#!/usr/bin/env python
"""
colgrep: Interactive grep-like tool that hi-lights results.

Usage: colgrep [-d] <extended-regexp> [files]
"""

import re
import sys

COLSTRING="\x1b[%sm"

def main():
    debug = 0
    if '-d' in sys.argv:
        debug = 1
        sys.argv.remove("-d")

    # FIXME: Error check
    regexp = sys.argv[1]
    prog = re.compile(regexp)

    errs = [prog.groupindex[key] for key in prog.groupindex.keys() 
            if key.startswith("err")]

    for fn in sys.argv[2:]:
        f = open(fn)
        for line in f.readlines():
            line = line[:-1]
            match = prog.search(line)
            if match:
                starts = {}
                ends = {}
                if prog.groups == 0:
                    starts.setdefault(match.start(), []).append(1)
                    ends.setdefault(match.end() - 1, []).insert(0,1)
                else:
                    cnt = 1
                    for group in match.groups():
                        col = ""
                        if cnt in errs:
                            col = COLSTRING % (41 + (cnt % 5))
                        else:
                            col += COLSTRING % (31 + (cnt % 5))
                        if group is not None and group != "":
                            starts.setdefault(match.start(cnt), []).append(col)
                            ends.setdefault(match.end(cnt) - 1, []).insert(0,col)
                        cnt += 1

                cnt = 0
                color_stack = [0]
                sys.stdout.write("%-60s| " % fn)
                for ch in line:
                    if cnt in starts:
                        for color in starts[cnt]:
                            color_stack.append(color)
                            sys.stdout.write('%s' % color_stack[-1])
                            if debug:
                                sys.stdout.write("{")
                        del starts[cnt]
                    sys.stdout.write(ch)
                    if cnt in ends:
                        for x in ends[cnt]:
                            del color_stack[-1]
                            if debug:
                                sys.stdout.write("}")
                            sys.stdout.write('\x1b[%sm' % color_stack[-1])
                        del ends[cnt]
                    cnt += 1
                sys.stdout.write("\n")

if __name__ == "__main__":
    main()