package client

import (
	"bytes"
	"context"
	"encoding/json"
	"errors"
	"fmt"

	apiclient "git.giftfish.de/ston1th/haproxy-lb/pkg/api/client"
	"git.giftfish.de/ston1th/haproxy-lb/pkg/api/v1/schema"
)

var (
	ErrClientIsNil = errors.New("client is nil")
	base           = "/" + schema.Version
)

type Client struct {
	c *apiclient.Client
}

func NewClient(c *apiclient.Client) (*Client, error) {
	if c == nil {
		return nil, ErrClientIsNil
	}
	return &Client{c}, nil
}

func (c *Client) GetLoadBalancers(ctx context.Context) (lbs map[string]schema.LoadBalancer, err error) {
	return c.GetLoadBalancersWithCluster(ctx, "")
}

func (c *Client) GetLoadBalancersWithCluster(ctx context.Context, cluster string) (lbs map[string]schema.LoadBalancer, err error) {
	path := base + "/lb"
	if cluster != "" {
		path += "/" + cluster
	}
	req, err := c.c.NewRequest(ctx, "GET", path, nil)
	if err != nil {
		return
	}
	lbs = make(map[string]schema.LoadBalancer)
	_, err = c.c.Do(req, &lbs)
	return
}

func (c *Client) GetLoadBalancer(ctx context.Context, cluster, name string) (lb schema.LoadBalancer, err error) {
	path := fmt.Sprintf("%s/lb/%s/%s", base, cluster, name)
	req, err := c.c.NewRequest(ctx, "GET", path, nil)
	if err != nil {
		return
	}
	_, err = c.c.Do(req, &lb)
	return
}

func (c *Client) CreateLoadBalancer(ctx context.Context, cluster, name string, lb schema.LoadBalancer) (err error) {
	buf := new(bytes.Buffer)
	path := fmt.Sprintf("%s/lb/%s/%s", base, cluster, name)
	err = lb.ValidateClient()
	if err != nil {
		return
	}
	err = json.NewEncoder(buf).Encode(lb)
	if err != nil {
		return
	}
	req, err := c.c.NewRequest(ctx, "POST", path, buf)
	if err != nil {
		return
	}
	_, err = c.c.Do(req, nil)
	return
}

func (c *Client) DeleteLoadBalancer(ctx context.Context, cluster, name string) (err error) {
	path := fmt.Sprintf("%s/lb/%s/%s", base, cluster, name)
	req, err := c.c.NewRequest(ctx, "DELETE", path, nil)
	if err != nil {
		return
	}
	_, err = c.c.Do(req, nil)
	return
}

func (c *Client) DeleteLoadBalancersWithCluster(ctx context.Context, cluster string) (err error) {
	if cluster == "" {
		return errors.New("cluster value can not be empty")
	}
	path := base + "/lb/" + cluster
	req, err := c.c.NewRequest(ctx, "DELETE", path, nil)
	if err != nil {
		return
	}
	_, err = c.c.Do(req, nil)
	return
}