//解释请求内容，放到相应的成员变量中

package ecgo

import (
	"encoding/json"
	"errors"
	"net/http"
	"net/url"
	"strings"
)

// Request 请求对象
type Request struct {
	RawData string
	*http.Request
	data   map[string]string
	parsed bool
}

// NewRequest 创建Request对象
func NewRequest(req *http.Request) *Request {
	data := make(map[string]string)
	body := make([]byte, req.ContentLength)
	req.Body.Read(body)
	return &Request{
		string(body),
		req,
		data,
		false,
	}
}

func (req *Request) parse() {
	if !req.parsed {
		req.ParseForm()
		contentType := strings.ToLower(req.Header.Get("Content-Type"))
		if strings.HasPrefix(contentType, "multipart/form-data") {
			req.ParseMultipartForm(10 << 20)
		}
		var vals url.Values
		if req.MultipartForm != nil {
			vals = req.MultipartForm.Value
		} else {
			vals = req.PostForm
		}
		for k, v := range vals {
			if _, ok := req.data[k]; !ok {
				req.data[k] = v[0]
			}
		}
		for k, v := range req.Form {
			if _, ok := req.data[k]; !ok {
				req.data[k] = v[0]
			}
		}

		req.parsed = true
	}
}

// GetHeader 获取指定名称的请求头
func (req *Request) GetHeader(key string) string {
	return req.Header.Get(key)
}

// Input 获取指定的请求参数内容，以字符串类型返回
// 		Input(key) 获取请求参数，未设置时返回空字符串
//      Input(key, defaultVal) 获取请求参数，不存在时返回defaultVal
func (req *Request) Input(key string, defaultVal ...string) string {
	req.parse()
	val, exists := req.data[key]
	if !exists {
		if len(defaultVal) > 0 {
			val = defaultVal[0]
		} else {
			val = ""
		}
	}
	return val
}

// Inputs 返回指定的请求参数，返回map
// 		Inputs() 获取全部请求参数
//		Inputs(key1, key2, ...) 返回指定的参数,不存在的参数值为空字符串
func (req *Request) Inputs(keys ...string) map[string]string {
	req.parse()
	result := make(map[string]string)
	switch len(keys) {
	case 0:
		result = req.data
	default:
		for _, k := range keys {
			if val, exists := req.data[k]; exists {
				result[k] = val
			} else {
				result[k] = ""
			}
		}
	}
	return result
}

// ParseJson 将json字符串格式的原始数据decode到result
func (req *Request) ParseJson(result interface{}) error {
	if !strings.HasPrefix(strings.ToLower(req.Header.Get("Content-Type")), "application/json") {
		return errors.New("not application/json request")
	}
	return json.Unmarshal([]byte(req.RawData), result)
}