const util = require('curlconverter/util')
const jsesc = require('jsesc')
const querystring = require('query-string')
const fs = require('fs')

require('string.prototype.startswith')

function reprWithVariable(value, hasEnvironmentVariable) {
    if (!value) {
        return "''"
    }

    if (!hasEnvironmentVariable) {
        return "'" + jsesc(value, {quotes: 'single'}) + "'"
    }

    return 'f"' + jsesc(value, {quotes: 'double'}) + '"'
}

function repr(value) {
    // In context of url parameters, don't accept nulls and such.
    return reprWithVariable(value, false)
}

function getQueryDict(request) {
    let queryDict = 'params = (\n'
    for (const paramName in request.query) {
        const rawValue = request.query[paramName]
        let paramValue
        if (Array.isArray(rawValue)) {
            paramValue = '[' + rawValue.map(repr).join(', ') + ']'
        } else {
            paramValue = repr(rawValue)
        }
        queryDict += '    (' + repr(paramName) + ', ' + paramValue + '    ),\n'
    }
    queryDict += '    )\n'
    return queryDict
}

function getDataString(request) {
    if (typeof request.data === 'number') {
        request.data = request.data.toString()
    }
    if (!request.isDataRaw && request.data.startsWith('@')) {
        const filePath = request.data.slice(1)
        if (request.isDataBinary) {
            return 'data = open(\'' + filePath + '\', \'rb\').read()'
        } else {
            return 'data = open(\'' + filePath + '\')'
        }
    }

    const parsedQueryString = querystring.parse(request.data, {sort: false})
    const keyCount = Object.keys(parsedQueryString).length
    const singleKeyOnly = keyCount === 1 && !parsedQueryString[Object.keys(parsedQueryString)[0]]
    const singularData = request.isDataBinary || singleKeyOnly
    if (singularData) {
        return 'data = ' + repr(request.data) + '\n'
    } else {
        return getMultipleDataString(request, parsedQueryString)
    }
}

function getMultipleDataString(request, parsedQueryString) {
    let repeatedKey = false
    for (const key in parsedQueryString) {
        const value = parsedQueryString[key]
        if (Array.isArray(value)) {
            repeatedKey = true
        }
    }

    let dataString
    if (repeatedKey) {
        dataString = 'data = [\n'
        for (const key in parsedQueryString) {
            const value = parsedQueryString[key]
            if (Array.isArray(value)) {
                for (let i = 0; i < value.length; i++) {
                    dataString += '  (' + repr(key) + ', ' + repr(value[i]) + '),\n'
                }
            } else {
                dataString += '  (' + repr(key) + ', ' + repr(value) + '),\n'
            }
        }
        dataString += ']\n'
    } else {
        dataString = 'data = {\n'
        const elementCount = Object.keys(parsedQueryString).length
        let i = 0
        for (const key in parsedQueryString) {
            const value = parsedQueryString[key]
            dataString += '  ' + repr(key) + ': ' + repr(value)
            if (i === elementCount - 1) {
                dataString += '\n'
            } else {
                dataString += ',\n'
            }
            ++i
        }
        dataString += '}\n'
    }

    return dataString
}

function getFilesString(request) {
    // http://docs.python-requests.org/en/master/user/quickstart/#post-a-multipart-encoded-file
    let filesString = 'files = {\n'
    for (const multipartKey in request.multipartUploads) {
        const multipartValue = request.multipartUploads[multipartKey]
        if (multipartValue.startsWith('@')) {
            const fileName = multipartValue.slice(1)
            filesString += '    ' + repr(multipartKey) + ': (' + repr(fileName) + ', open(' + repr(fileName) + ", 'rb')),\n"
        } else {
            filesString += '    ' + repr(multipartKey) + ': (None, ' + repr(multipartValue) + '),\n'
        }
    }
    filesString += '}\n'

