import argparse
import logging
import re
import sys

import pycmx

FORMAT = "%(asctime)-15s %(message)s"
logging.basicConfig(format=FORMAT)


log = logging.getLogger(__name__)


def all_video_edits(edl):
    for event in edl.events:
        for edit in event.edits:
            if edit.channels.video:
                yield edit


def get_scene_name(edit, pattern):
    scene_extractor = re.compile(pattern, re.IGNORECASE)
    if edit.clip_name is None:
        return None
    else:
        match_data = re.match(scene_extractor, edit.clip_name)
        if match_data:
            return match_data[1]
        else:
            return edit.clip_name


def output_cmx(outfile, out_list):
    outfile.write("TITLE:  SCENE LIST\r\n")
    outfile.write("FCM: NON-DROP FRAME\r\n")

    for i, o in enumerate(out_list):
        line = "%03i  AX       V     C        " % (i)
        line += "00:00:00:00 00:00:00:00 %s %s\r\n" % (o["start"], o["end"])
        outfile.write(line)
        outfile.write("* FROM CLIP NAME: %s\r\n" % (o["scene"]))


def output_cols(outfile, out_list):
    for o in out_list:
        outfile.write("%-12s\t%-12s\t%s\n" % (o["start"], o["end"], o["scene"]))


def scene_list(infile, outfile, out_format, pattern):

    edl = pycmx.parse_cmx3600(infile)

    current_scene_name = None

    grouped_edits = []

    for edit in all_video_edits(edl):
        this_scene_name = get_scene_name(edit, pattern)
        if this_scene_name is not None:
            if current_scene_name != this_scene_name:
                grouped_edits.append([])
                current_scene_name = this_scene_name

            grouped_edits[-1].append(edit)

    out_list = []
    for group in grouped_edits:
        out_list.append(
            {
                "start": group[0].record_in,
                "end": group[-1].record_out,
                "scene": get_scene_name(group[0], pattern),
            }
        )

    if out_format == "cmx":
        output_cmx(outfile, out_list)
    if out_format == "cols":
        output_cols(outfile, out_list)
    else:
        log.warning(f"Format {out_format} unrecognized. Will use cmx.\n")
        output_cmx(outfile, out_list)


def scene_list_cli():
    parser = argparse.ArgumentParser(
        description="Read video events from an input CMX EDL and output "
        "events merged into scenes."
    )
    parser.add_argument(
        "-o",
        "--outfile",
        default=sys.stdout,
        type=argparse.FileType("w"),
        help="Output file. Default is stdout.",
    )
    parser.add_argument(
        "-f",
        "--format",
        default="cmx",
        type=str,
        help="Output format. Options are cols and cmx, cmx is the default.",
    )
    parser.add_argument(
        "-p",
        "--pattern",
        default="V?([A-Z]*[0-9]+)",
        help="RE pattern for extracting scene name from clip "
        'name. The default is "V?([A-Z]*[0-9]+)". '
        + "This pattern will be matched case-insensitively.",
    )
    parser.add_argument(
        "input_edl",
        default=sys.stdin,
        type=argparse.FileType("r"),
        nargs="?",
        help="Input file. Default is stdin.",
    )
    args = parser.parse_args()

    infile = args.input_edl

    scene_list(
        infile=infile,
        outfile=args.outfile,
        out_format=args.format,
        pattern=args.pattern,
    )


if __name__ == "__main__":
    scene_list_cli()