// 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/attr"
	"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 = &ServerTemplatesDataSource{}
var _ datasource.DataSourceWithConfigure = &ServerTemplatesDataSource{}

// NewServerTemplatesDataSource returns a new data source for listing server templates.
func NewServerTemplatesDataSource() datasource.DataSource {
	return &ServerTemplatesDataSource{}
}

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

// ServerTemplatesDataSourceModel describes the data source data model.
type ServerTemplatesDataSourceModel struct {
	ServerID  types.Int64 `tfsdk:"server_id"`
	Results   types.Int64 `tfsdk:"results"`
	Templates types.List  `tfsdk:"templates"`
}

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

func (d *ServerTemplatesDataSource) Schema(_ context.Context, _ datasource.SchemaRequest, resp *datasource.SchemaResponse) {
	resp.Schema = schema.Schema{
		MarkdownDescription: "Use this data source to list available templates for a VirtFusion server.",
		Attributes: map[string]schema.Attribute{
			"server_id": schema.Int64Attribute{
				MarkdownDescription: "The server ID to list templates for.",
				Required:            true,
			},
			"results": resultsSchemaAttribute(),
			"templates": schema.ListNestedAttribute{
				MarkdownDescription: "The list of available templates.",
				Computed:            true,
				NestedObject: schema.NestedAttributeObject{
					Attributes: map[string]schema.Attribute{
						"id": schema.Int64Attribute{
							MarkdownDescription: "The template ID.",
							Computed:            true,
						},
						"name": schema.StringAttribute{
							MarkdownDescription: "The template name.",
							Computed:            true,
						},
					},
				},
			},
		},
	}
}

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

	result, err := d.client.GetAllPages(ctx, fmt.Sprintf("/servers/%d/templates?%s", data.ServerID.ValueInt64(), resultsQueryParam(data.Results)))
	if err != nil {
		resp.Diagnostics.AddError("Error Reading Server Templates", err.Error())
		return
	}

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

	templateAttrTypes := map[string]attr.Type{
		"id":   types.Int64Type,
		"name": types.StringType,
	}

	templateObjects := make([]attr.Value, len(templateResp.Data))
	for i, t := range templateResp.Data {
		obj, diags := types.ObjectValue(
			templateAttrTypes,
			map[string]attr.Value{
				"id":   types.Int64Value(t.ID),
				"name": types.StringValue(t.Name),
			},
		)
		resp.Diagnostics.Append(diags...)
		if resp.Diagnostics.HasError() {
			return
		}
		templateObjects[i] = obj
	}

	templatesList, diags := types.ListValue(types.ObjectType{AttrTypes: templateAttrTypes}, templateObjects)
	resp.Diagnostics.Append(diags...)
	if resp.Diagnostics.HasError() {
		return
	}

	data.Templates = templatesList

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