from typing import Dict, Iterable, List, Set, Tuple

from github_client import GitHubClient, GitHubError
from issues import issue_key, matching_candidates
from model import Issue, Occurrence, RemoteIssue


GroupedOccurrences = Dict[Tuple[str, str, str], List[Occurrence]]


def _snapshot(client: GitHubClient, remote: RemoteIssue, include_comments: bool) -> Issue:
    comments = tuple(comment.body or "" for comment in client.comments(remote.number)) if include_comments else ()
    return Issue(remote.number, remote.state, remote.body or "", comments, remote.closed_at, remote.labels)


def snapshots(client: GitHubClient, comment_numbers: Iterable[int] = ()) -> List[Issue]:
    comment_numbers = set(comment_numbers)
    return [_snapshot(client, remote, remote.number in comment_numbers) for remote in client.issues()]


def _complete_snapshots(client: GitHubClient, grouped: GroupedOccurrences) -> List[Issue]:
    issue_list = snapshots(client)
    comment_numbers: Set[int] = set()
    for (branch, classname, testcase_name), occurrences in grouped.items():
        latest = occurrences[-1]
        comment_numbers.update(issue.number for issue in matching_candidates(latest.repository, branch, classname, testcase_name, issue_list))
    if not comment_numbers:
        return issue_list
    comments = {number: tuple(comment.body or "" for comment in client.comments(number)) for number in comment_numbers}
    return [Issue(issue.number, issue.state, issue.body, comments.get(issue.number, ()), issue.closed_at, issue.labels) for issue in issue_list]


def lookup_issue_candidates(client: GitHubClient, grouped: GroupedOccurrences) -> List[Issue]:
    candidates: Dict[int, Issue] = {}
    try:
        for (branch, classname, testcase_name), occurrences in grouped.items():
            latest = occurrences[-1]
            number = client.search_issue(issue_key(latest.repository, branch, classname, testcase_name))
            if number is None:
                return _complete_snapshots(client, grouped)
            remote = client.issue(number)
            candidate = _snapshot(client, remote, False)
            if remote.is_pull_request or len(matching_candidates(latest.repository, branch, classname, testcase_name, (candidate,))) != 1:
                return _complete_snapshots(client, grouped)
            candidates[candidate.number] = candidate
    except GitHubError:
        return _complete_snapshots(client, grouped)
    return [Issue(candidate.number, candidate.state, candidate.body, tuple(comment.body or "" for comment in client.comments(candidate.number)), candidate.closed_at, candidate.labels) for candidate in candidates.values()]