import { nanoid } from "nanoid";

import { getNodeSpec } from "../constants";
import { CanvasNodeType, type CanvasConnection, type CanvasNodeData, type CanvasNodeMetadata, type ViewportTransform } from "../types";

export type CanvasAgentOp =
    | { type: "add_node"; id?: string; nodeType?: CanvasNodeType; title?: string; position?: { x: number; y: number }; x?: number; y?: number; width?: number; height?: number; metadata?: CanvasNodeMetadata }
    | { type: "update_node"; id: string; patch?: Partial<CanvasNodeData>; metadata?: CanvasNodeMetadata }
    | { type: "delete_node"; id?: string; ids?: string[] }
    | { type: "connect_nodes"; id?: string; fromNodeId: string; toNodeId: string }
    | { type: "set_viewport"; viewport: ViewportTransform }
    | { type: "select_nodes"; ids: string[] }
    | { type: "run_generation"; nodeId: string; mode?: "text" | "image" | "video" | "audio"; prompt?: string };

export type CanvasAgentSnapshot = {
    projectId: string;
    title: string;
    nodes: CanvasNodeData[];
    connections: CanvasConnection[];
    selectedNodeIds: string[];
    viewport: ViewportTransform;
};

export function summarizeCanvasAgentOps(ops: CanvasAgentOp[]) {
    const counts = ops.reduce<Record<string, number>>((acc, op) => {
        acc[op.type] = (acc[op.type] || 0) + 1;
        return acc;
    }, {});
    return Object.entries(counts)
        .map(([type, count]) => `${opLabel(type)} ${count}`)
        .join("，");
}

export function applyCanvasAgentOps(snapshot: CanvasAgentSnapshot, ops: CanvasAgentOp[]) {
    let nodes = snapshot.nodes;
    let connections = snapshot.connections;
    let selectedNodeIds = snapshot.selectedNodeIds;
    let viewport = snapshot.viewport;

    ops.forEach((op, index) => {
        if (op.type === "add_node") {
            const nodeType = op.nodeType || CanvasNodeType.Text;
            const spec = getNodeSpec(nodeType);
            const node: CanvasNodeData = {
                id: op.id || `${nodeType}-${Date.now()}-${index}`,
                type: nodeType,
                title: op.title || spec.title,
                position: op.position || { x: op.x ?? index * 36, y: op.y ?? index * 36 },
                width: op.width || spec.width,
                height: op.height || spec.height,
                metadata: { ...spec.metadata, ...op.metadata },
            };
            nodes = [...nodes, node];
            selectedNodeIds = [node.id];
        }
        if (op.type === "update_node") {
            nodes = nodes.map((node) => (node.id === op.id ? { ...node, ...op.patch, metadata: { ...node.metadata, ...op.patch?.metadata, ...op.metadata } } : node));
        }
        if (op.type === "delete_node") {
            const ids = new Set(op.ids || (op.id ? [op.id] : []));
            nodes = nodes.filter((node) => !ids.has(node.id));
            connections = connections.filter((conn) => !ids.has(conn.fromNodeId) && !ids.has(conn.toNodeId));
            selectedNodeIds = selectedNodeIds.filter((id) => !ids.has(id));
        }
        if (op.type === "connect_nodes") {
            const exists = connections.some((conn) => conn.fromNodeId === op.fromNodeId && conn.toNodeId === op.toNodeId);
            const hasNodes = nodes.some((node) => node.id === op.fromNodeId) && nodes.some((node) => node.id === op.toNodeId);
            if (!exists && hasNodes) connections = [...connections, { id: op.id || nanoid(), fromNodeId: op.fromNodeId, toNodeId: op.toNodeId }];
        }
        if (op.type === "set_viewport") viewport = op.viewport;
        if (op.type === "select_nodes") selectedNodeIds = op.ids.filter((id) => nodes.some((node) => node.id === id));
    });

    return { ...snapshot, nodes, connections, selectedNodeIds, viewport };
}

function opLabel(type: string) {
    if (type === "add_node") return "新增节点";
    if (type === "update_node") return "更新节点";
    if (type === "delete_node") return "删除节点";
    if (type === "connect_nodes") return "连接";
    if (type === "set_viewport") return "调整视图";
    if (type === "select_nodes") return "选择节点";
    if (type === "run_generation") return "触发生成";
    return type;
}