    return filesString
}

// convertVarToStringFormat will convert if inputString to f"..." format
// if inputString has possible variable as its substring
function detectEnvVar(inputString) {
    // Using state machine to detect environment variable
    // Each character is an edge, state machine:
    // IN_ENV_VAR: means that currently we are iterating inside a possible environment variable
    // IN_STRING: means that currently we are iterating inside a normal string
    // For example:
    // "Hi my name is $USER_NAME !"
    // '$' --> will move state from IN_STRING to IN_ENV_VAR
    // ' ' --> will move state to IN_STRING, regardless the previous state

    const IN_ENV_VAR = 0
    const IN_STRING = 1

    // We only care for the unique element
    const detectedVariables = new Set()
    let currState = IN_STRING
    let envVarStartIndex = -1

    const whiteSpaceSet = new Set()
    whiteSpaceSet.add(' ')
    whiteSpaceSet.add('\n')
    whiteSpaceSet.add('    ')

    const modifiedString = []
    for (const idx in inputString) {
        const currIdx = +idx
        const currChar = inputString[currIdx]
        if (currState === IN_ENV_VAR && whiteSpaceSet.has(currChar)) {
            const newVariable = inputString.substring(envVarStartIndex, currIdx)

            if (newVariable !== '') {
                detectedVariables.add(newVariable)

                // Change $ -> {
                // Add } after the last variable name
                modifiedString.push('{' + newVariable + '}' + currChar)
            } else {
                modifiedString.push('$' + currChar)
            }
            currState = IN_STRING
            envVarStartIndex = -1
            continue
        }

        if (currState === IN_ENV_VAR) {
            // Skip until we actually have the new variable
            continue
        }

        // currState === IN_STRING
        if (currChar === '$') {
            currState = IN_ENV_VAR
            envVarStartIndex = currIdx + 1
        } else {
            modifiedString.push(currChar)
        }
    }

    if (currState === IN_ENV_VAR) {
        const newVariable = inputString.substring(envVarStartIndex, inputString.length)

        if (newVariable !== '') {
            detectedVariables.add(newVariable)
            modifiedString.push('{' + newVariable + '}')
        } else {
            modifiedString.push('$')
        }
    }

    return [detectedVariables, modifiedString.join('')]
}

const toPython = curlCommand => {
    const request = util.parseCurlCommand(curlCommand)

    // Currently, only assuming that the env-var only used in
    // the value part of cookies, params, or body
    const osVariables = new Set()

    let cookieDict
    if (request.cookies) {
        cookieDict = 'cookies = {\n'
        for (const cookieName in request.cookies) {
            const [detectedVars, modifiedString] = detectEnvVar(request.cookies[cookieName])

            const hasEnvironmentVariable = detectedVars.size > 0

            for (const newVar of detectedVars) {
                osVariables.add(newVar)
            }

            cookieDict += '        ' + repr(cookieName) + ': ' + reprWithVariable(modifiedString, hasEnvironmentVariable) + ',\n'
        }
        cookieDict += '    }\n'
    }
    let headerDict
    if (request.headers) {
        headerDict = 'headers = {\n'
        for (const headerName in request.headers) {
            const [detectedVars, modifiedString] = detectEnvVar(request.headers[headerName])

            const hasVariable = detectedVars.size > 0

            for (const newVar of detectedVars) {
                osVariables.add(newVar)
            }

            headerDict += '        ' + repr(headerName) + ': ' + reprWithVariable(modifiedString, hasVariable) + ',\n'
        }
        headerDict += '    }\n'
    }

    let queryDict
    if (request.query) {
        queryDict = getQueryDict(request)
    }

    let dataString
    let filesString
    if (typeof request.data === 'string' || typeof request.data === 'number') {
        dataString = getDataString(request)
    } else if (request.multipartUploads) {
        filesString = getFilesString(request)
    }
    // curl automatically prepends 'http' if the scheme is missing, but python fails and returns an error
    // we tack it on here to mimic curl
    if (!request.url.match(/https?:/)) {
        request.url = 'http://' + request.url
    }
    if (!request.urlWithoutQuery.match(/https?:/)) {
        request.urlWithoutQuery = 'http://' + request.urlWithoutQuery
    }
    let requestLineWithUrlParams = '    response = requests.' + request.method + '(\'' + request.urlWithoutQuery + '\''
    let requestLineWithOriginalUrl = 'response = requests.' + request.method + '(\'' + request.url + '\''

