chatgptviewer.lua

--[[--
Displays some text in a scrollable view.

@usage
    local chatgptviewer = ChatGPTViewer:new{
        title = _("I can scroll!"),
        text = _("I'll need to be longer than this example to scroll."),
    }
    UIManager:show(chatgptviewer)
]]
local BD = require("ui/bidi")
local Blitbuffer = require("ffi/blitbuffer")
local ButtonTable = require("ui/widget/buttontable")
local CenterContainer = require("ui/widget/container/centercontainer")
local CheckButton = require("ui/widget/checkbutton")
local Device = require("device")
local Geom = require("ui/geometry")
local Font = require("ui/font")
local FrameContainer = require("ui/widget/container/framecontainer")
local GestureRange = require("ui/gesturerange")
local InputContainer = require("ui/widget/container/inputcontainer")
local InputDialog = require("ui/widget/inputdialog")
local MovableContainer = require("ui/widget/container/movablecontainer")
local Notification = require("ui/widget/notification")
local ScrollTextWidget = require("ui/widget/scrolltextwidget")
local Size = require("ui/size")
local TitleBar = require("ui/widget/titlebar")
local UIManager = require("ui/uimanager")
local VerticalGroup = require("ui/widget/verticalgroup")
local WidgetContainer = require("ui/widget/container/widgetcontainer")
local T = require("ffi/util").template
local util = require("util")
local _ = require("gettext")
local Screen = Device.screen

local ChatGPTViewer = InputContainer:extend {
  title = nil,
  text = nil,
  width = nil,
  height = nil,
  buttons_table = nil,
  -- See TextBoxWidget for details about these options
  -- We default to justified and auto_para_direction to adapt
  -- to any kind of text we are given (book descriptions,
  -- bookmarks' text, translation results...).
  -- When used to display more technical text (HTML, CSS,
  -- application logs...), it's best to reset them to false.
  alignment = "left",
  justified = true,
  lang = nil,
  para_direction_rtl = nil,
  auto_para_direction = true,
  alignment_strict = false,

  title_face = nil,               -- use default from TitleBar
  title_multilines = nil,         -- see TitleBar for details
  title_shrink_font_to_fit = nil, -- see TitleBar for details
  text_face = Font:getFace("x_smallinfofont"),
  fgcolor = Blitbuffer.COLOR_BLACK,
  text_padding = Size.padding.large,
  text_margin = Size.margin.small,
  button_padding = Size.padding.default,
  -- Bottom row with Close, Find buttons. Also added when no caller's buttons defined.
  add_default_buttons = nil,
  default_hold_callback = nil,   -- on each default button
  find_centered_lines_count = 5, -- line with find results to be not far from the center

  onAskQuestion = nil,
}

function ChatGPTViewer:init()
  -- calculate window dimension
  self.align = "center"
  self.region = Geom:new {
    x = 0, y = 0,
    w = Screen:getWidth(),
    h = Screen:getHeight(),
  }
  self.width = self.width or Screen:getWidth() - Screen:scaleBySize(30)
  self.height = self.height or Screen:getHeight() - Screen:scaleBySize(30)

  self._find_next = false
  self._find_next_button = false
  self._old_virtual_line_num = 1

  if Device:hasKeys() then
    self.key_events.Close = { { Device.input.group.Back } }
  end

  if Device:isTouchDevice() then
    local range = Geom:new {
      x = 0, y = 0,
      w = Screen:getWidth(),
      h = Screen:getHeight(),
    }
    self.ges_events = {
      TapClose = {
        GestureRange:new {
          ges = "tap",
          range = range,
        },
      },
      Swipe = {
        GestureRange:new {
          ges = "swipe",
          range = range,
        },
      },
      MultiSwipe = {
        GestureRange:new {
          ges = "multiswipe",
          range = range,
        },
      },
      -- Allow selection of one or more words (see textboxwidget.lua):
      HoldStartText = {
        GestureRange:new {
          ges = "hold",
          range = range,
        },
      },
      HoldPanText = {
        GestureRange:new {
          ges = "hold",
          range = range,
        },
      },
      HoldReleaseText = {
        GestureRange:new {
          ges = "hold_release",
          range = range,
        },
        -- callback function when HoldReleaseText is handled as args
        args = function(text, hold_duration, start_idx, end_idx, to_source_index_func)
          self:handleTextSelection(text, hold_duration, start_idx, end_idx, to_source_index_func)
        end
      },
      -- These will be forwarded to MovableContainer after some checks
      ForwardingTouch = { GestureRange:new { ges = "touch", range = range, }, },
      ForwardingPan = { GestureRange:new { ges = "pan", range = range, }, },
      ForwardingPanRelease = { GestureRange:new { ges = "pan_release", range = range, }, },
    }
  end

  local titlebar = TitleBar:new {
    width = self.width,
    align = "left",
    with_bottom_line = true,
    title = self.title,
    title_face = self.title_face,
    title_multilines = self.title_multilines,
    title_shrink_font_to_fit = self.title_shrink_font_to_fit,
    close_callback = function() self:onClose() end,
    show_parent = self,
  }

