from __future__ import annotations

from datetime import datetime, timezone

from app.modules.documents.models import ERPAgentJob, ERPWorkstationAgent


def _utcnow():
    return datetime.now(timezone.utc)


def _iso(value):
    return value.isoformat() if value else None


def _elapsed_seconds(started):
    if not started:
        return 0
    try:
        now = _utcnow()
        value = started
        if value.tzinfo is None:
            value = value.replace(tzinfo=timezone.utc)
        return max(0, int((now - value).total_seconds()))
    except Exception:
        return 0


def historical_run_status(db, run):
    job = db.get(ERPAgentJob, run.agent_job_id) if run and run.agent_job_id else None
    workstation = db.get(ERPWorkstationAgent, run.workstation_agent_id) if run and run.workstation_agent_id else None

    job_status = str(job.status if job else run.status or "queued").lower()
    run_status = str(run.status or job_status).lower()

    if run_status == "completed":
        stage = "completed"
        label = "Completed"
        terminal = True
        ok = True
    elif run_status == "failed":
        stage = "failed"
        label = "Failed"
        terminal = True
        ok = False
    elif job_status == "claimed":
        stage = "processing"
        label = "Processing on workstation"
        terminal = False
        ok = None
    elif job_status == "succeeded":
        stage = "ingesting"
        label = "Result received; updating ERP evidence"
        terminal = False
        ok = None
    elif job_status == "failed":
        stage = "failed"
        label = "Failed"
        terminal = True
        ok = False
    elif job_status == "cancelled":
        stage = "failed"
        label = "Cancelled"
        terminal = True
        ok = False
    else:
        stage = "queued"
        label = "Queued for workstation"
        terminal = False
        ok = None

    return {
        "run_id": int(run.id),
        "job_id": int(job.id) if job else None,
        "status": run_status,
        "job_status": job_status,
        "stage": stage,
        "label": label,
        "terminal": terminal,
        "ok": ok,
        "workstation": (
            str(getattr(workstation, "machine_name", "") or "").strip()
            or str(getattr(workstation, "agent_instance_id", "") or "").strip()
            or "ERP Local Agent"
        ) if workstation else "ERP Local Agent",
        "company_name": str(run.company_name or run.tally_guid or ""),
        "date_from": str(run.date_from or ""),
        "date_to": str(run.date_to or ""),
        "evidence_rows": int(run.evidence_rows or 0),
        "attempts": int(job.attempts or 0) if job else 0,
        "max_attempts": int(job.max_attempts or 0) if job else 0,
        "error": str(run.error_message or (job.last_error if job else "") or ""),
        "created_at": _iso(run.created_at_utc),
        "claimed_at": _iso(job.claimed_at_utc) if job else None,
        "completed_at": _iso(run.completed_at_utc or (job.completed_at_utc if job else None)),
        "elapsed_seconds": _elapsed_seconds(run.created_at_utc),
    }