# Asta iti trebe ca din calcule uneori poate sa treaca de intervalu [0. 255] si da eroare poza ca nu stie culori decat in intervalu asta asa ca le pui tu in interval
def clamp(value):
    return int(max(min(value, 255), 0))

# Iei blocku de 8x8 din matrice care incepe la i,j(are coltu stanga sus in i,j)
def get8x8Block(matrix, i, j):
    block = []

    for ii in range(8):
        row = []
        for jj in range(8):
            row.append(matrix[i + ii][j + jj])
        block.append(row)

    return block


def convertYUVtoRGB(y, u, v):
    # B = 1.164(Y - 16) + 2.018(U - 128)
    # G = 1.164(Y - 16) - 0.813(V - 128) - 0.391(U - 128)
    # R = 1.164(Y - 16) + 1.596(V - 128)

    b = 1.164 * (y - 16) + 2.018 * (u - 128)
    g = 1.164 * (y - 16) - 0.813 * (v - 128) - 0.391 * (u - 128)
    r = 1.164 * (y - 16) + 1.596 * (v - 128)

    return r, g, b


def convertRGBtoYUV(r, g, b):
    # Y = 0.299 * R + 0.587 * G + 0.114 * B
    # U = 128 - 0.1687 * R - 0.3312 * G + 0.5 * B
    # V = 128 + 0.5 * R - 0.4186 * G - 0.0813 * B

    y = 0.299 * r + 0.587 * g + 0.114 * b
    u = 128 - 0.1687 * r - 0.3312 * g + 0.5 * b
    v = 128 + 0.5 * r - 0.4186 * g - 0.0813 * b

    return y, u, v


def convertFrom8x8Blocks(matrix, blocks, width, function=lambda x: x):
    for idx, block in enumerate(blocks):
        # Asta e formula ca sa gasesti coltu stanga sus in matricea ta unde vine pus blocu ala. Faci (width/8) pentru ca atatea blocuri ai pe un rand si dupa inmultesti iar cu 8 pentru ca blocurile sunt de 8x8
        row_number = idx // (width / 8) * 8
        col_number = idx % (width / 8) * 8
        # Pentru U si V faci upsample daca e data functia ca param si pentru Y se aplica lambda aia si ramane la fel
        sample = function(block)
        for i in range(8):
            for j in range(8):
                matrix[row_number + i][col_number + j] = sample[i][j]

    return matrix


def createBlocks(matrix, height, width, function=lambda x: x):
    blocks = []

    for i in range(0, height, 8):
        for j in range(0, width, 8):
            # Aici pui blocku in lista si daca e U sau V ii faci downsample daca nu se aplica lamba aia si mane la fel
            blocks.append(function(get8x8Block(matrix, i, j)))

    return blocks


def downSample(block):
    sample = []
    # Iei 2x2 colutile si le faci media si iti iese un bloc si asa din 8x8 -> 4x4
    for i in range(0, 8, 2):
        row = []
        for j in range(0, 8, 2):
            average = (block[i][j] + block[i + 1][j] + block[i][j + 1] + block[i + 1][j + 1]) / 4
            row.append(average)
        sample.append(row)

    return sample


def upSample(block):
    sample = []
    #Dublezi cam toate valorile de 2 ori o data pe linie si o data pe coloana
    for i in range(4):
        row = []
        for j in range(4):
            row.append(block[i][j])
            row.append(block[i][j])
        sample.append(row)
        sample.append(row)

    return sample


def printBlocks(blocks):
    for block in blocks:
        print('--------BlockStart--------')
        for line in block:
            print(line)
        print('--------EndStart--------')