import * as vscode from 'vscode'
import * as prettier from 'prettier'
import { ERROR_KIND } from '../consts'
import { FormatErr } from '../type'

// 需要增强的种类,比如目前三元运算符 需要处理 省略 ？ 的场景
interface EnhancerKind {
  ternary?: boolean
  object?: boolean
}

export class Formatter {
  private dataPointMatcher = /\{\{(.*?)\}\}/g
  private eventBinderMatcher = /:([a-z][a-zA-Z0-9]*)="(.*?)"/g
  private logicNodeCondMatcher = /(If|Elif) cond="(.*?)"/
  private timerCache = 0
  /**
   * 逐行遍历文件,调用prettier引擎进行格式化
   * @param document vscode.TextDocument
   * @param edit vscode.TextEditorEdit
   */
  public handleCommand(document: vscode.TextDocument, edit: vscode.TextEditorEdit) {
    const now = Date.now()
    if (now - this.timerCache > 1000) {
      this.timerCache = now
    } else {
      return
    }
    let i = 0
    while (i < document.lineCount) {
      const textLine = document.lineAt(i)
      if (!textLine.isEmptyOrWhitespace) {
        const text = textLine.text
        // 对{{ }}中的内容进行格式化
        text.replace(this.dataPointMatcher, (_, p: string, index: number) => {
          const range = this.getRange(i, index, i, index + p.length + 4)
          try {
            const res = this.parse(p, { ternary: true })
            const str = `{{${res}}}`
            if (this.getText(document, range) !== str) {
              edit.replace(range, `{{${res}}}`)
            }
          } catch (error) {
            const err: FormatErr = { range, error, kind: ERROR_KIND.DATA_POINT }
            throw err
          }
          return ''
        })
        // 对binder中的({ })进行格式化
        text.replace(this.eventBinderMatcher, (_, p1: string, p2: string, index: number) => {
          const start = index + p1.length + 3
          const end = start + p2.length
          const range = this.getRange(i, start, i, end)
          try {
            const res = this.parse(p2, { object: true })
            if (this.getText(document, range) !== res) {
              edit.replace(range, res)
            }
          } catch (error) {
            const err: FormatErr = { range, error, kind: ERROR_KIND.EVENT_BINDER }
            throw err
          }
          return ''
        })
        // 对cond进行格式化
        text.replace(this.logicNodeCondMatcher, (_, p1: string, p2: string, index) => {
          const start = index + p1.length + 7
          const end = start + p2.length
          const range = this.getRange(i, start, i, end)
          try {
            const res = this.parse(p2, {})
            if (this.getText(document, range) !== res.trim()) {
              edit.replace(range, res.trim())
            }
          } catch (error) {
            const err: FormatErr = { range, error, kind: ERROR_KIND.COND }
            throw err
          }
          return ''
        })
      }
      i++
    }
  }
  private getPosition(y: number, x: number) {
    return new vscode.Position(y, x)
  }
  private getRange(y1: number, x1: number, y2: number, x2: number) {
    const start = this.getPosition(y1, x1)
    const end = this.getPosition(y2, x2)
    return new vscode.Range(start, end)
  }
  /**
   * 解析文本内容,并返回格式化后文本
   * @param text 解析文本内容
   * @param enhancerKind 增强的种类 。有些winged支持的语法,需要修饰后再放入prettier解析。
   */
  private parse(text: string, enhancerKind: EnhancerKind): string {
    try {
      let _text = text
      if (enhancerKind.ternary) {
        const { str, flag } = this.enhanceTernary(_text)
        _text = str
        enhancerKind.ternary = flag
      }
      _text = prettier.format(_text, { semi: false, parser: 'babel', singleQuote: true }).trim()
      return this.resloveEnhancer(_text, enhancerKind)
    } catch (error) {
      // console.log(error)
      // throw error.codeFrame
      return text
    }
  }
  /**
   * 增强三目运算符,winged支持省略 : , 这里会在parse之前加入 ':1' 使prettier正常工作
   */
  private enhanceTernary(str: string): { str: string; flag: boolean } {
    let flag = false
    if (str.lastIndexOf('?') !== -1 && str.lastIndexOf(':') === -1) {
      str = str + ':1'
      flag = true
    }
    return { str, flag }
  }
  /**
   * 解决增强剂的副作用
   * 比如三目运算符的增强 需要 在格式化后 去除 之前加入的 ':1'
   */
  private resloveEnhancer(str: string, enhancerKind: EnhancerKind): string {
    if (enhancerKind.ternary) {
      str = str.slice(0, str.length - 3).trim()
    }
    if (enhancerKind.object) {
      const regex = /(\n\s|\n)/g
      const regex2 = /,\}\)/
      str = str.replace(regex, '').replace(regex2, ' })')
    } else {
      // 解决 cond 过长
      const regex = /(\n\s|\n)/g
      str = str.replace(regex, '')
    }
    return str
  }

  private getText(document: vscode.TextDocument, range: vscode.Range) {
    return document.getText(range)
  }
}