#! /usr/bin/env python

import os
import glob


# =========================== #
# Read license text from file #
# =========================== #
def read_license(filename):
    """
    Read license text from file.
    """
    # Initialise lines
    lines = []

    # Loop over file
    for line in open(filename, 'r'):
        if len(line.rstrip("\n").strip(" ")) > 0:
            lines.append(line)

    # Return lines
    return lines


# ==================== #
# Replace license text #
# ==================== #
def replace_license(filename, license_old, license_new):
    """
    Replace license text in file.
    """
    # Set temporary name
    tmpname = "test.txt"

    # Open temporary file
    file = open(tmpname, "w")

    # Initialise old text line finder
    ifind = 0

    # Loop over file
    for line in open(filename, 'r'):

        # Search line for license text
        if line == license_old[ifind]:
            ifind += 1
            if ifind >= len(license_old):
                for replace in license_new:
                    file.write(replace)
                print "License text upated in file " + filename + "."
                ifind = 0

        # Handle partial license text
        elif ifind > 0:
            print "Partial old license text found in file " + filename + ". Ignored."
            ifind = 0

        # ... otherwise write out line
        else:
            file.write(line)

    # Close temporary file
    file.close()

    # Replace input file
    os.rename(tmpname, filename)

    # Return
    return


# ======================================================== #
# Replace license text in files with name given by pattern #
# ======================================================== #
def update_files(pattern, license_old, license_new):
    """
    Replace license text in files with name given by pattern.
    """
    # Get sorted list of files
    files = glob.glob(pattern)
    files.sort()

    # Loop over all files
    for file in files:
        replace_license(file, license_old, license_new)

    # Return
    return


# ======================== #
# Main routine entry point #
# ======================== #
if __name__ == '__main__':
    """
    Replace old by new license text.
    """
    # Load license files
    license_old = read_license("license_old.txt")
    license_new = read_license("license_new.txt")

    # Replace license text
    update_files("include/*.hpp", license_old, license_new)
    update_files("pyext/*.i", license_old, license_new)
    update_files("src/*/*.*pp", license_old, license_new)
    update_files("inst/*/include/*.hpp", license_old, license_new)
    update_files("inst/*/pyext/*.i", license_old, license_new)
    update_files("inst/*/src/*.cpp", license_old, license_new)
    update_files("inst/*/test/*.*pp", license_old, license_new)
    update_files("test/*.*pp", license_old, license_new)