    let requestLineBody = ''
    if (request.headers) {
        requestLineBody += ', headers=headers'
    }
    if (request.query) {
        requestLineBody += ', params=params'
    }
    if (request.cookies) {
        requestLineBody += ', cookies=cookies'
    }
    if (typeof request.data === 'string') {
        requestLineBody += ', data=data'
    } else if (request.multipartUploads) {
        requestLineBody += ', files=files'
    }
    if (request.insecure) {
        requestLineBody += ', verify=False'
    }
    if (request.auth) {
        const splitAuth = request.auth.split(':')
        const user = splitAuth[0] || ''
        const password = splitAuth[1] || ''
        requestLineBody += ', auth=(' + repr(user) + ', ' + repr(password) + '    )'
    }
    requestLineBody += ')\n'

    requestLineWithOriginalUrl += requestLineBody.replace(', params=params', '')
    requestLineWithUrlParams += requestLineBody

    let pythonCode = ''

    // Sort import by name
    if (osVariables.size > 0) {
        pythonCode += 'import os\n'
    }
    pythonCode += "# -*- coding: utf-8 -*-\n\n"

    pythonCode += 'import requests\n\n\ndef fetch():\n'

    if (osVariables.size > 0) {
        for (const osVar of osVariables) {
            const line = `${osVar} = os.getenv('${osVar}')\n`
            pythonCode += line
        }

        pythonCode += '\n'
    }

    if (cookieDict) {
        pythonCode += "    " + cookieDict + '\n'
    }
    if (headerDict) {
        pythonCode += "    " + headerDict + '\n'
    }
    if (queryDict) {
        pythonCode += "    " + queryDict + '\n'
    }
    if (dataString) {
        pythonCode += "    " + dataString + '\n'
    } else if (filesString) {
        pythonCode += "    " + filesString + '\n'
    }
    pythonCode += requestLineWithUrlParams
    pythonCode += "    response.encoding = response.apparent_encoding\n"
    pythonCode += "    print(response.text)\n"


    if (request.query) {
        pythonCode += '\n\n    #一行代码表示\n    #' + requestLineWithOriginalUrl
    }
    filename=request.url.split(".")[1]
    pythonCode += `
  
if __name__ == '__main__':
    fetch()`

    return pythonCode+"\n"
}
const writFile=(mypythoncode)=>{
  fs.writeFile(`/Users/chennan/_demo/${filename}.py`, mypythoncode, function (error) {
      if (error) {
          console.log(`生成代码失败:${error}`);
      } else {
          console.log('生成Python代码成功,文件名temp.py')
      }
  })

}

const curlcode = `
curl 'http://www.gjgwy.org/wenda-0-99-0-6.html' \\
  -H 'Connection: keep-alive' \\
  -H 'Upgrade-Insecure-Requests: 1' \\
  -H 'User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.54 Safari/537.36' \\
  -H 'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9' \\
  -H 'Referer: http://www.gjgwy.org/wenda-0-99-0-5.html' \\
  -H 'Accept-Language: zh-CN,zh;q=0.9' \\
  -H 'Cookie: PHPSESSID=k2ornhgl2s3gmtr5avl85dr6d5; Hm_lvt_ccef5e9cf2ef393614182f20b2c637cc=1635153249; _ga=GA1.2.1219935519.1635153249; _gid=GA1.2.1270463396.1635153249; show-alert-small=1; Hm_lpvt_ccef5e9cf2ef393614182f20b2c637cc=1635153309' \\
  --compressed \\
  --insecure
`
const mypythoncode = toPython(curlcode)
writFile(mypythoncode)