  -- Callback to enable/disable buttons, for at-top/at-bottom feedback
  local prev_at_top = false -- Buttons were created enabled
  local prev_at_bottom = false
  local function button_update(id, enable)
    local button = self.button_table:getButtonById(id)
    if button then
      if enable then
        button:enable()
      else
        button:disable()
      end
      button:refresh()
    end
  end
  self._buttons_scroll_callback = function(low, high)
    if prev_at_top and low > 0 then
      button_update("top", true)
      prev_at_top = false
    elseif not prev_at_top and low <= 0 then
      button_update("top", false)
      prev_at_top = true
    end
    if prev_at_bottom and high < 1 then
      button_update("bottom", true)
      prev_at_bottom = false
    elseif not prev_at_bottom and high >= 1 then
      button_update("bottom", false)
      prev_at_bottom = true
    end
  end

  -- buttons
  local default_buttons =
  {
    {
      text = _("Ask Another Question"),
      id = "ask_another_question",
      callback = function()
        self:askAnotherQuestion()
      end,
    },
    {
      text = "⇱",
      id = "top",
      callback = function()
        self.scroll_text_w:scrollToTop()
      end,
      hold_callback = self.default_hold_callback,
      allow_hold_when_disabled = true,
    },
    {
      text = "⇲",
      id = "bottom",
      callback = function()
        self.scroll_text_w:scrollToBottom()
      end,
      hold_callback = self.default_hold_callback,
      allow_hold_when_disabled = true,
    },
    {
      text = _("Close"),
      callback = function()
        self:onClose()
      end,
      hold_callback = self.default_hold_callback,
    },
  }
  local buttons = self.buttons_table or {}
  if self.add_default_buttons or not self.buttons_table then
    table.insert(buttons, default_buttons)
  end
  self.button_table = ButtonTable:new {
    width = self.width - 2 * self.button_padding,
    buttons = buttons,
    zero_sep = true,
    show_parent = self,
  }

  local textw_height = self.height - titlebar:getHeight() - self.button_table:getSize().h

  self.scroll_text_w = ScrollTextWidget:new {
    text = self.text,
    face = self.text_face,
    fgcolor = self.fgcolor,
    width = self.width - 2 * self.text_padding - 2 * self.text_margin,
    height = textw_height - 2 * self.text_padding - 2 * self.text_margin,
    dialog = self,
    alignment = self.alignment,
    justified = self.justified,
    lang = self.lang,
    para_direction_rtl = self.para_direction_rtl,
    auto_para_direction = self.auto_para_direction,
    alignment_strict = self.alignment_strict,
    scroll_callback = self._buttons_scroll_callback,
  }
  self.textw = FrameContainer:new {
    padding = self.text_padding,
    margin = self.text_margin,
    bordersize = 0,
    self.scroll_text_w
  }

  self.frame = FrameContainer:new {
    radius = Size.radius.window,
    padding = 0,
    margin = 0,
    background = Blitbuffer.COLOR_WHITE,
    VerticalGroup:new {
      titlebar,
      CenterContainer:new {
        dimen = Geom:new {
          w = self.width,
          h = self.textw:getSize().h,
        },
        self.textw,
      },
      CenterContainer:new {
        dimen = Geom:new {
          w = self.width,
          h = self.button_table:getSize().h,
        },
        self.button_table,
      }
    }
  }
  self.movable = MovableContainer:new {
    -- We'll handle these events ourselves, and call appropriate
    -- MovableContainer's methods when we didn't process the event
    ignore_events = {
      -- These have effects over the text widget, and may
      -- or may not be processed by it
      "swipe", "hold", "hold_release", "hold_pan",
      -- These do not have direct effect over the text widget,
      -- but may happen while selecting text: we need to check
      -- a few things before forwarding them
      "touch", "pan", "pan_release",
    },
    self.frame,
  }
  self[1] = WidgetContainer:new {
    align = self.align,
    dimen = self.region,
    self.movable,
  }
end

function ChatGPTViewer:askAnotherQuestion()
  local input_dialog
  input_dialog = InputDialog:new {
    title = _("Ask another question"),
    input = "",
    input_type = "text",
    description = _("Enter your question for ChatGPT."),
    buttons = {
      {
        {
          text = _("Cancel"),
          callback = function()
            UIManager:close(input_dialog)
          end,
        },
        {
          text = _("Ask"),
          is_enter_default = true,
          callback = function()
            local input_text = input_dialog:getInputText()
            if input_text and input_text ~= "" then
              self:onAskQuestion(input_text)
            end
            UIManager:close(input_dialog)
          end,
        },
      },
    },
  }
  UIManager:show(input_dialog)
  input_dialog:onShowKeyboard()
end

