#!/usr/bin/env python

# Concatenates spreadsheets, removing any duplicated headers

# Usage: self [sheet...] >out_sheet

#

# The existing header can be overwritten by adding a separate header file whose

# header line is prefixed with "!". This is useful if the existing header's

# column names are too long, not descriptive enough, etc.

import os.path

import sys

sys.path.append(os.path.dirname(__file__)+"/../lib")

import csvs

import strings

import util

def main():

    paths = sys.argv[1:]

    header_written = False

    first_path = None

    first_info = None

    for path in paths:

        if path == '-': stream = sys.stdin

        else: stream = open(path, 'rb')

        # Get dialect and process first line

        info = csvs.stream_info(stream)

        try:

            if info.dialect == None: continue # dialect of None = empty stream

            overwrite_ref = [False] # whether to overwrite the existing header

            info.header_line = strings.remove_prefix('!', info.header_line,

                overwrite_ref)

            def write_header(): sys.stdout.write(info.header_line)

            if first_info == None:

                first_path = path

                if not overwrite_ref[0]: first_info = info

                    # otherwise, next header becomes the compare-to header

                if not header_written:

                    write_header()

                    header_written = True

            else:

                if not util.classes_eq(info.dialect, first_info.dialect):

                    raise SystemExit('Spreadsheet error: "'+path

                        +'" dialect doesn\'t match "'+first_path+'" dialect')

                if info.header_line != first_info.header_line: write_header()

                    # not a duplicated header

            # Copy remaining lines

            while True:

                line = stream.readline()

                if line == '': break

                sys.stdout.write(line)

        except IOError, e: # abort if output stream closed

            if str(e) != '[Errno 32] Broken pipe': raise # other IOErrors

        finally: stream.close() # still run if continue is called

main()