/**
 * 工作流节点共享工具
 *
 * 提取自 WorkflowList.vue 与 WorkflowEditor.vue 中重复的节点配置：
 * - 颜色映射、类型标签、默认数据
 * - parseNodes / thumbnail 渲染辅助
 */

// ========== 节点类型颜色映射 ==========
export const nodeTypeColors = {
  userInput:   '#10B981',
  llm:         '#8B5CF6',
  skill:       '#06B6D4',
  agent:       '#F59E0B',
  smartAction: '#EC4899',
  condition:   '#F97316',
  output:      '#EF4444',
}

// ========== 节点类型中文标签 ==========
export const nodeTypeLabels = {
  userInput:   '用户输入',
  llm:         '大模型处理',
  skill:       '技能',
  agent:       '智能体',
  smartAction: '智能操作',
  condition:   '条件分支',
  output:      '输出',
}

/**
 * 解析 graphData（字符串或对象）为节点摘要数组
 * @param {string|object} graphData
 * @returns {Array<{type:string, color:string, label:string}>}
 */
export function parseNodes(graphData) {
  if (!graphData) return []
  try {
    const data = typeof graphData === 'string' ? JSON.parse(graphData) : graphData
    return (data.nodes || []).map(n => ({
      type: n.type,
      color: nodeTypeColors[n.type] || '#64748B',
      label: n.data?.label || n.label || n.type,
    }))
  } catch {
    return []
  }
}

/**
 * 解析 graphData 为带位置信息的图形结构（用于缩略图渲染）
 *
 * 返回的 nodes 中 rx/ry 为相对坐标 [0,1]：
 *   - 单点或共线时自动居中（避免除零与压扁）
 *   - 由调用方（如 NodeThumbnail）映射到具体 SVG 视口
 *
 * @param {string|object} graphData
 * @returns {{
 *   hasContent: boolean,
 *   nodes: Array<{id:string, type:string, color:string, label:string, rx:number, ry:number}>,
 *   edges: Array<{source:object, target:object}>
 * }}
 */
export function parseGraph(graphData) {
  if (!graphData) return { hasContent: false, nodes: [], edges: [] }
  try {
    const data = typeof graphData === 'string' ? JSON.parse(graphData) : graphData
    const rawNodes = data.nodes || []
    const rawEdges = data.edges || []
    if (!rawNodes.length) return { hasContent: false, nodes: [], edges: [] }

    const xs = rawNodes.map(n => n.position?.x ?? 0)
    const ys = rawNodes.map(n => n.position?.y ?? 0)
    const minX = Math.min(...xs), maxX = Math.max(...xs)
    const minY = Math.min(...ys), maxY = Math.max(...ys)
    const spanX = maxX - minX
    const spanY = maxY - minY

    const nodes = rawNodes.map(n => {
      const nx = n.position?.x ?? 0
      const ny = n.position?.y ?? 0
      return {
        id: String(n.id ?? ''),
        type: n.type,
        color: nodeTypeColors[n.type] || '#64748B',
        label: n.data?.label || n.label || n.type,
        rx: spanX > 0 ? (nx - minX) / spanX : 0.5,
        ry: spanY > 0 ? (ny - minY) / spanY : 0.5,
      }
    })

    const nodeMap = new Map(nodes.map(n => [n.id, n]))
    const edges = (rawEdges || [])
      .map(e => ({
        source: nodeMap.get(String(e.source)),
        target: nodeMap.get(String(e.target)),
      }))
      .filter(e => e.source && e.target)

    return { hasContent: true, nodes, edges }
  } catch {
    return { hasContent: false, nodes: [], edges: [] }
  }
}

/**
 * 根据节点类型返回默认 data 字段（与 WorkflowEditor.getDefaultData 保持一致）
 */
export function getDefaultData(type) {
  switch (type) {
    case 'userInput':
      return { label: '用户输入', variables: [] }
    case 'llm':
      return {
        label: '大模型处理',
        modelId: null,
        systemPrompt: '',
        userPrompt: '',
        inputs: [],
        outputs: [{ name: 'result', label: 'LLM 输出', type: 'string', description: '', required: false }],
        failStrategy: 'abort',
      }
    case 'agent':
      return { label: '智能体', agentId: '', agentName: '', modelId: null, failStrategy: 'abort' }
    case 'skill':
      return { label: '技能', skillId: '', skillName: '', modelId: null, failStrategy: 'abort' }
    case 'smartAction':
      return {
        label: '智能操作',
        actionPrompt: '',
        modelId: null,
        inputs: [],
        outputs: [{ name: 'result', label: '操作结果', type: 'string', description: '', required: false }],
        failStrategy: 'abort',
      }
    case 'condition':
      return { label: '条件分支', conditions: [{ type: 'IF', expression: '' }] }
    case 'output':
      return { label: '输出', fields: [{ name: 'result', label: '输出结果', type: 'string', description: '', required: false }] }
    default:
      return { label: '节点' }
  }
}