# BLUE KENUE channel mesh.t3s to CCHE2D mesh.geo --Clemens Dorfmann--
#---------------------------------------------------------------------#

# Give here the filenames for Input and Output files:

Input_file = 'Mesh_j10.t3s'
Output_file = 'Mesh_j10.t3s.geo'

# give here the number of crosswise channel nodes j!
j = 10

#---------------------------------------------------------------------#

# read BlueKenue t3s mesh file file
BK_file = open(Input_file, 'r')
BK_text = BK_file.readlines()
BK_file.close()

# initialisation of some empty lists
liste_x_BK = []
liste_y_BK = []
liste_z_BK = []
liste_x_CC = []
liste_y_CC = []
liste_z_CC = []
liste_i = []
liste_j = []
line_noden = []

# get total number of nodes and number of streamwise nodes i
hE = BK_text.index(':EndHeader\n')
line_noden.append(BK_text[hE-4].split())
nodenumbers = int(line_noden[0][1])

i = nodenumbers / j

# delete header and connectivity table in BlueKenue t3s format
del BK_text[:hE+1]
del BK_text[nodenumbers:]

# read x y z values into lists
for lines in BK_text:
    BK_text = lines.split()
    liste_x_BK.append(float(BK_text[0]))
    liste_y_BK.append(float(BK_text[1]))
    liste_z_BK.append(float(BK_text[2]))

for k in range(i):
    liste_x_CC += liste_x_BK[k::i]
    liste_y_CC += liste_y_BK[k::i]
    liste_z_CC += liste_z_BK[k::i]

# fill columns 3, 5 and 6
col_3 = [1.0] * i * j   # water surface level
col_5 = [0] * i * j   # boundary conditions
col_6 = [0.0] * i * j   # manning roughness values

# write to CCHE2D geo file
CCHE2D_file= open(Output_file, 'w')

CCHE2D_file.write(str(j) + '\t' + str(i) + '\n')

for k in range(i*j):
    CCHE2D_file.write(str(liste_x_CC[k]) + '\t' + str(liste_y_CC[k]) + '\t' + str(col_3[k])   \
            + '\t' + str(liste_z_CC[k]) + '\t' + str(col_5[k]) + '\t' + str(col_6[k]) + '\n')

CCHE2D_file.close()