package v1

import (
	"net/http"

	"github.com/gin-gonic/gin"

	"github.com/gochat/gochat/internal/model"
	"github.com/gochat/gochat/internal/repository"
	"github.com/gochat/gochat/pkg/response"
)

// PlatformAgentBotHandler handles Platform API agent bot endpoints (AccessToken auth).
// Reference: Chatwoot Platform::Api::V1::AgentBotsController — AccessToken authenticated
//
// Distinct from account-level AgentBotHandler: this uses AccessToken authentication
// + Permissible system for resource-level access control.
// Platform-level bots (account_id == nil) and account-scoped bots are both accessible.
type PlatformAgentBotHandler struct {
	agentBotRepo    *repository.AgentBotRepo
	permissibleRepo *repository.PermissibleRepo
}

// NewPlatformAgentBotHandler creates a new PlatformAgentBot handler.
func NewPlatformAgentBotHandler(
	agentBotRepo *repository.AgentBotRepo,
	permissibleRepo *repository.PermissibleRepo,
) *PlatformAgentBotHandler {
	return &PlatformAgentBotHandler{
		agentBotRepo:    agentBotRepo,
		permissibleRepo: permissibleRepo,
	}
}

// List returns all agent bots the PlatformApp has permissible access to.
// GET /platform/api/v1/agent_bots
// Reference: Chatwoot Platform::Api::V1::AgentBotsController#index
func (h *PlatformAgentBotHandler) List(c *gin.Context) {
	platformAppID := getPlatformAppID(c)

	permissibles, err := h.permissibleRepo.FindByPlatformAppID(c.Request.Context(), platformAppID)
	if err != nil {
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, err.Error())
		return
	}

	var bots []model.AgentBot
	for _, perm := range permissibles {
		if perm.PermissibleType == model.PermissibleTypeAgentBot {
			bot, err := h.agentBotRepo.FindByID(c.Request.Context(), perm.PermissibleID)
			if err != nil {
				continue
			}
			bots = append(bots, *bot)
		}
	}

	response.OK(c, bots)
}

// Show retrieves an agent bot by ID.
// GET /platform/api/v1/agent_bots/:id
// Reference: Chatwoot Platform::Api::V1::AgentBotsController#show
// Requires: Permissible verification
func (h *PlatformAgentBotHandler) Show(c *gin.Context) {
	botID, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid bot ID")
		return
	}

	platformAppID := getPlatformAppID(c)

	// Verify Permissible access
	perm, err := h.permissibleRepo.FindByPlatformAppAndResource(c.Request.Context(), platformAppID, model.PermissibleTypeAgentBot, botID)
	if err != nil || perm == nil {
		response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden, "non permissible resource")
		return
	}

	bot, err := h.agentBotRepo.FindByID(c.Request.Context(), botID)
	if err != nil {
		response.AbortWithStatusError(c, http.StatusNotFound, response.ErrNotFound, "agent bot not found")
		return
	}

	response.OK(c, bot)
}

// Create creates a new agent bot and auto-creates Permissible record.
// POST /platform/api/v1/agent_bots
// Reference: Chatwoot Platform::Api::V1::AgentBotsController#create
// Auto-permissible: PlatformApp automatically gets access to the created bot.
func (h *PlatformAgentBotHandler) Create(c *gin.Context) {
	platformAppID := getPlatformAppID(c)

	var req struct {
		Name        string          `json:"name" binding:"required"`
		Description string          `json:"description,omitempty"`
		AvatarURL   string          `json:"avatar_url,omitempty"`
		AccountID   *uint           `json:"account_id,omitempty"`
		Config      model.AgentBot  `json:"config,omitempty"` // Embedded struct for bot config
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}

	bot := &model.AgentBot{
		AccountID:   req.AccountID,
		Name:        req.Name,
		Description: req.Description,
		AvatarURL:   req.AvatarURL,
	}

	if err := h.agentBotRepo.Create(c.Request.Context(), bot); err != nil {
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, err.Error())
		return
	}

