package api

import (
	"errors"
	"fmt"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/gotify/server/v2/auth"
	"github.com/gotify/server/v2/model"
)

// The ClientDatabase interface for encapsulating database access.
type ClientDatabase interface {
	CreateClient(client *model.Client) error
	GetClientByToken(token string) (*model.Client, error)
	GetClientByID(id uint) (*model.Client, error)
	GetClientsByUser(userID uint) ([]*model.Client, error)
	DeleteClientByID(id uint) error
	UpdateClient(client *model.Client) error
	UpdateClientElevatedUntil(id uint, t *time.Time) error
}

// The ClientAPI provides handlers for managing clients and applications.
type ClientAPI struct {
	DB            ClientDatabase
	ImageDir      string
	NotifyDeleted func(uint, string)
}

// Client Params Model
//
// Params allowed to create or update Clients.
//
// swagger:model ClientParams
type ClientParams struct {
	// The client name
	//
	// required: true
	// example: My Client
	Name string `form:"name" query:"name" json:"name" binding:"required"`
}

// UpdateClient updates a client by its id.
// swagger:operation PUT /client/{id} client updateClient
//
// Update a client.
//
//	---
//	consumes: [application/json]
//	produces: [application/json]
//	security: [clientTokenAuthorizationHeader: [], clientTokenHeader: [], clientTokenQuery: [], basicAuth: []]
//	parameters:
//	- name: body
//	  in: body
//	  description: the client to update
//	  required: true
//	  schema:
//	    $ref: "#/definitions/ClientParams"
//	- name: id
//	  in: path
//	  description: the client id
//	  required: true
//	  type: integer
//	  format: int64
//	responses:
//	  200:
//	    description: Ok
//	    schema:
//	        $ref: "#/definitions/Client"
//	  400:
//	    description: Bad Request
//	    schema:
//	        $ref: "#/definitions/Error"
//	  401:
//	    description: Unauthorized
//	    schema:
//	        $ref: "#/definitions/Error"
//	  403:
//	    description: Forbidden
//	    schema:
//	        $ref: "#/definitions/Error"
//	  404:
//	    description: Not Found
//	    schema:
//	        $ref: "#/definitions/Error"
func (a *ClientAPI) UpdateClient(ctx *gin.Context) {
	withID(ctx, "id", func(id uint) {
		client, err := a.DB.GetClientByID(id)
		if success := successOrAbort(ctx, 500, err); !success {
			return
		}
		if client != nil && client.UserID == auth.GetUserID(ctx) {
			newValues := ClientParams{}
			if err := ctx.Bind(&newValues); err == nil {
				client.Name = newValues.Name

				if success := successOrAbort(ctx, 500, a.DB.UpdateClient(client)); !success {
					return
				}
				ctx.JSON(200, client)
			}
		} else {
			ctx.AbortWithError(404, fmt.Errorf("client with id %d doesn't exists", id))
		}
	})
}

// CreateClient creates a client and returns the access token.
// swagger:operation POST /client client createClient
//
// Create a client.
//
//	---
//	consumes: [application/json]
//	produces: [application/json]
//	security: [clientTokenAuthorizationHeader: [], clientTokenHeader: [], clientTokenQuery: [], basicAuth: []]
//	parameters:
//	- name: body
//	  in: body
//	  description: the client to add
//	  required: true
//	  schema:
//	    $ref: "#/definitions/ClientParams"
//	responses:
//	  200:
//	    description: Ok
//	    schema:
//	        $ref: "#/definitions/Client"
//	  400:
//	    description: Bad Request
//	    schema:
//	        $ref: "#/definitions/Error"
//	  401:
//	    description: Unauthorized
//	    schema:
//	        $ref: "#/definitions/Error"
//	  403:
//	    description: Forbidden
//	    schema:
//	        $ref: "#/definitions/Error"
func (a *ClientAPI) CreateClient(ctx *gin.Context) {
	clientParams := ClientParams{}
	if err := ctx.Bind(&clientParams); err == nil {
		client := model.Client{
			Name:   clientParams.Name,
			Token:  auth.GenerateNotExistingToken(generateClientToken, a.clientExists),
			UserID: auth.GetUserID(ctx),
		}

		if success := successOrAbort(ctx, 500, a.DB.CreateClient(&client)); !success {
			return
		}
		ctx.JSON(200, client)
	}
}

