// Copyright (c) EZSCALE.
// SPDX-License-Identifier: MPL-2.0

package provider

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

	"terraform-provider-virtfusion/internal/client"

	"github.com/hashicorp/terraform-plugin-framework/datasource"
	"github.com/hashicorp/terraform-plugin-framework/datasource/schema"
	"github.com/hashicorp/terraform-plugin-framework/types"
)

var _ datasource.DataSource = &ServerTrafficDataSource{}
var _ datasource.DataSourceWithConfigure = &ServerTrafficDataSource{}

// NewServerTrafficDataSource returns a new data source for reading server traffic.
func NewServerTrafficDataSource() datasource.DataSource {
	return &ServerTrafficDataSource{}
}

// ServerTrafficDataSource defines the data source implementation.
type ServerTrafficDataSource struct {
	client *client.Client
}

// ServerTrafficDataSourceModel describes the data source data model.
type ServerTrafficDataSourceModel struct {
	ServerID types.Int64 `tfsdk:"server_id"`
	Used     types.Int64 `tfsdk:"used"`
	Limit    types.Int64 `tfsdk:"limit"`
}

func (d *ServerTrafficDataSource) Metadata(_ context.Context, req datasource.MetadataRequest, resp *datasource.MetadataResponse) {
	resp.TypeName = req.ProviderTypeName + "_server_traffic"
}

func (d *ServerTrafficDataSource) Schema(_ context.Context, _ datasource.SchemaRequest, resp *datasource.SchemaResponse) {
	resp.Schema = schema.Schema{
		MarkdownDescription: "Use this data source to read traffic usage for a VirtFusion server.",
		Attributes: map[string]schema.Attribute{
			"server_id": schema.Int64Attribute{
				MarkdownDescription: "The server ID to read traffic for.",
				Required:            true,
			},
			"used": schema.Int64Attribute{
				MarkdownDescription: "The amount of traffic used.",
				Computed:            true,
			},
			"limit": schema.Int64Attribute{
				MarkdownDescription: "The traffic limit.",
				Computed:            true,
			},
		},
	}
}

func (d *ServerTrafficDataSource) Configure(_ context.Context, req datasource.ConfigureRequest, resp *datasource.ConfigureResponse) {
	if req.ProviderData == nil {
		return
	}

	c, ok := req.ProviderData.(*client.Client)
	if !ok {
		resp.Diagnostics.AddError(
			"Unexpected Data Source Configure Type",
			fmt.Sprintf("Expected *client.Client, got: %T. Please report this issue to the provider developers.", req.ProviderData),
		)
		return
	}

	d.client = c
}

func (d *ServerTrafficDataSource) Read(ctx context.Context, req datasource.ReadRequest, resp *datasource.ReadResponse) {
	var data ServerTrafficDataSourceModel
	resp.Diagnostics.Append(req.Config.Get(ctx, &data)...)
	if resp.Diagnostics.HasError() {
		return
	}

	result, err := d.client.Get(ctx, fmt.Sprintf("/servers/%d/traffic", data.ServerID.ValueInt64()))
	if err != nil {
		resp.Diagnostics.AddError("Error Reading Server Traffic", err.Error())
		return
	}

	var trafficResp client.TrafficResponse
	if err := json.Unmarshal(result, &trafficResp); err != nil {
		resp.Diagnostics.AddError("Error Parsing Server Traffic Response", err.Error())
		return
	}

	data.Used = types.Int64Value(trafficResp.Data.Used)
	data.Limit = types.Int64Value(trafficResp.Data.Limit)

	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)
}