from __future__ import annotations

from uuid import uuid4

from app.agents.schemas.orchestration import ParallelWorthiness, TaskGraph, TaskNode


ROLE_KEYWORDS: list[tuple[str, tuple[str, ...]]] = [
    ("librarian", ("查", "检索", "资料", "文档", "知识库", "年报", "forum", "search")),
    ("analyst", ("分析", "判断", "风险", "总结", "对比", "洞察", "结论")),
    ("schedule_planner", ("计划", "安排", "下周", "日程", "提醒", "优先级")),
    ("executor", ("执行", "创建", "更新", "落库", "提交", "发帖")),
]


def build_bounded_task_graph(
    *,
    query_text: str,
    parallel_worthiness: ParallelWorthiness,
    max_nodes: int = 4,
) -> TaskGraph | None:
    roles = _infer_roles(query_text)
    if not roles:
        return None

    independent_roles = roles[: min(max_nodes - 1, max(1, parallel_worthiness.estimated_subtasks))]
    nodes: list[TaskNode] = []

    for index, role in enumerate(independent_roles, start=1):
        node_id = f"task-{index}-{uuid4().hex[:6]}"
        nodes.append(
            TaskNode(
                node_id=node_id,
                title=_build_title(role),
                role=role,
                goal=_build_goal(role, query_text),
                depends_on=[],
                execution_mode=(
                    "parallel"
                    if parallel_worthiness.preferred_mode in {"collaboration", "parallel"}
                    and len(independent_roles) > 1
                    else "serial"
                ),
                expected_evidence=_build_expected_evidence(role),
            )
        )

    if len(nodes) > 1:
        merge_id = f"merge-{uuid4().hex[:6]}"
        nodes.append(
            TaskNode(
                node_id=merge_id,
                title="汇总并收敛最终结论",
                role="master",
                goal="汇总前置子任务结果，形成统一可验证的输出。",
                depends_on=[node.node_id for node in nodes],
                execution_mode="serial",
                expected_evidence=[{"type": "merge", "detail": "merged summary and conflict notes"}],
            )
        )

    return TaskGraph(
        nodes=nodes,
        entry_node_ids=[node.node_id for node in nodes if not node.depends_on],
        max_parallelism=max(1, len(independent_roles)),
        rationale=_build_rationale(parallel_worthiness, independent_roles),
    )


def render_task_graph_summary(task_graph: TaskGraph | None) -> str | None:
    if task_graph is None or not task_graph.nodes:
        return None

    lines = ["- 任务图:"]
    for node in task_graph.nodes[:4]:
        deps = f" deps={','.join(node.depends_on)}" if node.depends_on else ""
        lines.append(f"  - [{node.execution_mode}] {node.title} ({node.role}){deps}")
    return "\n".join(lines)


def _infer_roles(query_text: str) -> list[str]:
    selected: list[str] = []
    text = query_text or ""
    for role, keywords in ROLE_KEYWORDS:
        if any(keyword in text for keyword in keywords):
            selected.append(role)

    if not selected:
        return ["analyst"]
    return selected


def _build_title(role: str) -> str:
    mapping = {
        "librarian": "收集事实与外部/内部证据",
        "analyst": "形成判断与风险分析",
        "schedule_planner": "整理计划和优先级",
        "executor": "执行必要操作并回收结果",
    }
    return mapping.get(role, "处理子任务")


def _build_goal(role: str, query_text: str) -> str:
    mapping = {
        "librarian": f"围绕请求收集支持结论的事实和资料：{query_text}",
        "analyst": f"基于当前请求输出结构化判断：{query_text}",
        "schedule_planner": f"把当前请求收束为计划、安排或优先级：{query_text}",
        "executor": f"基于请求执行必要动作并返回结果：{query_text}",
    }
    return mapping.get(role, query_text)


def _build_expected_evidence(role: str) -> list[dict[str, str]]:
    mapping = {
        "librarian": [{"type": "evidence", "detail": "retrieval findings"}],
        "analyst": [{"type": "analysis", "detail": "structured judgment"}],
        "schedule_planner": [{"type": "plan", "detail": "explicit schedule or priorities"}],
        "executor": [{"type": "execution", "detail": "tool output or mutation result"}],
    }
    return mapping.get(role, [{"type": "summary", "detail": "task summary"}])


def _build_rationale(parallel_worthiness: ParallelWorthiness, roles: list[str]) -> str:
    return (
        f"preferred_mode={parallel_worthiness.preferred_mode}; "
        f"score={parallel_worthiness.score:.2f}; "
        f"roles={','.join(roles)}"
    )