from __future__ import annotations

from datetime import datetime, timezone
from typing import Optional

from sqlmodel import Field, SQLModel


def _now() -> datetime:
    return datetime.now(timezone.utc)


#: How to reach a private repository. "token" is an HTTPS username + personal
#: access token; "ssh" is a private key.
AUTH_TYPES = ["none", "token", "ssh"]


class GitSource(SQLModel, table=True):
    """A Git repository that a stack's files are deployed from.

    The repository is the source of truth: a sync overwrites the stack's files
    with what the repo says, which is the whole point of GitOps and also the
    thing to be careful about. Only files the repo has ever provided are touched
    — see ``services/git_service.py`` — so the data directories compose creates
    inside a stack folder are never at risk.
    """

    id: Optional[int] = Field(default=None, primary_key=True)
    stack_id: str = Field(index=True, unique=True)
    url: str
    branch: str = "main"
    #: Subdirectory inside the repository holding the compose file. Empty means
    #: the repository root, which is the common case for one-stack repos.
    subdir: str = ""
    auth_type: str = "none"
    username: Optional[str] = None
    #: Encrypted: the access token, or the SSH private key.
    secret: Optional[str] = None
    #: Run `compose up -d` after a sync that actually changed something.
    auto_deploy: bool = True
    #: Poll the repository this often. None means only manual syncs and webhooks.
    poll_interval_minutes: Optional[int] = None
    #: Shared secret for the webhook endpoint (HMAC, or GitLab's token header).
    webhook_secret: str = ""
    #: JSON list of the paths the last sync wrote, relative to the stack folder.
    #: The only files a later sync is allowed to delete.
    managed_files: str = "[]"
    last_commit: Optional[str] = None
    last_synced_at: Optional[datetime] = None
    last_error: Optional[str] = None
    created_at: datetime = Field(default_factory=_now)
    updated_at: datetime = Field(default_factory=_now)


# --- API schemas ---


class GitSourceWrite(SQLModel):
    url: str
    branch: str = "main"
    subdir: str = ""
    auth_type: str = "none"
    username: Optional[str] = None
    #: Omitted on update keeps the stored one.
    secret: Optional[str] = None
    auto_deploy: bool = True
    poll_interval_minutes: Optional[int] = None


class GitSourceRead(SQLModel):
    stack_id: str
    url: str
    branch: str
    subdir: str
    auth_type: str
    username: Optional[str]
    has_secret: bool
    auto_deploy: bool
    poll_interval_minutes: Optional[int]
    webhook_url: str
    last_commit: Optional[str]
    last_synced_at: Optional[datetime]
    last_error: Optional[str]
    managed_file_count: int


class SyncResult(SQLModel):
    changed: bool
    commit: Optional[str] = None
    written: list[str] = []
    removed: list[str] = []
    deployed: bool = False
    detail: Optional[str] = None