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

package provider

import (
	"context"
	"fmt"
	"time"

	"terraform-provider-virtfusion/internal/client"

	"github.com/hashicorp/terraform-plugin-framework/path"
	"github.com/hashicorp/terraform-plugin-framework/resource"
	"github.com/hashicorp/terraform-plugin-framework/resource/schema"
	"github.com/hashicorp/terraform-plugin-framework/resource/schema/mapplanmodifier"
	"github.com/hashicorp/terraform-plugin-framework/resource/schema/planmodifier"
	"github.com/hashicorp/terraform-plugin-framework/resource/schema/stringplanmodifier"
	"github.com/hashicorp/terraform-plugin-framework/types"
)

// Ensure provider-defined types fully satisfy framework interfaces.
var (
	_ resource.Resource              = &ServerPowerActionResource{}
	_ resource.ResourceWithConfigure = &ServerPowerActionResource{}
)

// NewServerPowerActionResource creates a new server power action resource.
func NewServerPowerActionResource() resource.Resource {
	return &ServerPowerActionResource{}
}

// ServerPowerActionResource defines the resource implementation.
type ServerPowerActionResource struct {
	client *client.Client
}

// ServerPowerActionResourceModel describes the resource data model.
type ServerPowerActionResourceModel struct {
	ID       types.String `tfsdk:"id"`
	ServerID types.Int64  `tfsdk:"server_id"`
	Action   types.String `tfsdk:"action"`
	Triggers types.Map    `tfsdk:"triggers"`
}

func (r *ServerPowerActionResource) Metadata(_ context.Context, req resource.MetadataRequest, resp *resource.MetadataResponse) {
	resp.TypeName = req.ProviderTypeName + "_server_power_action"
}

func (r *ServerPowerActionResource) Schema(_ context.Context, _ resource.SchemaRequest, resp *resource.SchemaResponse) {
	resp.Schema = schema.Schema{
		MarkdownDescription: "Performs a power action on a VirtFusion server. This is a trigger-style resource — the action is executed on create and can be re-triggered by changing the `triggers` attribute.",
		Attributes: map[string]schema.Attribute{
			"id": schema.StringAttribute{
				MarkdownDescription: "The identifier for this power action.",
				Computed:            true,
				PlanModifiers: []planmodifier.String{
					stringplanmodifier.UseStateForUnknown(),
				},
			},
			"server_id": schema.Int64Attribute{
				MarkdownDescription: "The ID of the server to perform the power action on.",
				Required:            true,
			},
			"action": schema.StringAttribute{
				MarkdownDescription: "The power action to perform. Must be one of: `boot`, `shutdown`, `restart`, `poweroff`.",
				Required:            true,
			},
			"triggers": schema.MapAttribute{
				MarkdownDescription: "A map of arbitrary strings that, when changed, will cause the power action to be re-executed. Works like `triggers` in `terraform_data`.",
				ElementType:         types.StringType,
				Optional:            true,
				PlanModifiers: []planmodifier.Map{
					mapplanmodifier.RequiresReplace(),
				},
			},
		},
	}
}

func (r *ServerPowerActionResource) Configure(_ context.Context, req resource.ConfigureRequest, resp *resource.ConfigureResponse) {
	if req.ProviderData == nil {
		return
	}

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

	r.client = c
}

func (r *ServerPowerActionResource) Create(ctx context.Context, req resource.CreateRequest, resp *resource.CreateResponse) {
	var data ServerPowerActionResourceModel
	resp.Diagnostics.Append(req.Plan.Get(ctx, &data)...)
	if resp.Diagnostics.HasError() {
		return
	}

	apiPath := fmt.Sprintf("/servers/%d/power/%s", data.ServerID.ValueInt64(), data.Action.ValueString())
	_, err := r.client.Post(ctx, apiPath, nil)
	if err != nil {
		resp.Diagnostics.AddError(
			"Error Performing Server Power Action",
			fmt.Sprintf("Could not perform power action %q on server %d: %s", data.Action.ValueString(), data.ServerID.ValueInt64(), err),
		)
		return
	}

	data.ID = types.StringValue(fmt.Sprintf("%d-%s-%d", data.ServerID.ValueInt64(), data.Action.ValueString(), time.Now().UnixNano()))

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

func (r *ServerPowerActionResource) Read(ctx context.Context, req resource.ReadRequest, resp *resource.ReadResponse) {
	var data ServerPowerActionResourceModel
	resp.Diagnostics.Append(req.State.Get(ctx, &data)...)
	if resp.Diagnostics.HasError() {
		return
	}

	// Return stored state as-is for trigger-style resources.
	resp.Diagnostics.Append(resp.State.Set(ctx, &data)...)
}

func (r *ServerPowerActionResource) Update(ctx context.Context, req resource.UpdateRequest, resp *resource.UpdateResponse) {
	var data ServerPowerActionResourceModel
	resp.Diagnostics.Append(req.Plan.Get(ctx, &data)...)
	if resp.Diagnostics.HasError() {
		return
	}

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

func (r *ServerPowerActionResource) Delete(_ context.Context, _ resource.DeleteRequest, _ *resource.DeleteResponse) {
	// No-op: power actions are not reversible. Removing from state only.
}

// ValidateConfig validates the resource configuration.
func (r *ServerPowerActionResource) ValidateConfig(ctx context.Context, req resource.ValidateConfigRequest, resp *resource.ValidateConfigResponse) {
	var data ServerPowerActionResourceModel
	resp.Diagnostics.Append(req.Config.Get(ctx, &data)...)
	if resp.Diagnostics.HasError() {
		return
	}

	// Validate server_id is positive.
	if !data.ServerID.IsNull() && !data.ServerID.IsUnknown() && data.ServerID.ValueInt64() <= 0 {
		resp.Diagnostics.AddAttributeError(
			path.Root("server_id"),
			"Invalid Server ID",
			"server_id must be a positive integer.",
		)
	}

	// Validate action is one of the allowed values.
	if !data.Action.IsNull() && !data.Action.IsUnknown() {
		action := data.Action.ValueString()
		validActions := map[string]bool{
			"boot":     true,
			"shutdown": true,
			"restart":  true,
			"poweroff": true,
		}
		if !validActions[action] {
			resp.Diagnostics.AddAttributeError(
				path.Root("action"),
				"Invalid Power Action",
				fmt.Sprintf("action must be one of: boot, shutdown, restart, poweroff. Got: %q", action),
			)
		}
	}
}