// Copyright (C) 2020 Marius Schellenberger

package pve

import (
	"bytes"
	"context"
	"errors"
	"fmt"
	"mime/multipart"
	"net/http"
	"time"
)

var (
	ErrNoSnippetNode    = errors.New("missing snippet target node")
	ErrNoSnippetStorage = errors.New("missing snippet target storage")
	ErrNoSnippetName    = errors.New("missing snippet name")
)

type CopyBuffer struct {
	*bytes.Buffer
}

func (c *CopyBuffer) Copy() *bytes.Buffer {
	buf := make([]byte, c.Len())
	copy(buf, c.Bytes())
	return bytes.NewBuffer(buf)
}

type SnippetClient struct {
	client *Client
}

func (c *SnippetClient) Create(ctx context.Context, node, storage, name string, data []byte) (t *Task, err error) {
	if node == "" {
		err = ErrNoSnippetNode
		return
	}
	if storage == "" {
		err = ErrNoSnippetStorage
		return
	}
	if name == "" {
		err = ErrNoSnippetName
		return
	}
	var b bytes.Buffer
	w := multipart.NewWriter(&b)
	err = w.WriteField("content", "snippets")
	if err != nil {
		return
	}
	fw, err := w.CreateFormFile("filename", name)
	if err != nil {
		return
	}
	if _, err = fw.Write(data); err != nil {
		return
	}
	w.Close()
	cb := CopyBuffer{&b}
	ct := w.FormDataContentType()
	var taskid string
	var req *http.Request
	var resp *http.Response
	for i := 0; i < 3; i++ {
		buf := cb.Copy()
		req, err = c.client.NewRequest(ctx, "POST", fmt.Sprintf("/nodes/%s/storage/%s/upload", node, storage), buf)
		req.Header.Set("Content-Type", ct)
		resp, err = c.client.Do(req, &taskid)
		if err != nil {
			time.Sleep(time.Millisecond * 500)
			// TODO log error
			continue
		}
		if resp.StatusCode != http.StatusOK {
			time.Sleep(time.Millisecond * 500)
			// TODO log error
			continue
		}
		break
	}
	t = c.client.Task.MustGet(ctx, taskid)
	return
}

func SnippetVolume(storage, name string) string {
	return fmt.Sprintf("%s:snippets/%s", storage, name)
}

func (c *SnippetClient) Delete(ctx context.Context, node, storage, name string) (t *Task, err error) {
	//volume := fmt.Sprintf("/%s:snippets/%s", storage, name)
	volume := SnippetVolume(storage, name)
	req, err := c.client.NewRequest(ctx, "DELETE", fmt.Sprintf("/nodes/%s/storage/%s/content/%s", node, storage, volume), nil)
	if err != nil {
		return
	}
	var taskid string
	_, err = c.client.Do(req, &taskid)
	t = c.client.Task.MustGet(ctx, taskid)
	return
}