"""Tasks plugin routes — CRUD, assign, status update."""

from __future__ import annotations

import uuid

from fastapi import APIRouter, Depends, HTTPException, Query, Response, status
from sqlalchemy.ext.asyncio import AsyncSession

from app.core.db import get_db
from app.deps import get_current_user, require_permission
from app.plugins.builtins.tasks import services
from app.plugins.builtins.tasks.schemas import (
    TaskAssignRequest,
    TaskCreate,
    TaskStatusRequest,
    TaskUpdate,
)

router = APIRouter(prefix="/api/v1/tasks", tags=["tasks"])


def _parse_uuid(val: str, field: str) -> uuid.UUID:
    try:
        return uuid.UUID(val)
    except (ValueError, TypeError):
        raise HTTPException(
            400, detail={"detail": f"Invalid {field}", "code": "invalid_id"}
        ) from None


@router.get("", dependencies=[Depends(require_permission("tasks:read"))])
async def list_tasks(
    page: int = Query(1, ge=1),
    page_size: int = Query(25, ge=1, le=100),
    status: str | None = Query(None, pattern="^(open|in_progress|done)$"),
    priority: str | None = Query(None, pattern="^(low|medium|high|urgent)$"),
    assigned_to: str | None = Query(None),
    contact_id: str | None = Query(None),
    search: str | None = Query(None),
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """List tasks with filtering and pagination."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    return await services.list_tasks(
        db, tenant_id,
        page=page, page_size=page_size,
        status=status, priority=priority,
        assigned_to=assigned_to, contact_id=contact_id,
        search=search,
    )


@router.post("", status_code=status.HTTP_201_CREATED, dependencies=[Depends(require_permission("tasks:write"))])
async def create_task(
    body: TaskCreate,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """Create a new task."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    user_id = uuid.UUID(current_user["user_id"])
    data = body.model_dump()
    return await services.create_task(db, tenant_id, user_id, data)


@router.get("/{task_id}", dependencies=[Depends(require_permission("tasks:read"))])
async def get_task(
    task_id: str,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """Get a single task by ID."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    tid = _parse_uuid(task_id, "task_id")
    result = await services.get_task(db, tenant_id, tid)
    if result is None:
        raise HTTPException(404, detail={"detail": "Task not found", "code": "not_found"})
    return result


@router.patch("/{task_id}", dependencies=[Depends(require_permission("tasks:write"))])
async def update_task(
    task_id: str,
    body: TaskUpdate,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """Update a task."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    tid = _parse_uuid(task_id, "task_id")
    data = body.model_dump(exclude_unset=True)
    result = await services.update_task(db, tenant_id, tid, data)
    if result is None:
        raise HTTPException(404, detail={"detail": "Task not found", "code": "not_found"})
    return result


@router.delete("/{task_id}", status_code=status.HTTP_204_NO_CONTENT, dependencies=[Depends(require_permission("tasks:delete"))])
async def delete_task(
    task_id: str,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """Delete a task (soft-delete)."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    tid = _parse_uuid(task_id, "task_id")
    deleted = await services.delete_task(db, tenant_id, tid)
    if not deleted:
        raise HTTPException(404, detail={"detail": "Task not found", "code": "not_found"})
    return Response(status_code=status.HTTP_204_NO_CONTENT)


@router.post("/{task_id}/assign", dependencies=[Depends(require_permission("tasks:write"))])
async def assign_task(
    task_id: str,
    body: TaskAssignRequest,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """Assign a task to a user."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    tid = _parse_uuid(task_id, "task_id")
    assigned_to = _parse_uuid(body.assigned_to, "assigned_to")
    result = await services.assign_task(db, tenant_id, tid, assigned_to)
    if result is None:
        raise HTTPException(404, detail={"detail": "Task not found", "code": "not_found"})
    return result


@router.post("/{task_id}/status", dependencies=[Depends(require_permission("tasks:write"))])
async def update_task_status(
    task_id: str,
    body: TaskStatusRequest,
    db: AsyncSession = Depends(get_db),
    current_user: dict = Depends(get_current_user),
):
    """Update task status."""
    tenant_id = uuid.UUID(current_user["tenant_id"])
    tid = _parse_uuid(task_id, "task_id")
    result = await services.update_task_status(db, tenant_id, tid, body.status)
    if result is None:
        raise HTTPException(404, detail={"detail": "Task not found", "code": "not_found"})
    return result