package.path = "./lua/lib/?.lua;" .. package.path

local files = {}
local cleared, invalidated = nil, {}

fs = {
  readFile = function(path, maxBytes)
    local value = files[path]
    if value and #value > maxBytes then return nil, "too large" end
    return value, value and nil or "missing"
  end,
  writeFile = function(path, value)
    files[path] = value
    return true
  end,
}

gui = {
  FONT_SMALL = 0,
  FONT_UI = 1,
  FONT_BODY = 2,
  FONT_LARGE = 3,
  STYLE_NORMAL = 0,
  STYLE_BOLD = 1,
  color = function(r, g, b) return r * 65536 + g * 256 + b end,
  getWidth = function() return 320 end,
  getHeight = function() return 480 end,
  getTextWidth = function(_, text) return #text * 6 end,
  getFontHeight = function() return 8 end,
  clear = function(color) cleared = color end,
}

local nodes, focus, painter = {}, nil, nil
local buttonCount = 0

local function interactiveNodes()
  local result = {}
  for id, entry in ipairs(nodes) do
    if entry.interactive then result[#result + 1] = id end
  end
  return result
end

node = {
  reset = function()
    nodes, focus, buttonCount = {}, nil, 0
  end,
  create = function(parent, spec)
    local id = #nodes + 1
    local x = 0
    if spec.type == "button" then
      buttonCount = buttonCount + 1
      x = (buttonCount - 1) * 100
    end
    nodes[id] = {
      parent = parent,
      type = spec.type,
      label = spec.label,
      interactive = spec.interactive,
      rect = {x, 0, 90, 50},
      pressed = false,
      style = {},
    }
    return id
  end,
  attach = function(parent, child) nodes[child].parent = parent end,
  setSize = function() end,
  setStyle = function(id, style)
    for key, value in pairs(style) do nodes[id].style[key] = value end
  end,
  layout = function() return true end,
  dropScratch = function() end,
  hit = function(_, x, y)
    for _, id in ipairs(interactiveNodes()) do
      local rect = nodes[id].rect
      if x >= rect[1] and x < rect[1] + rect[3] and y >= rect[2] and y < rect[2] + rect[4] then
        return id
      end
    end
  end,
  getRect = function(id) return table.unpack(nodes[id].rect) end,
  setLabel = function(id, text) nodes[id].label = text end,
  getLabel = function(id) return nodes[id].label end,
  invalidate = function(id) invalidated[#invalidated + 1] = id end,
  setPressed = function(id, pressed) nodes[id].pressed = pressed end,
  isPressed = function(id) return nodes[id].pressed end,
  setPainter = function(callback) painter = callback end,
  draw = function()
    if painter then
      for id, entry in ipairs(nodes) do
        if entry.type == "custom" then painter(id, table.unpack(entry.rect)) end
      end
    end
  end,
  focusFirst = function()
    focus = interactiveNodes()[1]
    return focus
  end,
  setFocus = function(id) focus = id end,
  getFocus = function() return focus end,
  moveFocus = function(_, direction)
    local items, current = interactiveNodes(), nil
    for index, id in ipairs(items) do
      if id == focus then current = index break end
    end
    local step = (direction == "right" or direction == "down") and 1 or -1
    local nextIndex = current and current + step or 1
    if items[nextIndex] then focus = items[nextIndex] end
    return focus
  end,
}

local ui = require("ui")

assert(ui.getTheme() == "light")
assert(table.concat(ui.themeNames(), ",") == "dark,light,mono")
local ok, err = ui.setTheme("missing")
assert(ok == nil and err == "Unknown theme")
assert(ui.setTheme("dark") == true)
assert(files["/.lua/theme"] == "dark" and ui.getTheme() == "dark")

local events = {}
local function handler(name)
  return function(id, x, y)
    events[#events + 1] = {name, id, x, y}
  end
end

local first = ui.button{
  label = "one",
  on_enter = handler("enter"),
  on_exit = handler("exit"),
  on_click = handler("click"),
}
local second = ui.button{
  label = "two",
  on_enter = handler("enter"),
  on_exit = handler("exit"),
  on_click = handler("click"),
}
local screen = ui.screen(ui.box{row = true, first, second})

assert(screen:down(10, 10))
assert(node.isPressed(first))
assert(screen:move(95, 10))
assert(not node.isPressed(first))
assert(screen:move(10, 10))
assert(node.isPressed(first))
assert(screen:up(10, 10))
assert(not node.isPressed(first))

local expectedTouch = {"enter", "exit", "enter", "exit", "click"}
for index, name in ipairs(expectedTouch) do
  local event = events[index]
  assert(event and event[1] == name and event[2] == first)
  assert(event[3] == 10 or event[3] == 95)
  assert(event[4] == 10)
end

events = {}
assert(screen:button("right", true))
assert(screen:button("right", false))
assert(node.getFocus() == first)
assert(screen:button("right", true))
assert(node.getFocus() == second)
assert(screen:button("confirm", true))
assert(node.isPressed(second))
assert(screen:button("confirm", false))
assert(not node.isPressed(second))
assert(screen:button("back", true) == false)

local expectedButtons = {
  {"enter", first},
  {"exit", first},
  {"enter", second},
  {"click", second},
}
for index, expected in ipairs(expectedButtons) do
  local event = events[index]
  assert(event and event[1] == expected[1] and event[2] == expected[2])
  assert(event[3] == nil and event[4] == nil)
end

local before = #invalidated
assert(ui.setTheme("mono") == true)
assert(ui.getTheme() == "mono" and #invalidated == before + 1)
assert(cleared == ui.theme.background)

screen:draw()

-- 320x480 portrait: three columns, and the reserve comes off the height budget.
local side, columns = ui.cardSide(5, 12, 8)
assert(columns == 3 and side == 93, "width is the binding constraint in portrait")
-- Five cards are two rows, so a reserve that eats the height budget shrinks the card.
assert(select(1, ui.cardSide(5, 12, 8, 300)) == 74, "height binds once the reserve is large")

print("ok")