import string
from collections import defaultdict
from typing import Any, Dict, List, Optional, Tuple

TOPIC_WITH_BRANCH_TEMPLATE = "{repo} / {branch}"
TOPIC_WITH_PR_OR_ISSUE_INFO_TEMPLATE = "{repo} / {type} #{id} {title}"
TOPIC_WITH_RELEASE_TEMPLATE = "{repo} / {tag} {title}"

EMPTY_SHA = "0000000000000000000000000000000000000000"

COMMITS_LIMIT = 20
COMMIT_ROW_TEMPLATE = "* {commit_msg} ([{commit_short_sha}]({commit_url}))\n"
COMMITS_MORE_THAN_LIMIT_TEMPLATE = "[and {commits_number} more commit(s)]"
COMMIT_OR_COMMITS = "commit{}"

PUSH_PUSHED_TEXT_WITH_URL = "[{push_type}]({compare_url}) {number_of_commits} {commit_or_commits}"
PUSH_PUSHED_TEXT_WITHOUT_URL = "{push_type} {number_of_commits} {commit_or_commits}"

PUSH_COMMITS_BASE = "{user_name} {pushed_text} to branch {branch_name}."
PUSH_COMMITS_MESSAGE_TEMPLATE_WITH_COMMITTERS = (
    PUSH_COMMITS_BASE
    + """ {committers_details}.

{commits_data}
"""
)
PUSH_COMMITS_MESSAGE_TEMPLATE_WITHOUT_COMMITTERS = (
    PUSH_COMMITS_BASE
    + """

{commits_data}
"""
)
PUSH_DELETE_BRANCH_MESSAGE_TEMPLATE = (
    "{user_name} [deleted]({compare_url}) the branch {branch_name}."
)
PUSH_LOCAL_BRANCH_WITHOUT_COMMITS_MESSAGE_TEMPLATE = (
    "{user_name} [{push_type}]({compare_url}) the branch {branch_name}."
)
PUSH_LOCAL_BRANCH_WITHOUT_COMMITS_MESSAGE_WITHOUT_URL_TEMPLATE = (
    "{user_name} {push_type} the branch {branch_name}."
)
PUSH_COMMITS_MESSAGE_EXTENSION = "Commits by {}"
PUSH_COMMITTERS_LIMIT_INFO = 3

FORCE_PUSH_COMMITS_MESSAGE_TEMPLATE = (
    "{user_name} [force pushed]({url}) to branch {branch_name}. Head is now {head}."
)
CREATE_BRANCH_MESSAGE_TEMPLATE = "{user_name} created [{branch_name}]({url}) branch."
CREATE_BRANCH_WITHOUT_URL_MESSAGE_TEMPLATE = "{user_name} created {branch_name} branch."
REMOVE_BRANCH_MESSAGE_TEMPLATE = "{user_name} deleted branch {branch_name}."

PULL_REQUEST_OR_ISSUE_MESSAGE_TEMPLATE = "{user_name} {action} [{type}{id}]({url})"
PULL_REQUEST_OR_ISSUE_MESSAGE_TEMPLATE_WITH_TITLE = (
    "{user_name} {action} [{type}{id} {title}]({url})"
)
PULL_REQUEST_OR_ISSUE_ASSIGNEE_INFO_TEMPLATE = "(assigned to {assignee})"
PULL_REQUEST_REVIEWER_INFO_TEMPLATE = "(assigned reviewers: {reviewer})"
PULL_REQUEST_BRANCH_INFO_TEMPLATE = "from `{target}` to `{base}`"

CONTENT_MESSAGE_TEMPLATE = "\n~~~ quote\n{message}\n~~~"

COMMITS_COMMENT_MESSAGE_TEMPLATE = "{user_name} {action} on [{sha}]({url})"

PUSH_TAGS_MESSAGE_TEMPLATE = """{user_name} {action} tag {tag}"""
TAG_WITH_URL_TEMPLATE = "[{tag_name}]({tag_url})"
TAG_WITHOUT_URL_TEMPLATE = "{tag_name}"

RELEASE_MESSAGE_TEMPLATE = "{user_name} {action} release [{release_name}]({url}) for tag {tagname}."


