#!/usr/bin/env python3

import sys
import re

class Schema:

    def __init__ (self,input,output=None):
        self.input=input
        self.output=output

    # left part is non-greedy
    comment = re.compile("(.*?)--.*")
    spaces = re.compile("^\s+(\S.*)")
    view = re.compile("(?i)\s*create\s+(or\s+replace)?\s+view.*")

    def parse (self):
        if self.output:
            outfile = open(self.output, "a")
        else:
            outfile = sys.stdout
        with open(self.input) as feed:
            contents = feed.read()
        parts = contents.split(";")
        for part in parts:
            # normalize: remove comments, linebreaks, trailing spaces..
            lines = part.split('\n')
            out_lines = []
            for line in lines:
                # remove comment
                match = Schema.comment.match(line)
                if match:
                    line = match.group(1)
                out_lines.append(line)
            # get them together
            out_line = " ".join(out_lines)
            # remove trailing spaces
            match = Schema.spaces.match(out_line)
            if match:
                out_line = match.group(1)
            match = Schema.view.match(out_line)
            if match:
                outfile.write("{};\n".format(out_line))
        if outfile != sys.stdout:
            outfile.close()

if __name__ == '__main__':
    if len(sys.argv) not in [2, 3]:
        print('Usage:', sys.argv[0], 'input [output]')
        sys.exit(1)
    input = sys.argv[1]
    try:
        output = sys.argv[2]
    except Exception:
        output = None
    Schema(input, output).parse()