import sys
import click
import logging
import webbrowser

from os.path import splitext, basename


@click.command()
@click.argument('data', metavar='<data file>', type=click.Path(exists=True, file_okay=True, dir_okay=False))
@click.option('--layout', '-l', type=click.Choice(['umap', 'tsne']), default='umap', show_default=True,
              help='Method for layout.')
@click.option('--diffexp', '-d', type=click.Choice(['ttest']), default='ttest', show_default=True,
              help='Method for differential expression.')
@click.option('--title', '-t', help='Title to display (if omitted will use file name).', metavar='')
@click.option('--verbose', '-v', is_flag=True, default=False, show_default=True,
              help='Provide verbose output, including warnings and all server requests.')
@click.option('--debug', '-d', is_flag=True, default=False, show_default=True,
              help='Run in debug mode.')
@click.option('--open', '-o', 'open_browser', is_flag=True, default=False, show_default=True,
              help='Open the web browser after launch.')
@click.option('--port', '-p', help="Port to run server on.", metavar='', default=5005, show_default=True)
@click.option('--obs-names', default=None, metavar='', help='Name of annotation field to use for observations.')
@click.option('--var-names', default=None, metavar='', help='Name of annotation to use for variables.')
@click.option('--listen-all', is_flag=True, default=False, show_default=True,
              help='Bind to all interfaces (this makes the server accessible beyond this computer).')
@click.option('--max-category-items', default=100, metavar='', show_default=True,
              help='Limits the number of categorical annotation items displayed.')
def launch(data, layout, diffexp, title, verbose, debug, obs_names, var_names,
           open_browser, port, listen_all, max_category_items):
    """Launch the cellxgene data viewer.
    This web app lets you explore single-cell expression data.
    Data must be in a format that cellxgene expects, read the
    "getting started" guide.

    Examples:

    > cellxgene launch example_dataset/pbmc3k.h5ad --title pbmc3k

    > cellxgene launch <your data file> --title <your title>"""

    # Startup message
    click.echo('[cellxgene] Starting the CLI...')

    # Import Flask app
    from server.app.app import app

    # Argument checking
    name, extension = splitext(data)
    if extension != '.h5ad':
        raise click.FileError(basename(data), hint='file type must be .h5ad')

    if debug:
        verbose = True
        open_browser = False

    if not verbose:
        sys.tracebacklimit = 0

    if not title:
        file_parts = splitext(basename(data))
        title = file_parts[0]

    if listen_all:
        host = '0.0.0.0'
    else:
        host = '127.0.0.1'

    # Setup app
    cellxgene_url = f"http://{host}:{port}"
    api_base = f"{cellxgene_url}/api/"

    app.config.update(
        DATASET_TITLE=title,
        CXG_API_BASE=api_base
        )

    if not verbose:
        log = logging.getLogger('werkzeug')
        log.setLevel(logging.ERROR)

    click.echo(f'[cellxgene] Loading data from {basename(data)}, this may take awhile...')

    from server.app.scanpy_engine.scanpy_engine import ScanpyEngine

    args = {'layout': layout, 'diffexp': diffexp, 'max_category_items': max_category_items,
            'obs_names': obs_names, 'var_names': var_names}

    app.data = ScanpyEngine(data, args)

    if open_browser:
        click.echo(f'[cellxgene] Launching! Opening your browser to {cellxgene_url} now.')
        webbrowser.open(cellxgene_url)
    else:
        click.echo(f'[cellxgene] Launching! Please go to {cellxgene_url} in your browser.')

    click.echo('[cellxgene] Type CTRL-C at any time to exit.')

    app.run(host=host, debug=debug, port=port)