from __future__ import annotations

from fastapi import APIRouter, Request
from fastapi.responses import RedirectResponse

from app.core.db.common import CommonSessionLocal
from app.core.templating import templates
from app.modules.accounting.master_integrity_service import build_master_integrity_report, filter_integrity_issues
from app.modules.accounting.ui import _require_partner, _visible_clients
from app.modules.core.rbac.deps import get_user_permissions, get_user_roles

router = APIRouter(
    prefix="/tools/accounting/master-integrity",
    tags=["accounting-master-integrity-ui"],
)


@router.get("")
def page(
    request: Request,
    client_id: int | None = None,
    tally_guid: str = "",
    q: str = "",
    severity: str = "",
    master_type: str = "",
    issue_type: str = "",
    page: int = 1,
    per_page: int = 50,
):
    db = CommonSessionLocal()
    try:
        user, denied = _require_partner(request, db, "accounting.tally.view")
        if denied:
            return denied

        clients, scope = _visible_clients(db, request, user)
        selected = next((c for c in clients if client_id and int(c.id) == int(client_id)), None)

        # This phase intentionally analyzes the already-synced ERP master snapshots.
        # Tally writes are not performed from this report.
        report = {
            "summary": {"groups": 0, "ledgers": 0, "stock_groups": 0, "stock_items": 0, "units": 0,
                        "issues": 0, "high": 0, "medium": 0, "low": 0},
            "issues": [], "issue_types": [], "master_types": [],
        }
        filtered = {"rows": [], "total": 0, "page": 1, "pages": 1, "per_page": per_page}
        available_guids = []

        if selected:
            from sqlalchemy import select
            from app.modules.accounting.chart_models import AccountingChartLedger
            available_guids = [
                row[0] for row in db.execute(
                    select(AccountingChartLedger.tally_guid)
                    .where(
                        AccountingChartLedger.tenant_id == scope.tenant_id,
                        AccountingChartLedger.client_id == selected.id,
                    )
                    .distinct()
                    .order_by(AccountingChartLedger.tally_guid)
                ).all()
                if str(row[0] or "").strip()
            ]
            if tally_guid and tally_guid not in available_guids:
                tally_guid = ""
            if not tally_guid and len(available_guids) == 1:
                tally_guid = available_guids[0]

            if tally_guid:
                report = build_master_integrity_report(
                    db,
                    tenant_id=scope.tenant_id,
                    client_id=selected.id,
                    tally_guid=tally_guid,
                )
                filtered = filter_integrity_issues(
                    report, q=q, severity=severity, master_type=master_type,
                    issue_type=issue_type, page=page, per_page=per_page,
                )

        return templates.TemplateResponse(
            "modules/accounting/templates/accounting/master_integrity.html",
            {
                "request": request,
                "current_user": user,
                "current_user_roles": get_user_roles(db, user.id),
                "current_user_permissions": get_user_permissions(db, user.id),
                "title": "Master Integrity Engine",
                "clients": clients,
                "selected_client": selected,
                "available_guids": available_guids,
                "selected_tally_guid": tally_guid,
                "report": report,
                "filtered": filtered,
                "q": q,
                "severity_filter": severity,
                "master_type_filter": master_type,
                "issue_type_filter": issue_type,
            },
        )
    finally:
        db.close()