"""Used by the make system to generate a rules.mk
"""
from pathlib import Path

from dotty_dict import dotty
from milc import cli

from qmk.info import info_json
from qmk.json_schema import json_load, validate
from qmk.keyboard import keyboard_completer, keyboard_folder
from qmk.keymap import locate_keymap
from qmk.path import normpath


def process_mapping_rule(kb_info_json, rules_key, info_dict):
    """Return the rules.mk line(s) for a mapping rule.
    """
    if not info_dict.get('to_c', True):
        return None

    info_key = info_dict['info_key']
    key_type = info_dict.get('value_type', 'str')

    try:
        rules_value = kb_info_json[info_key]
    except KeyError:
        return None

    if key_type == 'array':
        return f'{rules_key} ?= {" ".join(rules_value)}'
    elif key_type == 'bool':
        return f'{rules_key} ?= {"on" if rules_value else "off"}'
    elif key_type == 'mapping':
        return '\n'.join([f'{key} ?= {value}' for key, value in rules_value.items()])

    return f'{rules_key} ?= {rules_value}'


@cli.argument('-o', '--output', arg_only=True, type=normpath, help='File to write to')
@cli.argument('-q', '--quiet', arg_only=True, action='store_true', help="Quiet mode, only output error messages")
@cli.argument('-e', '--escape', arg_only=True, action='store_true', help="Escape spaces in quiet mode")
@cli.argument('-kb', '--keyboard', arg_only=True, type=keyboard_folder, completer=keyboard_completer, required=True, help='Keyboard to generate rules.mk for.')
@cli.argument('-km', '--keymap', arg_only=True, help='Keymap to generate rules.mk for.')
@cli.subcommand('Used by the make system to generate rules.mk from info.json', hidden=True)
def generate_rules_mk(cli):
    """Generates a rules.mk file from info.json.
    """
    # Determine our keyboard/keymap
    if cli.args.keymap:
        km = locate_keymap(cli.args.keyboard, cli.args.keymap)
        km_json = json_load(km)
        validate(km_json, 'qmk.keymap.v1')
        kb_info_json = dotty(km_json.get('config', {}))
    else:
        kb_info_json = dotty(info_json(cli.args.keyboard))

    info_rules_map = json_load(Path('data/mappings/info_rules.json'))
    rules_mk_lines = ['# This file was generated by `qmk generate-rules-mk`. Do not edit or copy.', '']

    # Iterate through the info_rules map to generate basic rules
    for rules_key, info_dict in info_rules_map.items():
        new_entry = process_mapping_rule(kb_info_json, rules_key, info_dict)

        if new_entry:
            rules_mk_lines.append(new_entry)

    # Iterate through features to enable/disable them
    if 'features' in kb_info_json:
        for feature, enabled in kb_info_json['features'].items():
            if feature == 'bootmagic_lite' and enabled:
                rules_mk_lines.append('BOOTMAGIC_ENABLE ?= lite')
            else:
                feature = feature.upper()
                enabled = 'yes' if enabled else 'no'
                rules_mk_lines.append(f'{feature}_ENABLE ?= {enabled}')

    # Set SPLIT_TRANSPORT, if needed
    if kb_info_json.get('split', {}).get('transport', {}).get('protocol') == 'custom':
        rules_mk_lines.append('SPLIT_TRANSPORT ?= custom')

    # Set CUSTOM_MATRIX, if needed
    if kb_info_json.get('matrix_pins', {}).get('custom'):
        if kb_info_json.get('matrix_pins', {}).get('custom_lite'):
            rules_mk_lines.append('CUSTOM_MATRIX ?= lite')
        else:
            rules_mk_lines.append('CUSTOM_MATRIX ?= yes')

    # Show the results
    rules_mk = '\n'.join(rules_mk_lines) + '\n'

    if cli.args.output:
        cli.args.output.parent.mkdir(parents=True, exist_ok=True)
        if cli.args.output.exists():
            cli.args.output.replace(cli.args.output.parent / (cli.args.output.name + '.bak'))
        cli.args.output.write_text(rules_mk)

        if cli.args.quiet:
            if cli.args.escape:
                print(cli.args.output.as_posix().replace(' ', '\\ '))
            else:
                print(cli.args.output)
        else:
            cli.log.info('Wrote rules.mk to %s.', cli.args.output)

    else:
        print(rules_mk)