// GetClients returns all clients a user has.
// swagger:operation GET /client client getClients
//
// Return all clients.
//
//	---
//	consumes: [application/json]
//	produces: [application/json]
//	security: [clientTokenAuthorizationHeader: [], clientTokenHeader: [], clientTokenQuery: [], basicAuth: []]
//	responses:
//	  200:
//	    description: Ok
//	    schema:
//	      type: array
//	      items:
//	        $ref: "#/definitions/Client"
//	  401:
//	    description: Unauthorized
//	    schema:
//	        $ref: "#/definitions/Error"
//	  403:
//	    description: Forbidden
//	    schema:
//	        $ref: "#/definitions/Error"
func (a *ClientAPI) GetClients(ctx *gin.Context) {
	userID := auth.GetUserID(ctx)
	clients, err := a.DB.GetClientsByUser(userID)
	if success := successOrAbort(ctx, 500, err); !success {
		return
	}
	now := time.Now()
	for _, client := range clients {
		if client.ElevatedUntil != nil && !now.Before(*client.ElevatedUntil) {
			client.ElevatedUntil = nil
		}
	}
	ctx.JSON(200, clients)
}

// DeleteClient deletes a client by its id.
// swagger:operation DELETE /client/{id} client deleteClient
//
// Delete a client.
//
// Requires elevated authentication.
//
//	---
//	consumes: [application/json]
//	produces: [application/json]
//	parameters:
//	- name: id
//	  in: path
//	  description: the client id
//	  required: true
//	  type: integer
//	  format: int64
//	security: [clientTokenAuthorizationHeader: [], clientTokenHeader: [], clientTokenQuery: [], basicAuth: []]
//	responses:
//	  200:
//	    description: Ok
//	  400:
//	    description: Bad Request
//	    schema:
//	        $ref: "#/definitions/Error"
//	  401:
//	    description: Unauthorized
//	    schema:
//	        $ref: "#/definitions/Error"
//	  403:
//	    description: Forbidden
//	    schema:
//	        $ref: "#/definitions/Error"
//	  404:
//	    description: Not Found
//	    schema:
//	        $ref: "#/definitions/Error"
func (a *ClientAPI) DeleteClient(ctx *gin.Context) {
	withID(ctx, "id", func(id uint) {
		client, err := a.DB.GetClientByID(id)
		if success := successOrAbort(ctx, 500, err); !success {
			return
		}
		if client != nil && client.UserID == auth.GetUserID(ctx) {
			a.NotifyDeleted(client.UserID, client.Token)
			successOrAbort(ctx, 500, a.DB.DeleteClientByID(id))
		} else {
			ctx.AbortWithError(404, fmt.Errorf("client with id %d doesn't exists", id))
		}
	})
}

// swagger:operation POST /client/{id}/elevate client elevateClient
//
// Elevate a client session.
//
// Requires elevated authentication.
//
//	---
//	consumes: [application/json]
//	produces: [application/json]
//	parameters:
//	- name: id
//	  in: path
//	  description: the client id
//	  required: true
//	  type: integer
//	  format: int64
//	- name: body
//	  in: body
//	  description: the elevation request
//	  required: true
//	  schema:
//	    $ref: "#/definitions/ElevateRequest"
//	security: [clientTokenAuthorizationHeader: [], clientTokenHeader: [], clientTokenQuery: [], basicAuth: []]
//	responses:
//	  204:
//	    description: Ok
//	  400:
//	    description: Bad Request
//	    schema:
//	        $ref: "#/definitions/Error"
//	  401:
//	    description: Unauthorized
//	    schema:
//	        $ref: "#/definitions/Error"
//	  404:
//	    description: Not Found
//	    schema:
//	        $ref: "#/definitions/Error"
func (a *ClientAPI) ElevateClient(ctx *gin.Context) {
	withID(ctx, "id", func(id uint) {
		var params model.ElevateRequest
		if err := ctx.Bind(&params); err != nil {
			return
		}

		client, err := a.DB.GetClientByID(id)
		if err != nil {
			ctx.AbortWithError(500, err)
			return
		}
		if client == nil || client.UserID != auth.GetUserID(ctx) {
			ctx.AbortWithError(404, errors.New("client not found"))
			return
		}

		elevatedUntil := time.Now().Add(time.Duration(params.DurationSeconds) * time.Second)
		if err := a.DB.UpdateClientElevatedUntil(client.ID, &elevatedUntil); err != nil {
			ctx.AbortWithError(500, err)
			return
		}

		ctx.Status(204)
	})
}

func (a *ClientAPI) clientExists(token string) bool {
	client, _ := a.DB.GetClientByToken(token)
	return client != nil
}