-- title:  einhander
-- author: pixelbath
-- desc:   one-handed
-- script: lua

seed=12345
player={
	x=20, y=50,
    inv=0,
    show=1,
	fire=0,
	gun_down=0,
    gun_anim=0,
    gun_held=0,
}
gunsprites={
    292, -- vulcan
    294, -- cannon
    296, -- spreader
    298, -- wasp
    300, -- grenade
    302, -- hedgehog
}
gunnames={
    {324, "V", "ULCAN"},
    {325, "C", "ANNON"},
    {326, "S", "PREADER"},
    {327, "W", "ASP"},
    {328, "G", "RENADE"},
    {329, "H", "EDGEHOG"},
}
vulcanMuzzleSprites={
    264, 266, 280
}
shellParticles={}
-- particles are just white pixels by default
for i=1,15 do
    table.insert(shellParticles, {x=0,y=0,vx=0,vy=0,age=0,dieAt=0,color=12,idx=0,isPixel=true})
end
particlePointer=1 -- points at the next particle to be spawned

weaponBgSize=16--12
weaponBgTimer=0
weaponAmmo=3000

p_bullets = {}
p_big_bullets = {}
multiplier = 12
multiplier_sub = 0
multiplier_tick = 0
score = 25000

t=0
math.randomseed(seed)

function drawParallelogram(x, y, w, h, skewpx, color)
    tri(x+skewpx, y, x+w, y+h, x, y+h, color)
    tri(x+skewpx, y, x+w, y+h, x+w+skewpx, y, color)
end

function spawnPixelParticle(x, y, vx, vy, age, dieAt, color)
    local p = shellParticles[particlePointer]
    p.x = x
    p.y = y
    p.vx = vx
    p.vy = vy
    p.age = age
    p.dieAt = dieAt
    p.color = color
    p.isPixel = true
    particlePointer = particlePointer + 1
    if particlePointer > 15 then particlePointer = 1 end
end
function spawnSpriteParticle(x, y, vx, vy, age, dieAt, index)
    local p = shellParticles[particlePointer]
    p.x = x
    p.y = y
    p.vx = vx
    p.vy = vy
    p.age = age
    p.dieAt = dieAt
    p.idx = index
    p.isPixel = false
    particlePointer = particlePointer + 1
    if particlePointer > 15 then particlePointer = 1 end
end

function drawPlayer()
    if (player.show) then
        -- arm
        if player.gun_down then
            spr(260, player.x+12, player.y+11, 0, 1, 0, 0, 2, 1)
        else
            spr(260, player.x+12, player.y-2, 0, 1, 2, 0, 2, 1)
        end

        -- ship
        spr(256, player.x, player.y, 0, 1, 0, 0, 4, 2)
    end
    -- draw regular bullets
    for key,val in ipairs(p_bullets) do
        spr(262, val.x, val.y, 0)
    end

    -- custom routines depending on gun held
    if player.gun_held > 0 then
        local gunsprite = gunsprites[player.gun_held]
        local gunpos = player.y - 2
        if player.gun_down then
            gunsprite = gunsprite + 16
            gunpos = gunpos + 14
        end
        spr(gunsprite, player.x+12, gunpos, 0, 1, 0, 0, 2, 1)
        
        -- vulcan
        if player.gun_held == 1 then
            local flipfire = 0
            local muzzleIdx = math.random(0,3)
            if math.random(1, 2) == 2 then
                flipfire = 2
            end
            if player.fire == 0 then
                player.fire = 2
            else
                player.fire = player.fire - 1
            end
            -- begin dakka
            if muzzleIdx > 0 then
                if player.gun_down then
                    spr(vulcanMuzzleSprites[muzzleIdx], player.x + 27, player.y + 14, 0, 1, flipfire, 0, 2, 1)
                else
                    spr(vulcanMuzzleSprites[muzzleIdx], player.x + 28, player.y - 2, 0, 1, flipfire, 0, 2, 1)
                end
            end
            if t % 10 == 0 then
                local randFactor = math.random(10,100)
                local spawnOffsetY = 1

                local lineStart = math.random(player.x+20, 260)
                if player.gun_down then
                    spawnOffsetY = 18
                    -- vulcan tilts downward so we get to do trig! yay!
                    lineStart = lineStart - player.x
                    local angle = 8
                    local radius2 = lineStart+38
                    local c = math.cos(angle * math.pi / 180)
                    local s = math.sin(angle * math.pi / 180)
                    line(c * lineStart + player.x + 18, s * lineStart + player.y + 17, c * radius2 + player.x + 18, s * radius2 + player.y + 17, 14)
                else
                    line(lineStart, player.y+1, lineStart+40, player.y+1, 14)
                end

