// Package plugins provides HTTP handlers for plugin management
package plugins

import (
	"encoding/json"
	"net/http"
	"time"

	"github.com/jfraeys/fetch_ml/internal/auth"
	"github.com/jfraeys/fetch_ml/internal/logging"
	"github.com/jfraeys/fetch_ml/internal/tracking"
)

// Handler provides plugin-related HTTP handlers
type Handler struct {
	logger   *logging.Logger
	registry *tracking.Registry
	config   map[string]PluginConfig // Plugin configurations
}

// PluginConfig represents the configuration for a plugin
type PluginConfig struct {
	Enabled      bool                   `json:"enabled"`
	Mode         string                 `json:"mode"` // sidecar, remote, disabled
	Image        string                 `json:"image,omitempty"`
	Settings     map[string]interface{} `json:"settings,omitempty"`
	LogBasePath  string                 `json:"log_base_path,omitempty"`
	ArtifactPath string                 `json:"artifact_path,omitempty"`
}

// PluginInfo represents plugin information returned by the API
type PluginInfo struct {
	Name            string       `json:"name"`
	Enabled         bool         `json:"enabled"`
	Mode            string       `json:"mode"`
	Status          string       `json:"status"` // healthy, unhealthy, starting, stopped
	Config          PluginConfig `json:"config"`
	RequiresRestart bool         `json:"requires_restart"`
	Version         string       `json:"version,omitempty"`
}

// PluginStatus represents the status of a plugin instance
type PluginStatus struct {
	Name      string    `json:"name"`
	Status    string    `json:"status"`
	URL       string    `json:"url,omitempty"`
	LastCheck time.Time `json:"last_check,omitempty"`
}

// NewHandler creates a new plugins handler
func NewHandler(
	logger *logging.Logger,
	registry *tracking.Registry,
	config map[string]PluginConfig,
) *Handler {
	return &Handler{
		logger:   logger,
		registry: registry,
		config:   config,
	}
}

// GetV1Plugins handles GET /v1/plugins
func (h *Handler) GetV1Plugins(w http.ResponseWriter, r *http.Request) {
	user := auth.GetUserFromContext(r.Context())
	if !h.checkPermission(user, "plugins:read") {
		http.Error(w, `{"error":"Insufficient permissions","code":"FORBIDDEN"}`, http.StatusForbidden)
		return
	}

	plugins := []PluginInfo{}

	// If registry is available, get plugin status
	if h.registry != nil {
		for name := range h.config {
			cfg := h.config[name]
			info := PluginInfo{
				Name:            name,
				Enabled:         cfg.Enabled,
				Mode:            cfg.Mode,
				Status:          "unknown",
				Config:          cfg,
				RequiresRestart: false,   // Default: plugins support hot-reload
				Version:         "1.0.0", // Placeholder
			}

			// Check if plugin is registered
			if plugin, ok := h.registry.Get(name); ok {
				// Check plugin health if available
				if cfg.Enabled && cfg.Mode != "disabled" {
					info.Status = "healthy" // Default, would check actual health
					_ = plugin              // Use plugin for actual health check
				}
			}

			plugins = append(plugins, info)
		}
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(plugins)
}

// GetV1PluginsPluginName handles GET /v1/plugins/{pluginName}
func (h *Handler) GetV1PluginsPluginName(w http.ResponseWriter, r *http.Request) {
	user := auth.GetUserFromContext(r.Context())
	if !h.checkPermission(user, "plugins:read") {
		http.Error(w, `{"error":"Insufficient permissions","code":"FORBIDDEN"}`, http.StatusForbidden)
		return
	}

	pluginName := r.PathValue("pluginName")
	if pluginName == "" {
		http.Error(w, `{"error":"Missing plugin name","code":"BAD_REQUEST"}`, http.StatusBadRequest)
		return
	}

	cfg, ok := h.config[pluginName]
	if !ok {
		http.Error(w, `{"error":"Plugin not found","code":"NOT_FOUND"}`, http.StatusNotFound)
		return
	}

	info := PluginInfo{
		Name:            pluginName,
		Enabled:         cfg.Enabled,
		Mode:            cfg.Mode,
		Status:          "unknown",
		Config:          cfg,
		RequiresRestart: false,
		Version:         "1.0.0",
	}

	if cfg.Enabled && cfg.Mode != "disabled" {
		info.Status = "healthy"
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(info)
}

