = self.a:get_locked_size()
+    local x2, y2 = self.b:get_locked_size()
+    if self.type == "hsplit" then
+      calc_split_sizes(self, "x", "y", x1, x2)
+    elseif self.type == "vsplit" then
+      calc_split_sizes(self, "y", "x", y1, y2)
+    end
+    self.a:update_layout()
+    self.b:update_layout()
+  end
+end
+
+
+function Node:update()
+  if self.type == "leaf" then
+    for _, view in ipairs(self.views) do
+      view:update()
+    end
+  else
+    self.a:update()
+    self.b:update()
+  end
+end
+
+
+function Node:draw_tabs()
+  local x, y, _, h = self:get_tab_rect(1)
+  local ds = style.divider_size
+  core.push_clip_rect(x, y, self.size.x, h)
+  renderer.draw_rect(x, y, self.size.x, h, style.background2)
+  renderer.draw_rect(x, y + h - ds, self.size.x, ds, style.divider)
+
+  for i, view in ipairs(self.views) do
+    local x, y, w, h = self:get_tab_rect(i)
+    local text = view:get_name()
+    local color = style.dim
+    if view == self.active_view then
+      color = style.text
+      renderer.draw_rect(x, y, w, h, style.background)
+      renderer.draw_rect(x + w, y, ds, h, style.divider)
+      renderer.draw_rect(x - ds, y, ds, h, style.divider)
+    end
+    if i == self.hovered_tab then
+      color = style.text
+    end
+    core.push_clip_rect(x, y, w, h)
+    x, w = x + style.padding.x, w - style.padding.x * 2
+    local align = style.font:get_width(text) > w and "left" or "center"
+    common.draw_text(style.font, color, text, align, x, y, w, h)
+    core.pop_clip_rect()
+  end
+
+  core.pop_clip_rect()
+end
+
+
+function Node:draw()
+  if self.type == "leaf" then
+    if #self.views > 1 then
+      self:draw_tabs()
+    end
+    local pos, size = self.active_view.position, self.active_view.size
+    core.push_clip_rect(pos.x, pos.y, size.x + pos.x % 1, size.y + pos.y % 1)
+    self.active_view:draw()
+    core.pop_clip_rect()
+  else
+    local x, y, w, h = self:get_divider_rect()
+    renderer.draw_rect(x, y, w, h, style.divider)
+    self:propagate("draw")
+  end
+end
+
+return Node