require("common.class")

---@class Field
---@field parent Page|ContainerField
---@field posX number
---@field posY number
---@field aabbW number
---@field aabbH number
---@field focused boolean
---@field active boolean
local Field = {
    __name = "Field"
}

---Create a new Field instance
---@param params? Field # initial parameters
---@return Field
function Field.new(params)
    params = params or {}

    --set instance members

    params.parent = params.parent or nil
    params.posX = params.posX or 0
    params.posY = params.posY or 0
    params.aabbW = params.aabbW or 0
    params.aabbH = params.aabbH or 0
    params.focused = params.focused or false
    params.active = params.active or false

    return CreateInstance(Field, params)
end

function Field:init()
    self:onInit()
end

---Get the containing top-level parent page
---@return Field|Page
function Field:getParentPage()
    if self.parent and self.parent.getParentPage then
        return self.parent:getParentPage()
    else
        return self.parent
    end
end

function Field:activate()
    self.active = true
    self:onActivated()
end

function Field:focus()
    self.focused = true
    self:onFocusChange(self.focused)
end

function Field:unfocus()
    self.focused = false
    self:onFocusChange(self.focused)
end

function Field:deactivate()
    self.active = false
    self:onDeactivated()
end

---@param button integer # options are under the `game` table prefixed with `BUTTON`
---@return boolean # true if further button input processing should be stopped, otherwise false
function Field:handleButtonInput(button)
    return false
end

---@param knob integer # `0` = Left, `1` = Right
---@param delta number # in radians, `-2*pi` to `0` (turning CCW) and `0` to `2*pi` (turning CW)
---@return boolean # true if further button input processing should be stopped, otherwise false
function Field:handleKnobInput(knob, delta)
    return false
end

---@param x number
---@param y number
---@param button integer
---@return boolean # true if further button input processing should be stopped, otherwise false
function Field:handleMouseInput(x, y, button)
    return false
end

function Field:onInit() end

function Field:onActivated() end

---Callback function for focus change event
---@param focus boolean # weather the field is focused
function Field:onFocusChange(focus) end

function Field:onDeactivated() end

---@param deltaTime number # frametime in seconds
function Field:drawContent(deltaTime)
    -- dummy field content

    gfx.ResetScissor()

    local offX = -50
    local offY = -50
    local aabbW = 100
    local aabbH = 100

    gfx.BeginPath()
    gfx.FillColor(255, 0, 128, 192)
    gfx.StrokeColor(0, 0, 0)
    gfx.StrokeWidth(2)
    gfx.Rect(offX, offY, aabbW, aabbH)
    gfx.Fill()
    gfx.Stroke()

    gfx.BeginPath()
    gfx.MoveTo(offX, 0)
    gfx.LineTo(offX + aabbW, 0)
    gfx.MoveTo(0, offY)
    gfx.LineTo(0, offY + aabbH)
    gfx.StrokeColor(0, 0, 0, 64)
    gfx.StrokeWidth(2)
    gfx.Stroke()

    local fontSize = 18
    local fontMargin = 4
    gfx.BeginPath()
    gfx.FontSize(fontSize)
    gfx.LoadSkinFont("dfmarugoth.ttf")
    gfx.FillColor(0, 0, 0)
    gfx.TextAlign(gfx.TEXT_ALIGN_CENTER | gfx.TEXT_ALIGN_MIDDLE)
    gfx.Text("TEXTURE", 0, -fontSize / 2 - fontMargin)
    gfx.Text("MISSING", 0, fontSize / 2 + fontMargin)
end

---@param deltaTime number # frametime in seconds
function Field:render(deltaTime)
    gfx.Save()

    gfx.Translate(self.posX, self.posY)
    gfx.Scissor(0, 0, self.aabbW, self.aabbH)

    self:drawContent(deltaTime)

    gfx.Restore()
end

return Field