from ansible.module_utils.basic import AnsibleModule
import os
import re


def parse_mkinitcpio_line(type: str, line: str) -> list[str]:
    regex = "^" + type + r"=\((.*)\)$"
    result = re.search(regex, line)
    if result is None:
        return None

    return list(filter(lambda v: v != "", result.group(1).split(" ")))


def build_mkinitcpio_line(type: str, values: list[str]) -> str:
    return type + "=(" + " ".join(values) + ")"


def update_mkinitcpio_line(type: str, desired_state: str, values: list[str], line) -> tuple[str, bool]:
    current_values = parse_mkinitcpio_line(type, line)
    changed = False
    if current_values is not None:
        if desired_state == "present":
            for value in values:
                if value not in current_values:
                    current_values.append(value)
                    changed = True
        elif desired_state == "absent":
            for value in values:
                if value in current_values:
                    current_values.remove(value)
                    changed = True
        else:
            raise ValueError("Invalid state: %" % desired_state)

        return build_mkinitcpio_line(type, current_values), changed
    else:
        return None, False


def run_module():
    # define available arguments/parameters a user can pass to the module
    module_args = dict(
        state=dict(default='present', choices=['present', 'absent']),
        binaries=dict(type='list'),
        files=dict(type='list'),
        hooks=dict(type='list'),
        path=dict(type='str', default='/etc/mkinitcpio.conf')
    )

    # seed the result dict in the object
    # we primarily care about changed and state
    # changed is if this module effectively modified the target
    # state will include any data that you want your module to pass back
    # for consumption, for example, in a subsequent task
    result = dict(
        changed=False,
    )

    # the AnsibleModule object will be our abstraction working with Ansible
    # this includes instantiation, a couple of common attr would be the
    # args/params passed to the execution, as well as if the module
    # supports check mode
    module = AnsibleModule(
        argument_spec=module_args,
        supports_check_mode=True
    )

    # if the user is working with this module in only check mode we do not
    # want to make any changes to the environment, just return the current
    # state with no modifications
    if module.check_mode:
        module.exit_json(**result)

    path = module.params['path']
    if not os.path.isfile(path):
        module.fail_json(msg="The path is invalid: %s does not exist" % path)

    state = module.params['state']
    binaries = module.params['binaries']
    files = module.params['files']
    hooks = module.params['hooks']

    file = open(path, "r")
    lines = file.readlines()
    for index, line in enumerate(lines):
        if binaries is not None:
            updated_line, updated = update_mkinitcpio_line(
                "BINARIES", state, binaries, line)
            if updated:
                result['changed'] = True
                if updated_line is not None:
                    lines[index] = updated_line

        if files is not None:
            updated_line, updated = update_mkinitcpio_line(
                "FILES", state, files, line)
            if updated:
                result['changed'] = True
                if updated_line is not None:
                    lines[index] = updated_line

        if hooks is not None:
            updated_line, updated = update_mkinitcpio_line(
                "HOOKS", state, hooks, line)
            if updated:
                result['changed'] = True
                if updated_line is not None:
                    lines[index] = updated_line

    if result['changed']:
        file = open(path, "w")
        file.write("".join(lines))

    # manipulate or modify the state as needed (this is going to be the
    # part where your module will do what it needs to do)
    # in the event of a successful module execution, you will want to
    # simple AnsibleModule.exit_json(), passing the key/value results
    module.exit_json(**result)


def main():
    run_module()


if __name__ == '__main__':
    main()