from __future__ import annotations

from review_agent.models import ApplicationFormFillBatch, ExportedSummaryFile, FileSummaryBatch, RegulatoryReviewBatch

from .permissions import can_access_batch


WORKFLOW_MODELS = {
    "file_summary": FileSummaryBatch,
    "regulatory_review": RegulatoryReviewBatch,
    "application_form_fill": ApplicationFormFillBatch,
}


def query_batch_summary(user, *, workflow_type: str | None = None, batch_no: str | None = None, latest: bool = False) -> dict:
    candidates = _candidate_batches(workflow_type)
    if batch_no:
        for current_workflow_type, model in candidates:
            batch = model.objects.filter(batch_no=batch_no).first()
            if batch:
                return _serialize_allowed_batch(user, current_workflow_type, batch)
        return {"ok": False, "permission_result": "not_found", "answer_summary": "未找到对应批次。"}

    if latest:
        for current_workflow_type, model in candidates:
            queryset = model.objects.all().order_by("-finished_at", "-created_at", "-id")
            for batch in queryset:
                if can_access_batch(user, batch):
                    return _serialize_batch(current_workflow_type, batch, permission_result="allowed")
        return {"ok": False, "permission_result": "not_found", "answer_summary": "未找到可访问的批次。"}

    return {"ok": False, "permission_result": "not_found", "answer_summary": "请提供批次号，或询问最新/最近批次。"}


def _candidate_batches(workflow_type: str | None):
    if workflow_type and workflow_type in WORKFLOW_MODELS:
        return [(workflow_type, WORKFLOW_MODELS[workflow_type])]
    return list(WORKFLOW_MODELS.items())


def _serialize_allowed_batch(user, workflow_type: str, batch) -> dict:
    if not can_access_batch(user, batch):
        return {"ok": False, "permission_result": "denied", "answer_summary": "无权限访问该批次。"}
    return _serialize_batch(workflow_type, batch, permission_result="allowed")


def _serialize_batch(workflow_type: str, batch, *, permission_result: str) -> dict:
    summary = _summary_for_batch(workflow_type, batch)
    result_url = _result_url(workflow_type, batch.pk)
    answer = f"{batch.batch_no} 状态 {batch.status}。{summary}"
    return {
        "ok": True,
        "permission_result": permission_result,
        "workflow_type": workflow_type,
        "batch_id": batch.pk,
        "batch_no": batch.batch_no,
        "status": batch.status,
        "summary": summary,
        "result_url": result_url,
        "answer_summary": answer,
    }


def _summary_for_batch(workflow_type: str, batch) -> str:
    if workflow_type == "file_summary":
        return f"文件 {batch.total_files} 个，成功 {batch.success_files} 个，失败 {batch.failed_files} 个。"
    if workflow_type == "regulatory_review":
        risk = batch.risk_summary or {}
        return f"阻断项 {int(risk.get('blocking') or 0)} 个，高风险 {int(risk.get('high') or 0)} 个。"
    if workflow_type == "application_form_fill":
        export_count = ExportedSummaryFile.objects.filter(
            workflow_type="application_form_fill",
            workflow_batch_id=batch.pk,
        ).count()
        return f"导出文件 {export_count} 个，冲突字段 {len(batch.conflict_summary or [])} 个。"
    return ""


def _result_url(workflow_type: str, batch_id: int) -> str:
    paths = {
        "file_summary": f"/api/review-agent/file-summary/{batch_id}/status/",
        "regulatory_review": f"/api/review-agent/regulatory-review/{batch_id}/status/",
        "application_form_fill": f"/api/review-agent/application-form-fill/{batch_id}/status/",
    }
    return paths.get(workflow_type, "/")