"""GraphWorkflow explicit DAG builder."""

from __future__ import annotations

from typing import Any, Iterable

from beaver.coordinator.models import ExecutionGraph

from .base import (
    WorkflowAgentSpec,
    build_graph_from_dependencies,
    edges_to_dependencies,
    parse_agents,
    validate_output_agent,
)

WORKFLOW_NAME = "GraphWorkflow"


def build_graph(
    *,
    task: str,
    agents: Iterable[WorkflowAgentSpec | dict[str, Any]],
    edges: Iterable[tuple[str, str] | list[str]],
    output_agent: str,
    allow_disconnected: bool = False,
) -> ExecutionGraph:
    del task
    parsed = parse_agents(agents)
    edge_list = list(edges or [])
    if not edge_list:
        raise ValueError("GraphWorkflow requires edges")
    dependencies = edges_to_dependencies(agents=parsed, edges=edge_list)
    validate_output_agent(
        agents=parsed,
        dependencies=dependencies,
        output_agent=str(output_agent or "").strip(),
        allow_disconnected=allow_disconnected,
    )
    return build_graph_from_dependencies(
        workflow_name=WORKFLOW_NAME,
        strategy="dag",
        agents=parsed,
        dependencies=dependencies,
    )