def get_assignee_string(assignees: List[Dict[str, Any]]) -> str:
    assignees_string = ""
    if len(assignees) == 1:
        assignees_string = "{username}".format(**assignees[0])
    else:
        usernames = []
        for a in assignees:
            usernames.append(a["username"])

        assignees_string = ", ".join(usernames[:-1]) + " and " + usernames[-1]
    return assignees_string


def get_push_commits_event_message(
    user_name: str,
    compare_url: Optional[str],
    branch_name: str,
    commits_data: List[Dict[str, Any]],
    is_truncated: bool = False,
    deleted: bool = False,
    force_push: Optional[bool] = False,
) -> str:
    if not commits_data and deleted:
        return PUSH_DELETE_BRANCH_MESSAGE_TEMPLATE.format(
            user_name=user_name,
            compare_url=compare_url,
            branch_name=branch_name,
        )

    push_type = "force pushed" if force_push else "pushed"
    if not commits_data and not deleted:
        if compare_url:
            return PUSH_LOCAL_BRANCH_WITHOUT_COMMITS_MESSAGE_TEMPLATE.format(
                push_type=push_type,
                user_name=user_name,
                compare_url=compare_url,
                branch_name=branch_name,
            )
        return PUSH_LOCAL_BRANCH_WITHOUT_COMMITS_MESSAGE_WITHOUT_URL_TEMPLATE.format(
            push_type=push_type,
            user_name=user_name,
            branch_name=branch_name,
        )

    pushed_message_template = (
        PUSH_PUSHED_TEXT_WITH_URL if compare_url else PUSH_PUSHED_TEXT_WITHOUT_URL
    )

    pushed_text_message = pushed_message_template.format(
        push_type=push_type,
        compare_url=compare_url,
        number_of_commits=len(commits_data),
        commit_or_commits=COMMIT_OR_COMMITS.format("s" if len(commits_data) > 1 else ""),
    )

    committers_items: List[Tuple[str, int]] = get_all_committers(commits_data)
    if len(committers_items) == 1 and user_name == committers_items[0][0]:
        return PUSH_COMMITS_MESSAGE_TEMPLATE_WITHOUT_COMMITTERS.format(
            user_name=user_name,
            pushed_text=pushed_text_message,
            branch_name=branch_name,
            commits_data=get_commits_content(commits_data, is_truncated),
        ).rstrip()
    else:
        committers_details = "{} ({})".format(*committers_items[0])

        for name, number_of_commits in committers_items[1:-1]:
            committers_details = f"{committers_details}, {name} ({number_of_commits})"

        if len(committers_items) > 1:
            committers_details = "{} and {} ({})".format(committers_details, *committers_items[-1])

        return PUSH_COMMITS_MESSAGE_TEMPLATE_WITH_COMMITTERS.format(
            user_name=user_name,
            pushed_text=pushed_text_message,
            branch_name=branch_name,
            committers_details=PUSH_COMMITS_MESSAGE_EXTENSION.format(committers_details),
            commits_data=get_commits_content(commits_data, is_truncated),
        ).rstrip()


def get_force_push_commits_event_message(
    user_name: str, url: str, branch_name: str, head: str
) -> str:
    return FORCE_PUSH_COMMITS_MESSAGE_TEMPLATE.format(
        user_name=user_name,
        url=url,
        branch_name=branch_name,
        head=head,
    )


def get_create_branch_event_message(user_name: str, url: Optional[str], branch_name: str) -> str:
    if url is None:
        return CREATE_BRANCH_WITHOUT_URL_MESSAGE_TEMPLATE.format(
            user_name=user_name,
            branch_name=branch_name,
        )
    return CREATE_BRANCH_MESSAGE_TEMPLATE.format(
        user_name=user_name,
        url=url,
        branch_name=branch_name,
    )


def get_remove_branch_event_message(user_name: str, branch_name: str) -> str:
    return REMOVE_BRANCH_MESSAGE_TEMPLATE.format(
        user_name=user_name,
        branch_name=branch_name,
    )


def get_pull_request_event_message(
    *,
    user_name: str,
    action: str,
    url: str,
    number: Optional[int] = None,
    target_branch: Optional[str] = None,
    base_branch: Optional[str] = None,
    message: Optional[str] = None,
    assignee: Optional[str] = None,
    assignees: Optional[List[Dict[str, Any]]] = None,
    reviewer: Optional[str] = None,
    type: str = "PR",
    title: Optional[str] = None,
) -> str:
    kwargs = {
        "user_name": user_name,
        "action": action,
        "type": type,
        "url": url,
        "id": f" #{number}" if number is not None else "",
        "title": title,
    }

    if title is not None:
        main_message = PULL_REQUEST_OR_ISSUE_MESSAGE_TEMPLATE_WITH_TITLE.format(**kwargs)
    else:
        main_message = PULL_REQUEST_OR_ISSUE_MESSAGE_TEMPLATE.format(**kwargs)

    if target_branch and base_branch:
        branch_info = PULL_REQUEST_BRANCH_INFO_TEMPLATE.format(
            target=target_branch,
            base=base_branch,
        )
        main_message = f"{main_message} {branch_info}"

