--[[
    Generally whenever you want to get a position B that is distance units away from position A such that position B is positioned at a specific angle in relation to position A, the pattern is something like: 
    
    bx = ax + distance*math.cos(angle) and by = ay + distance*math.sin(angle).
]]

---@class Player:GameObject
---@field area Area
---@field x number
---@field y number
---@field opts table|nil
local Player = GameObject:extend()

function Player:new(area, x, y, opts)
    Player.super.new(self, area, x, y, opts)

    self.w, self.h = 12, 12
    self.collider = self.area.world:circle(self.x, self.y, math.floor(self.w*0.8))

    -- player angle
    self.r = -math.pi/2
    -- velocity of player angle rotation
    self.rv = 1.66*math.pi
    -- player velocity
    self.v = 0
    -- max player velocity
    self.max_v = 100
    -- player acceleration
    self.a = 100
    -- attack rate
    self.ar = 0.24

    self.timer:every(self.ar, function() self:shoot() end)
end

function Player:update(dt)
    Player.super.update(self, dt)
    if self:isDead() then return end

    -- controls
    if input:down('left') then self.r = self.r - self.rv*dt end
    if input:down('right') then self.r = self.r + self.rv*dt end

    -- update velocity
    self.v = math.min(self.v + self.a*dt, self.max_v)

    -- update position
    local vx = self.v * math.cos(self.r)  -- velocity X
    local vy = self.v * math.sin(self.r)  -- velocity Y
    self.x = self.x + vx * dt             -- update position X
    self.y = self.y + vy * dt             -- update position Y

    -- move collision area
    self.collider:moveTo(self.x, self.y)

    -- offscreen kill
    if self.x < 0-self.w then self:kill() end
    if self.y < 0-self.h then self:kill() end
    if self.x > gw+self.w then self:kill() end
    if self.y > gh+self.h then self:kill() end

    if input:pressed('f11') then self:kill() end
end

function Player:draw()
    Player.super.draw(self)
    if DEBUG then
        love.graphics.setColor(COLORS.collision)
        self.collider:draw()
        love.graphics.setColor(COLORS.debug)
        love.graphics.line(self.x, self.y, self.x + 2*self.w*math.cos(self.r), self.y + 2*self.w*math.sin(self.r))
    end
    love.graphics.setColor(COLORS.default)
    love.graphics.circle('line', self.x, self.y, self.w)
end

function Player:shoot()
    local d = 1.2*self.w
    local offset_x, offset_y = self.x + d*math.cos(self.r), self.y + d*math.sin(self.r)
    self.area:addGameObject('ShootEffect', offset_x, offset_y, {player = self, d = d})
    local proj = self.area:addGameObject('Projectile', offset_x, offset_y, {v = 100 ,r = self.r})
    proj.timer:tween(0.5, proj, {v = 400}, 'linear')
end

function Player:kill()
    self:destroy()
    for i=1, random(8,12) do
        self.area:addGameObject('ExplodeParticle', self.x, self.y)
    end
    self.area:slow(.15, 1)
    camera:shake(6, 60, .4)
end

return Player