View.Set ("graphics:800;600,offscreenonly")
%Variables
var x, hitleftwall, hitrightwall, firedelay, firedelaytime, totalfired, statsenemy : int := 0
var lazerx, lazery, fired : array 1 .. 10 of int
var enemyhp, enemyx, enemyy : array 1 .. 20 of int
var chars : array char of boolean
var mypic : int := Pic.FileNew ("spaceship2.jpg")
var mypic2 : int := Pic.FileNew ("enemy.jpg")
var mypic3 : int := Pic.FileNew ("enemy2.jpg")
var mypic4 : int := Pic.FileNew ("enemy3.jpg")
var mypic5 : int := Pic.FileNew ("bomb.jpg")
var continue : string
var font : int
var diameter : int
diameter := 25
var bomb : int
bomb := 100

%instructions
font := Font.New ("serif:40")
Draw.Text ("INSTRUCTIONS", maxx div 2 - 180, 450, font, red)
font := Font.New ("serif:20")
Draw.Text ("left....  move ship left", maxx div 2 - 120, 350, font, red)
Draw.Text ("right...  move ship right ", maxx div 2 - 120, 320, font, red)
Draw.Text ("up......  shoot laser", maxx div 2 - 120, 290, font, red)
Draw.Text ("down....  shoot bomb", maxx div 2 - 120, 260, font, red)
Draw.Text ("Shoot down all the aliens. Each alien has three lives. After you kill", 20, 190, font, red)
Draw.Text ("all the aliens, you will move on to the next level, where the aliens", 20, 160, font, red)
Draw.Text ("will begin to return fire. Each time you move up a level, you will get", 20, 130, font, red)
Draw.Text ("one bomb, which will randomly take out 3 of the aliens at once.", 20, 100, font, red)
loop
    Draw.Text ("Continue? Press y, then enter to continue onto the game", 20, 40, font, red)
    get continue
    exit when continue = "y"
end loop


%settings
x := 400
statsenemy := 12
colorback (black)
cls
%Sets up the arrays
for count : 1 .. statsenemy
    enemyhp (count) := 3
    enemyx (count) := 50 + (50 * count)
    enemyy (count) := 500
end for
for count : 1 .. 10
    fired (count) := 0
end for


loop
    Input.KeyDown (chars)
    %Handles shooting the lazer
    if chars (KEY_UP_ARROW) then
        if firedelay = 0 then
            if totalfired <= 9 then
                totalfired += 1
                fired (totalfired) := 1
                firedelay := 1
                lazerx (totalfired) := x + 25
                lazery (totalfired) := 35
            end if
        end if
    end if

    %Moves tank to the right
    if chars (KEY_RIGHT_ARROW) then
        if hitrightwall = 0 then
            x := x + 5
        end if
    end if
    %Moves tank to the left
    if chars (KEY_LEFT_ARROW) then
        if hitleftwall = 0 then
            x := x - 5
        end if
    end if
    %To be used for special move sometime in future (like a bomb)

    if chars (KEY_DOWN_ARROW) then
        Pic.Draw (mypic5, 150, 0, 0)
        bomb := bomb - 1
        if bomb = 50 then
            statsenemy := statsenemy - 3
        end if
    end if


    %Collision detection with the left and right walls.
    if x <= 25 then
        hitleftwall := 1
    elsif x >= 775 then
        hitrightwall := 1
    else
        hitrightwall := 0
        hitleftwall := 0
    end if
    %Creates a delay so that bullets can only fire every 10 frames.
    if firedelay = 1 then
        if firedelaytime < 10 then
            firedelaytime += 1
        else
            firedelaytime := 0
            firedelay := 0
        end if
    end if
    %Checks for collision with enemy and lazer
    for count : 1 .. statsenemy
        for count1 : 1 .. upper (fired)
            if fired (count1) = 1 then
                if lazery (count1) >= enemyy (count) - 10 and lazerx (count1) = enemyx (count) - 30 or lazery (count1) <= enemyy (count) - 7 and lazerx (count1) = enemyx (count) + 30 then
                    fired (count) := 0
                    totalfired := 0
                    if enemyhp (count) >= 1 then
                        enemyhp (count) -= 1
                    end if
                end if
            end if
        end for
    end for
    %Draws enemys with correct color
    for count : 1 .. statsenemy
        if enemyhp (count) = 3 then
            Pic.Draw (mypic2, (enemyx (count)), (enemyy (count)), 0)
        elsif enemyhp (count) = 2 then
            Pic.Draw (mypic3, (enemyx (count)), (enemyy (count)), 0)
        elsif enemyhp (count) = 1 then
            Pic.Draw (mypic4, (enemyx (count)), (enemyy (count)), 0)
        end if
    end for

    %Draws lazers and checks if they are off the screen.
    for count : 1 .. upper (fired)
        if fired (count) = 1 then
            if lazery (count) <= 775 then
                lazery (count) += 5
                drawline (lazerx (count), lazery (count), lazerx (count), lazery (count) + 5, white)
            else
                fired (count) := 0
                totalfired := 0
            end if
        end if
    end for

    %Checks if enemy is hit by lazer and then deletes lazer and takes away the hp.
    for count : 1 .. statsenemy
        for count1 : 1 .. upper (fired)
            if fired (count1) = 1 then
                if lazery (count1) >= enemyy (count) - 10 and lazerx (count1) = enemyx (count) - 30 or lazery (count1) <= enemyy (count) - 7 and lazerx (count1) = enemyx (count) + 30 then
                    fired (count) := 0
                    totalfired := 0
                    if enemyhp (count) >= 1 then
                        enemyhp (count) -= 1
                    end if
                end if
            end if
        end for
    end for
    %Draws player
    Pic.Draw (mypic, x, 30, 0)

    View.Update
    delay (10)
    cls
end loop