// 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              = &PackageTemplatesDataSource{}
	_ datasource.DataSourceWithConfigure = &PackageTemplatesDataSource{}
)

// NewPackageTemplatesDataSource returns a new package templates data source.
func NewPackageTemplatesDataSource() datasource.DataSource {
	return &PackageTemplatesDataSource{}
}

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

// PackageTemplatesDataSourceModel describes the data source data model.
type PackageTemplatesDataSourceModel struct {
	PackageID types.Int64                `tfsdk:"package_id"`
	Results   types.Int64                `tfsdk:"results"`
	Templates []PackageTemplateItemModel `tfsdk:"templates"`
}

// PackageTemplateItemModel describes a single template in the list.
type PackageTemplateItemModel struct {
	ID   types.Int64  `tfsdk:"id"`
	Name types.String `tfsdk:"name"`
}

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

func (d *PackageTemplatesDataSource) Schema(_ context.Context, _ datasource.SchemaRequest, resp *datasource.SchemaResponse) {
	resp.Schema = schema.Schema{
		MarkdownDescription: "Fetches templates available for a VirtFusion server package.",
		Attributes: map[string]schema.Attribute{
			"package_id": schema.Int64Attribute{
				MarkdownDescription: "The package ID to fetch templates for.",
				Required:            true,
			},
			"results": resultsSchemaAttribute(),
			"templates": schema.ListNestedAttribute{
				MarkdownDescription: "List of templates available for the package.",
				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 *PackageTemplatesDataSource) 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.", req.ProviderData),
		)
		return
	}

	d.client = c
}

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

	rawResp, err := d.client.GetAllPages(ctx, fmt.Sprintf("/media/templates/fromServerPackageSpec/%d?%s", data.PackageID.ValueInt64(), resultsQueryParam(data.Results)))
	if err != nil {
		resp.Diagnostics.AddError("Error Reading Package Templates", err.Error())
		return
	}

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

	data.Templates = make([]PackageTemplateItemModel, len(templateResp.Data))
	for i, t := range templateResp.Data {
		data.Templates[i] = PackageTemplateItemModel{
			ID:   types.Int64Value(t.ID),
			Name: types.StringValue(t.Name),
		}
	}

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