    if assignees:
        assignee_string = get_assignee_string(assignees)
        assignee_info = PULL_REQUEST_OR_ISSUE_ASSIGNEE_INFO_TEMPLATE.format(
            assignee=assignee_string
        )

    elif assignee:
        assignee_info = PULL_REQUEST_OR_ISSUE_ASSIGNEE_INFO_TEMPLATE.format(assignee=assignee)

    elif reviewer:
        assignee_info = PULL_REQUEST_REVIEWER_INFO_TEMPLATE.format(reviewer=reviewer)

    if assignees or assignee or reviewer:
        main_message = f"{main_message} {assignee_info}"

    punctuation = ":" if message else "."
    if (
        assignees
        or assignee
        or (target_branch and base_branch)
        or title is None
        # Once we get here, we know that the message ends with a title
        # which could already have punctuation at the end
        or title[-1] not in string.punctuation
    ):
        main_message = f"{main_message}{punctuation}"

    if message:
        main_message += "\n" + CONTENT_MESSAGE_TEMPLATE.format(message=message)
    return main_message.rstrip()


def get_issue_event_message(
    *,
    user_name: str,
    action: str,
    url: str,
    number: Optional[int] = None,
    message: Optional[str] = None,
    assignee: Optional[str] = None,
    assignees: Optional[List[Dict[str, Any]]] = None,
    title: Optional[str] = None,
) -> str:
    return get_pull_request_event_message(
        user_name=user_name,
        action=action,
        url=url,
        number=number,
        message=message,
        assignee=assignee,
        assignees=assignees,
        type="issue",
        title=title,
    )


def get_push_tag_event_message(
    user_name: str, tag_name: str, tag_url: Optional[str] = None, action: str = "pushed"
) -> str:
    if tag_url:
        tag_part = TAG_WITH_URL_TEMPLATE.format(tag_name=tag_name, tag_url=tag_url)
    else:
        tag_part = TAG_WITHOUT_URL_TEMPLATE.format(tag_name=tag_name)

    message = PUSH_TAGS_MESSAGE_TEMPLATE.format(
        user_name=user_name,
        action=action,
        tag=tag_part,
    )

    if tag_name[-1] not in string.punctuation:
        message = f"{message}."

    return message


def get_commits_comment_action_message(
    user_name: str, action: str, commit_url: str, sha: str, message: Optional[str] = None
) -> str:
    content = COMMITS_COMMENT_MESSAGE_TEMPLATE.format(
        user_name=user_name,
        action=action,
        sha=get_short_sha(sha),
        url=commit_url,
    )
    punctuation = ":" if message else "."
    content = f"{content}{punctuation}"
    if message:
        content += CONTENT_MESSAGE_TEMPLATE.format(
            message=message,
        )

    return content


def get_commits_content(commits_data: List[Dict[str, Any]], is_truncated: bool = False) -> str:
    commits_content = ""
    for commit in commits_data[:COMMITS_LIMIT]:
        commits_content += COMMIT_ROW_TEMPLATE.format(
            commit_short_sha=get_short_sha(commit["sha"]),
            commit_url=commit.get("url"),
            commit_msg=commit["message"].partition("\n")[0],
        )

    if len(commits_data) > COMMITS_LIMIT:
        commits_content += COMMITS_MORE_THAN_LIMIT_TEMPLATE.format(
            commits_number=len(commits_data) - COMMITS_LIMIT,
        )
    elif is_truncated:
        commits_content += COMMITS_MORE_THAN_LIMIT_TEMPLATE.format(
            commits_number="",
        ).replace("  ", " ")
    return commits_content.rstrip()


def get_release_event_message(
    user_name: str, action: str, tagname: str, release_name: str, url: str
) -> str:
    content = RELEASE_MESSAGE_TEMPLATE.format(
        user_name=user_name,
        action=action,
        tagname=tagname,
        release_name=release_name,
        url=url,
    )

    return content


def get_short_sha(sha: str) -> str:
    return sha[:11]


def get_all_committers(commits_data: List[Dict[str, Any]]) -> List[Tuple[str, int]]:
    committers: Dict[str, int] = defaultdict(int)

    for commit in commits_data:
        committers[commit["name"]] += 1

    # Sort by commit count, breaking ties alphabetically.
    committers_items: List[Tuple[str, int]] = sorted(
        committers.items(),
        key=lambda item: (-item[1], item[0]),
    )
    committers_values: List[int] = [c_i[1] for c_i in committers_items]

    if len(committers) > PUSH_COMMITTERS_LIMIT_INFO:
        others_number_of_commits = sum(committers_values[PUSH_COMMITTERS_LIMIT_INFO:])
        committers_items = committers_items[:PUSH_COMMITTERS_LIMIT_INFO]
        committers_items.append(("others", others_number_of_commits))

    return committers_items