"""Datenquellen anlegen, anzeigen und testen (→ Konzept 4.2, 5.5)."""

from sqlalchemy import select
from sqlalchemy.orm import Session

from app import audit
from app.core.config import Settings
from app.core.crypto import Vault
from app.core.database import now
from app.core.errors import Forbidden, Invalid, NotFound
from app.data_sources.connectors import TestResult
from app.data_sources.connectors.git import GitConnector, check_config, check_username
from app.data_sources.connectors.pull_requests import BITBUCKET_URL, PROVIDERS
from app.data_sources.models import DataSource
from app.identity import Principal
from app.uploads.service import has_tables
from app.workspaces import service as workspaces


def list_for(session: Session, principal: Principal, workspace_id: int) -> list[DataSource]:
    workspaces.get(session, principal, workspace_id)
    return list(session.scalars(select(DataSource).where(DataSource.workspace_id == workspace_id)
                                .order_by(DataSource.name)))


def get(session: Session, principal: Principal, source_id: int) -> DataSource:
    source = session.get(DataSource, source_id)
    if source is None:
        raise NotFound
    workspaces.get(session, principal, source.workspace_id)  # NotFound für Nichtmitglieder
    return source


def check_pr_provider(kind: str, url: str) -> str:
    if kind not in PROVIDERS:
        raise Invalid("Unbekannter Pull-Request-Anbieter.")
    if kind == "bitbucket_dc" and not BITBUCKET_URL.match(url):
        raise Invalid("Für Bitbucket Data Center muss die URL die Form https://host/scm/PROJEKT/repo.git haben.")
    return kind


def check_token(token: str) -> str:
    token = token.strip()
    if token and (len(token) < 8 or any(c.isspace() for c in token)):
        raise Invalid("Das sieht nicht nach einem Token aus.")
    return token


def create_git(session: Session, principal: Principal, settings: Settings, vault: Vault, workspace_id: int, *,
               name: str, url: str, branch: str, token: str, exposure_confirmed: bool,
               pr_provider: str = "none", delete_branches: bool = True, username: str = "") -> DataSource:
    workspaces.require_admin(session, principal, workspace_id)
    if not name.strip():
        raise Invalid("Name fehlt.")
    if not exposure_confirmed:
        raise Invalid("Bitte bestätigen, dass alle Mitglieder des Workspace diese Daten sehen dürfen.")
    config = check_config(url, branch, settings)
    token, username = check_token(token), check_username(username)
    if username and not token:
        raise Invalid("Der Nutzername gilt nur zusammen mit einem Token.")
    source = DataSource(workspace_id=workspace_id, kind="git", name=name.strip()[:200],
                        config={"url": config.url, "branch": config.branch,
                                "pr_provider": check_pr_provider(pr_provider, config.url),
                                "delete_branches": delete_branches, "username": username},
                        secret=vault.encrypt(token) if token else None, secret_hint=token[-4:] if token else "",
                        exposure_confirmed_by=principal.user_id, created_by=principal.user_id)
    session.add(source)
    session.flush()
    audit.record(session, "source.created", user_id=principal.user_id, workspace_id=workspace_id,
                 target_kind="source", target_id=source.id, kind="git", url=config.url, branch=config.branch,
                 token=bool(token), auth="basic" if username else "bearer")
    audit.record(session, "source.exposure_confirmed", user_id=principal.user_id, workspace_id=workspace_id,
                 target_kind="source", target_id=source.id)
    return source


def update_git(session: Session, principal: Principal, settings: Settings, vault: Vault, source_id: int, *,
               name: str, branch: str, token: str, remove_token: bool, pr_provider: str = "none",
               delete_branches: bool = True, username: str = "") -> DataSource:
    """Name, Branch und Token ändern. Die URL bleibt: eine andere URL ist eine neue Quelle
    mit neuer Bestätigung. Nach einer Änderung muss die Quelle neu getestet werden."""
    source = require_testable(session, principal, source_id)
    if source.kind != "git":
        raise Invalid("Das ist keine Git-Quelle.")
    if not name.strip():
        raise Invalid("Name fehlt.")
    config = check_config(source.config["url"], branch, settings)
    token, username = check_token(token), check_username(username)
    if username and not (token or (source.secret and not remove_token)):
        raise Invalid("Der Nutzername gilt nur zusammen mit einem Token.")
    changed = (config.branch != source.config["branch"] or bool(token) or (remove_token and source.secret)
               or username != source.config.get("username", ""))
    source.name = name.strip()[:200]
    source.config = {**source.config, "branch": config.branch,
                     "pr_provider": check_pr_provider(pr_provider, source.config["url"]),
                     "delete_branches": delete_branches, "username": username}
    if token:
        source.secret, source.secret_hint = vault.encrypt(token), token[-4:]
    elif remove_token:
        source.secret, source.secret_hint = None, ""
    if changed:
        source.status, source.status_message = "new", "Geändert, bitte neu testen."
    audit.record(session, "source.updated", user_id=principal.user_id, workspace_id=source.workspace_id,
                 target_kind="source", target_id=source.id, branch=config.branch,
                 token="ersetzt" if token else "entfernt" if remove_token else "unverändert",
                 auth="basic" if username else "bearer")
    return source


def delete(session: Session, principal: Principal, source_id: int) -> int:
    source = require_testable(session, principal, source_id)
    workspace_id = source.workspace_id
    audit.record(session, "source.deleted", user_id=principal.user_id, workspace_id=workspace_id,
                 target_kind="source", target_id=source.id, kind=source.kind,
                 target=source.config.get("url") or source.config.get("host", ""))
    session.delete(source)
    return workspace_id


def connector(source: DataSource, settings: Settings, vault: Vault) -> GitConnector:
    token = vault.decrypt(source.secret) if source.secret else None
    return GitConnector(check_config(source.config["url"], source.config["branch"], settings), settings, token,
                        source.config.get("username", ""))


def run_test(source: DataSource, settings: Settings, vault: Vault) -> TestResult:
    """Ohne offene Transaktion aufrufen: der Test kann bis zum Zeitlimit dauern."""
    try:
        return connector(source, settings, vault).test_connection()
    except Invalid as e:  # z. B. Host inzwischen nicht mehr freigegeben
        return TestResult(False, str(e))
    except RuntimeError as e:  # Token lässt sich nicht entschlüsseln (anderer AIW_SECRET_KEY)
        return TestResult(False, str(e))


def require_testable(session: Session, principal: Principal, source_id: int) -> DataSource:
    source = get(session, principal, source_id)
    if not workspaces.get(session, principal, source.workspace_id).is_admin:
        raise Forbidden
    return source


def save_test(session: Session, principal: Principal, source_id: int, result: TestResult) -> None:
    source = require_testable(session, principal, source_id)
    source.status = "ok" if result.ok else "error"
    source.status_message = result.message
    source.last_tested = now()
    audit.record(session, "source.tested", user_id=principal.user_id, workspace_id=source.workspace_id,
                 target_kind="source", target_id=source.id, ok=result.ok, message=result.message)


def chat_ready(session: Session, workspace_id: int) -> bool:
    """Context first (→ Konzept 1): Chat erst mit mindestens einer erfolgreich getesteten Quelle,
    einer erfolgreich eingelesenen Datei oder einem abgeglichenen Ordner."""
    from app.documents.models import DocFolder
    return session.scalar(select(DataSource.id).where(
        DataSource.workspace_id == workspace_id, DataSource.status == "ok").limit(1)) is not None \
        or has_tables(session, workspace_id) \
        or session.scalar(select(DocFolder.id).where(DocFolder.workspace_id == workspace_id).limit(1)) is not None