	// Auto-create Permissible
	perm := &model.Permissible{
		PlatformAppID:   platformAppID,
		PermissibleType: model.PermissibleTypeAgentBot,
		PermissibleID:   bot.ID,
	}
	if err := h.permissibleRepo.Create(c.Request.Context(), perm); err != nil {
		// Non-critical
	}

	response.Created(c, bot)
}

// Update updates an agent bot.
// PUT /platform/api/v1/agent_bots/:id
// Reference: Chatwoot Platform::Api::V1::AgentBotsController#update
// Requires: Permissible verification
func (h *PlatformAgentBotHandler) Update(c *gin.Context) {
	botID, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid bot ID")
		return
	}

	platformAppID := getPlatformAppID(c)

	// Verify Permissible access
	perm, err := h.permissibleRepo.FindByPlatformAppAndResource(c.Request.Context(), platformAppID, model.PermissibleTypeAgentBot, botID)
	if err != nil || perm == nil {
		response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden, "non permissible resource")
		return
	}

	bot, err := h.agentBotRepo.FindByID(c.Request.Context(), botID)
	if err != nil {
		response.AbortWithStatusError(c, http.StatusNotFound, response.ErrNotFound, "agent bot not found")
		return
	}

	var req struct {
		Name        string `json:"name,omitempty"`
		Description string `json:"description,omitempty"`
		AvatarURL   string `json:"avatar_url,omitempty"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, err.Error())
		return
	}

	if req.Name != "" {
		bot.Name = req.Name
	}
	if req.Description != "" {
		bot.Description = req.Description
	}
	if req.AvatarURL != "" {
		bot.AvatarURL = req.AvatarURL
	}

	if err := h.agentBotRepo.Update(c.Request.Context(), bot); err != nil {
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, err.Error())
		return
	}

	response.OK(c, bot)
}

// Destroy deletes an agent bot.
// DELETE /platform/api/v1/agent_bots/:id
// Reference: Chatwoot Platform::Api::V1::AgentBotsController#destroy
// Requires: Permissible verification
func (h *PlatformAgentBotHandler) Destroy(c *gin.Context) {
	botID, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid bot ID")
		return
	}

	platformAppID := getPlatformAppID(c)

	// Verify Permissible access
	perm, err := h.permissibleRepo.FindByPlatformAppAndResource(c.Request.Context(), platformAppID, model.PermissibleTypeAgentBot, botID)
	if err != nil || perm == nil {
		response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden, "non permissible resource")
		return
	}

	if err := h.agentBotRepo.Delete(c.Request.Context(), botID); err != nil {
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, err.Error())
		return
	}

	response.NoContent(c)
}

// DeleteAvatar removes the avatar of an agent bot.
// POST /platform/api/v1/agent_bots/:id/delete_avatar
// Reference: Chatwoot Platform::Api::V1::AgentBotsController#delete_avatar
// Requires: Permissible verification
func (h *PlatformAgentBotHandler) DeleteAvatar(c *gin.Context) {
	botID, err := parseUintParam(c, "id")
	if err != nil {
		response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid bot ID")
		return
	}

	platformAppID := getPlatformAppID(c)

	// Verify Permissible access
	perm, err := h.permissibleRepo.FindByPlatformAppAndResource(c.Request.Context(), platformAppID, model.PermissibleTypeAgentBot, botID)
	if err != nil || perm == nil {
		response.AbortWithStatusError(c, http.StatusForbidden, response.ErrForbidden, "non permissible resource")
		return
	}

	bot, err := h.agentBotRepo.FindByID(c.Request.Context(), botID)
	if err != nil {
		response.AbortWithStatusError(c, http.StatusNotFound, response.ErrNotFound, "agent bot not found")
		return
	}

	bot.AvatarURL = ""
	if err := h.agentBotRepo.Update(c.Request.Context(), bot); err != nil {
		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, err.Error())
		return
	}

	response.OK(c, bot)
}