# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

"""This script is intended to be called through fzf as a preview formatter."""


import argparse
import os
import sys

here = os.path.abspath(os.path.dirname(__file__))
sys.path.insert(0, os.path.join(os.path.dirname(here), "util"))
from estimates import duration_summary


def process_args():
    """Process preview arguments."""
    argparser = argparse.ArgumentParser()
    argparser.add_argument(
        "-s",
        "--show-estimates",
        action="store_true",
        help="Show task duration estimates (default: False)",
    )
    argparser.add_argument(
        "-g",
        "--graph-cache",
        type=str,
        default=None,
        help="Filename of task graph dependencies",
    )
    argparser.add_argument(
        "-c",
        "--cache_dir",
        type=str,
        default=None,
        help="Path to cache directory containing task durations",
    )
    argparser.add_argument(
        "-t",
        "--tasklist",
        type=str,
        default=None,
        help="Path to temporary file containing the selected tasks",
    )
    return argparser.parse_args()


def plain_display(taskfile):
    """Original preview window display."""
    with open(taskfile) as f:
        tasklist = [line.strip() for line in f]
    print("\n".join(sorted(tasklist)))


def duration_display(graph_cache_file, taskfile, cache_dir):
    """Preview window display with task durations + metadata."""
    with open(taskfile) as f:
        tasklist = [line.strip() for line in f]

    durations = duration_summary(graph_cache_file, tasklist, cache_dir)
    output = ""
    max_columns = int(os.environ["FZF_PREVIEW_COLUMNS"])

    output += "\nSelected tasks take {}\n".format(durations["selected_duration"])
    output += "+{} dependencies, total {}\n".format(
        durations["dependency_count"],
        durations["selected_duration"] + durations["dependency_duration"],
    )

    if durations.get("percentile"):
        output += "This is in the top {}% of requests\n".format(
            100 - durations["percentile"]
        )

    output += "Estimated finish in {} at {}".format(
        durations["wall_duration_seconds"], durations["eta_datetime"].strftime("%H:%M")
    )

    duration_width = 5  # show five numbers at most.
    output += "{:>{width}}\n".format("Duration", width=max_columns)
    for task in tasklist:
        duration = durations["task_durations"].get(task, 0.0)
        output += "{:{align}{width}} {:{nalign}{nwidth}}s\n".format(
            task,
            duration,
            align="<",
            width=max_columns - (duration_width + 2),  # 2: space and 's'
            nalign=">",
            nwidth=duration_width,
        )

    print(output)


if __name__ == "__main__":
    args = process_args()
    if args.show_estimates and os.path.isdir(args.cache_dir):
        duration_display(args.graph_cache, args.tasklist, args.cache_dir)
    else:
        plain_display(args.tasklist)