function ChatGPTViewer:onCloseWidget()
  UIManager:setDirty(nil, function()
    return "partial", self.frame.dimen
  end)
end

function ChatGPTViewer:onShow()
  UIManager:setDirty(self, function()
    return "partial", self.frame.dimen
  end)
  return true
end

function ChatGPTViewer:onTapClose(arg, ges_ev)
  if ges_ev.pos:notIntersectWith(self.frame.dimen) then
    self:onClose()
  end
  return true
end

function ChatGPTViewer:onMultiSwipe(arg, ges_ev)
  -- For consistency with other fullscreen widgets where swipe south can't be
  -- used to close and where we then allow any multiswipe to close, allow any
  -- multiswipe to close this widget too.
  self:onClose()
  return true
end

function ChatGPTViewer:onClose()
  UIManager:close(self)
  if self.close_callback then
    self.close_callback()
  end
  return true
end

function ChatGPTViewer:onSwipe(arg, ges)
  if ges.pos:intersectWith(self.textw.dimen) then
    local direction = BD.flipDirectionIfMirroredUILayout(ges.direction)
    if direction == "west" then
      self.scroll_text_w:scrollText(1)
      return true
    elseif direction == "east" then
      self.scroll_text_w:scrollText(-1)
      return true
    else
      -- trigger a full-screen HQ flashing refresh
      UIManager:setDirty(nil, "full")
      -- a long diagonal swipe may also be used for taking a screenshot,
      -- so let it propagate
      return false
    end
  end
  -- Let our MovableContainer handle swipe outside of text
  return self.movable:onMovableSwipe(arg, ges)
end

-- The following handlers are similar to the ones in DictQuickLookup:
-- we just forward to our MoveableContainer the events that our
-- TextBoxWidget has not handled with text selection.
function ChatGPTViewer:onHoldStartText(_, ges)
  -- Forward Hold events not processed by TextBoxWidget event handler
  -- to our MovableContainer
  return self.movable:onMovableHold(_, ges)
end

function ChatGPTViewer:onHoldPanText(_, ges)
  -- Forward Hold events not processed by TextBoxWidget event handler
  -- to our MovableContainer
  -- We only forward it if we did forward the Touch
  if self.movable._touch_pre_pan_was_inside then
    return self.movable:onMovableHoldPan(arg, ges)
  end
end

function ChatGPTViewer:onHoldReleaseText(_, ges)
  -- Forward Hold events not processed by TextBoxWidget event handler
  -- to our MovableContainer
  return self.movable:onMovableHoldRelease(_, ges)
end

-- These 3 event processors are just used to forward these events
-- to our MovableContainer, under certain conditions, to avoid
-- unwanted moves of the window while we are selecting text in
-- the definition widget.
function ChatGPTViewer:onForwardingTouch(arg, ges)
  -- This Touch may be used as the Hold we don't get (for example,
  -- when we start our Hold on the bottom buttons)
  if not ges.pos:intersectWith(self.textw.dimen) then
    return self.movable:onMovableTouch(arg, ges)
  else
    -- Ensure this is unset, so we can use it to not forward HoldPan
    self.movable._touch_pre_pan_was_inside = false
  end
end

function ChatGPTViewer:onForwardingPan(arg, ges)
  -- We only forward it if we did forward the Touch or are currently moving
  if self.movable._touch_pre_pan_was_inside or self.movable._moving then
    return self.movable:onMovablePan(arg, ges)
  end
end

function ChatGPTViewer:onForwardingPanRelease(arg, ges)
  -- We can forward onMovablePanRelease() does enough checks
  return self.movable:onMovablePanRelease(arg, ges)
end

function ChatGPTViewer:handleTextSelection(text, hold_duration, start_idx, end_idx, to_source_index_func)
  if self.text_selection_callback then
    self.text_selection_callback(text, hold_duration, start_idx, end_idx, to_source_index_func)
    return
  end
  if Device:hasClipboard() then
    Device.input.setClipboardText(text)
    UIManager:show(Notification:new {
      text = start_idx == end_idx and _("Word copied to clipboard.")
          or _("Selection copied to clipboard."),
    })
  end
end

function ChatGPTViewer:update(new_text)
  UIManager:close(self)
  local updated_viewer = ChatGPTViewer:new {
    title = self.title,
    text = new_text,
    width = self.width,
    height = self.height,
    buttons_table = self.buttons_table,
    onAskQuestion = self.onAskQuestion,
  }
  updated_viewer.scroll_text_w:scrollToBottom()
  UIManager:show(updated_viewer)
end

return ChatGPTViewer