ui.lua

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-- Code related to drawing the UI (user interface)
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function drawUI()

    love.graphics.setColor(1, 1, 1, 1)

    -- rectangle for health bars and around play area
    love.graphics.rectangle('line', 2, 2, WIDTH - 4, 30)
    love.graphics.rectangle('line', 2, 32, WIDTH - 4, HEIGHT - 34)

    drawShootButton()

    drawLives()

    drawHealthBars()

    love.graphics.setColor(1, 1, 1, 1)

end

-- shoot BUTTON rectangle -- change states while shot in progress
function drawShootButton()

    if shotInProgress == true then
        love.graphics.setColor(0.5, 0, 0, 1)
        love.graphics.ellipse('fill', WIDTH - 50, HEIGHT - 50, 30, 30)
    else
        love.graphics.setColor(16 / 255, 178 / 255, 197 / 255, 1)
        love.graphics.ellipse('fill', WIDTH - 50, HEIGHT - 50, 30, 30)
    end

end

-- draw how many lives each has
function drawLives()

    love.graphics.setColor(1, 1, 0, 1)
    for i = 1, player1.lives do
        love.graphics
            .ellipse('fill', WIDTH / 2 + 35 + 20 * i, 16, 8, 8)
    end

    for i = 1, player2.lives do
        love.graphics
            .ellipse('fill', WIDTH / 2 - 35 - 20 * i, 16, 8, 8)
    end

end

-- draw health bars - responsive depending on WIDTH
function drawHealthBars()

    topOffset = 10

    barWidth = WIDTH / 2 - 200

    -- right health bar
    love.graphics.setColor((255 - player1.health * 2.55) / 255, 1, 0, 1)
    love.graphics.rectangle('fill', WIDTH / 2 + 150, topOffset, barWidth, 10)

    if player1.health < 100 then
        love.graphics.setColor(223 / 255, (45 + player1.health) / 255,
                               (45 + player1.health) / 255, 1)
        love.graphics.rectangle('fill', (WIDTH / 2 + 150) + barWidth - barWidth *
                                    ((100 - player1.health) / 100), topOffset,
                                barWidth - barWidth * ((player1.health) / 100), 10)
    end

    -- left health bar
    love.graphics.setColor((255 - player2.health * 2.55) / 255, 1, 0, 1)
    love.graphics.rectangle('fill', WIDTH / 2 - barWidth - 150, topOffset, barWidth, 10)

    if player2.health < 100 then
        love.graphics.setColor(224 / 255, (45 + player2.health) / 255,
                               (45 + player2.health) / 255, 1)
        love.graphics.rectangle('fill', (WIDTH / 2 - barWidth - 150), topOffset,
                                barWidth - barWidth * ((player2.health) / 100), 10)
    end

end

function drawForceAndAngle(playerN, tempHack)

    -- different offset depending on player
    if tempHack == 1 then
        xOffset = playerN.x - 140
        angleY = playerN.y + 80
        forceY = playerN.y + 92
    else
        xOffset = playerN.x + 55
        angleY = playerN.y + 78
        forceY = playerN.y + 90
    end

    -- black background behind angle and force
    love.graphics.setColor(0, 0, 0, 0.7)
    love.graphics.rectangle('fill', xOffset + 12, angleY, 70, 13, 4, 4)
    love.graphics.rectangle('fill', xOffset + 24, forceY + 1, 66, 12, 4, 4)

    -- print force (red)
    love.graphics.setColor(1, 0, 0, 1)
    love.graphics.setFont(pixelFont, 20)
    love.graphics.print('GJ', xOffset + 76, forceY) -- GigaJoules
    love.graphics.printf(string.format("%.5f", playerN.force), xOffset, forceY, 75, 'right')

    -- print angle (white)
    love.graphics.setColor(1, 1, 1, 1)
    love.graphics.printf(string.format("%.5f", 360 - playerN.angle), xOffset, angleY, 75, 'right')
    love.graphics.ellipse('line', xOffset + 78, angleY + 3, 2, 2)

end


function drawShips()

    -- in the user interface (top left and top right)
    love.graphics.draw(ss1, 24, 11)
    love.graphics.draw(ss2, WIDTH - 32, 11)

    -- love.graphics.setColor(1, 0.6, 0.6, 1)
    -- love.graphics.ellipse('fill', player1.x, player1.y, 8, 8)
    -- love.graphics.ellipse('fill', player2.x, player2.y, 8, 8)

    if player1.health > 0 then
        love.graphics.draw(ss1, player1.x - 4, player1.y - 4)
    end
    
    if player2.health > 0 then
        love.graphics.draw(ss2, player2.x - 4, player2.y - 4)
    end

    -- love.graphics.draw(ss1, player1.x, player1.y, player1.angle, 1, 1, 4, 4)

end

--[[
    Dim all the shot trails on the screen
    meant to run after every shot
    works by drawing a black rectangle with low opacity over the whole screen
    then redraws all other elements on top
--]]
function dimTrails()

    print("dimTrails EXECUTED")

    love.graphics.setCanvas(canvas)
    love.graphics.setColor(0, 0, 0, 0.15) -- don't fortget to reset ?
    love.graphics.rectangle('fill', 0, 0, WIDTH, HEIGHT)
    love.graphics.setColor(1, 1, 1, 1) -- reset back !?
    drawPlanets() -- execute inside `canvas` ?!
    drawShips()
    drawUI()
    love.graphics.setCanvas() -- reset canvas ?!

end

function drawPlanets()

    for i = 1, numOfPlanets do
        love.graphics.setColor(0.1, 0.1, 0.1, 1)
        love.graphics.ellipse('fill', allPlanets[i].x, allPlanets[i].y,
                              allPlanets[i].r, allPlanets[i].r)
        love.graphics.setColor(1, 1, 1, 1)
        love.graphics.ellipse('line', allPlanets[i].x, allPlanets[i].y,
                              allPlanets[i].r, allPlanets[i].r)
    end

end