                -- shells
                spawnPixelParticle(player.x+14, player.y+spawnOffsetY, -0.2, -0.6 + (randFactor / 100), 0, 50, 15)
            end
            -- update shells with light gravity
            for i=1,#shellParticles do
                local p = shellParticles[i]
                p.vy = p.vy + 0.1
            end
        end
    end

    for i=1,#shellParticles do
        local p = shellParticles[i]
        if p.age < p.dieAt then
            if p.isPixel then
                pix(p.x, p.y, p.color)
            else
                spr(p.idx, p.x, p.y)
            end
        end
    end
end

function drawUI()
    -- weapon bg
    -- spr(322, 4, 114, 0, 1, 0, 0, 1, 2)
    -- rect(12, 114, 8, 16, 6)
    -- spr(323, 20, 114, 0, 1, 0, 0, 1, 2)
    drawParallelogram(6, 115, weaponBgSize, 12, 6, 6)

    -- selected weapon
    if player.gun_held > 0 then
        local lettersprite = gunnames[player.gun_held][1]
        local guntext = gunnames[player.gun_held][3]
        spr(lettersprite, 14, 118, 0, 1)
        print(guntext, 24, 122, 12, true, 1, true)
        print(weaponAmmo, 12, 129, 12, true, 1, true)
    end

    -- multiplier
    -- TODO: need to do multipliers over 10, so the X needs to move left when that happens
    spr(340, 164, 114, 0)
    --spr(340 + multiplier, 172, 113, 0)
    spr(330, 180, 114, 0, 1, 0, 0, 4, 1)
    spr(331, 212, 114, 0, 1, 0, 0, 3, 1)
    spr(334, 236, 114, 0, 1)
    if multiplier_sub > 0 then
        for i = 1, multiplier_sub do
            spr(335, 177 + (i * 6), 114, 0)
        end
    end
    
    -- score
    local scorestring = tostring(score)
    for i = 1, #scorestring do
        local char = scorestring:sub(i, i)
        local numsprite = 340 + tonumber(char)
        -- this is a hack because I ordered the numbers weirdly
        if char == "0" then numsprite = 350 end
        spr(numsprite, (230 - (8 * #scorestring)) + (i * 8), 123, 0)
    end
end

-- 1xxxxxxxxxxx
-- 0xxxxxxxxxxx
-- 0xxxxxxxxxxx
-- 1xxxxxxxxxxx
function drawWater(waterHeight)
    for i=0,waterHeight-1 do
        local row = (135 - i - waterHeight) * 120
        local rowDest = (135 + i - waterHeight + 1) * 120
        memcpy(rowDest, row, 120)
    end
end

function drawDebug()
    -- print("p.gdown: " .. tostring(player.gun_down), 5, 5, 12, true, 1, true)
    -- print("spr: " .. tostring(vulcanMuzzleSprites[player.fire + 1]), 5, 13, 12, true, 1, true)
end

function update()
    if btn(0) then
        if player.y > 0 then
            player.y=player.y-2
        end
	end
    if btn(1) then
        if player.y < 120 then
            player.y=player.y+2
        end
	end
    if btn(2) then
        if player.x > 1 then
            player.x=player.x-2
        end
	end
	if btn(3) then
        if player.x < 216 then
            player.x=player.x+2
        end
    end
    if btnp(4) then
        player.gun_held = 1
        player.gun_down = not player.gun_down
    end
    if btn(5) then
        --if player.gun_held == 0 then
            if player.fire == 0 then
                player.fire = 5
                table.insert(p_bullets, {x=player.x+10, y=player.y+2})
            else
                player.fire = player.fire - 1
            end
        --end
    end
    for key,val in ipairs(p_bullets) do
        p_bullets[key].x = p_bullets[key].x + 8
        if val.x > 240 then
            table.remove(p_bullets, key)
        end
    end
    for i=1,#shellParticles do
        local p = shellParticles[i]
        p.x = p.x + p.vx
        p.y = p.y + p.vy
        p.age = p.age + 1
    end

    t=t+1
end

function TIC()
    update()
    cls(0)
    drawPlayer()
    -- drawWater(10)
    drawUI()
    drawDebug()
end