// GetV1PluginsPluginNameConfig handles GET /v1/plugins/{pluginName}/config
func (h *Handler) GetV1PluginsPluginNameConfig(w http.ResponseWriter, r *http.Request) {
	user := auth.GetUserFromContext(r.Context())
	if !h.checkPermission(user, "plugins:read") {
		http.Error(w, `{"error":"Insufficient permissions","code":"FORBIDDEN"}`, http.StatusForbidden)
		return
	}

	pluginName := r.PathValue("pluginName")
	if pluginName == "" {
		http.Error(w, `{"error":"Missing plugin name","code":"BAD_REQUEST"}`, http.StatusBadRequest)
		return
	}

	cfg, ok := h.config[pluginName]
	if !ok {
		http.Error(w, `{"error":"Plugin not found","code":"NOT_FOUND"}`, http.StatusNotFound)
		return
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(cfg)
}

// PutV1PluginsPluginNameConfig handles PUT /v1/plugins/{pluginName}/config
func (h *Handler) PutV1PluginsPluginNameConfig(w http.ResponseWriter, r *http.Request) {
	user := auth.GetUserFromContext(r.Context())
	if !h.checkPermission(user, "plugins:write") {
		http.Error(w, `{"error":"Insufficient permissions","code":"FORBIDDEN"}`, http.StatusForbidden)
		return
	}

	pluginName := r.PathValue("pluginName")
	if pluginName == "" {
		http.Error(w, `{"error":"Missing plugin name","code":"BAD_REQUEST"}`, http.StatusBadRequest)
		return
	}

	var newConfig PluginConfig
	if err := json.NewDecoder(r.Body).Decode(&newConfig); err != nil {
		http.Error(w, `{"error":"Invalid request body","code":"BAD_REQUEST"}`, http.StatusBadRequest)
		return
	}

	// Update config
	h.config[pluginName] = newConfig
	h.logger.Info("updated plugin config", "plugin", pluginName, "user", user.Name)

	// Return updated plugin info
	info := PluginInfo{
		Name:            pluginName,
		Enabled:         newConfig.Enabled,
		Mode:            newConfig.Mode,
		Status:          "healthy",
		Config:          newConfig,
		RequiresRestart: false,
		Version:         "1.0.0",
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(info)
}

// DeleteV1PluginsPluginNameConfig handles DELETE /v1/plugins/{pluginName}/config
func (h *Handler) DeleteV1PluginsPluginNameConfig(w http.ResponseWriter, r *http.Request) {
	user := auth.GetUserFromContext(r.Context())
	if !h.checkPermission(user, "plugins:write") {
		http.Error(w, `{"error":"Insufficient permissions","code":"FORBIDDEN"}`, http.StatusForbidden)
		return
	}

	pluginName := r.PathValue("pluginName")
	if pluginName == "" {
		http.Error(w, `{"error":"Missing plugin name","code":"BAD_REQUEST"}`, http.StatusBadRequest)
		return
	}

	cfg, ok := h.config[pluginName]
	if !ok {
		http.Error(w, `{"error":"Plugin not found","code":"NOT_FOUND"}`, http.StatusNotFound)
		return
	}

	// Disable the plugin
	cfg.Enabled = false
	h.config[pluginName] = cfg

	h.logger.Info("disabled plugin", "plugin", pluginName, "user", user.Name)
	w.WriteHeader(http.StatusNoContent)
}

// GetV1PluginsPluginNameHealth handles GET /v1/plugins/{pluginName}/health
func (h *Handler) GetV1PluginsPluginNameHealth(w http.ResponseWriter, r *http.Request) {
	user := auth.GetUserFromContext(r.Context())
	if !h.checkPermission(user, "plugins:read") {
		http.Error(w, `{"error":"Insufficient permissions","code":"FORBIDDEN"}`, http.StatusForbidden)
		return
	}

	pluginName := r.PathValue("pluginName")
	if pluginName == "" {
		http.Error(w, `{"error":"Missing plugin name","code":"BAD_REQUEST"}`, http.StatusBadRequest)
		return
	}

	cfg, ok := h.config[pluginName]
	if !ok {
		http.Error(w, `{"error":"Plugin not found","code":"NOT_FOUND"}`, http.StatusNotFound)
		return
	}

	status := "healthy"
	if !cfg.Enabled || cfg.Mode == "disabled" {
		status = "stopped"
	}

	response := map[string]interface{}{
		"status":    status,
		"version":   "1.0.0",
		"timestamp": time.Now().UTC(),
	}

	w.Header().Set("Content-Type", "application/json")
	json.NewEncoder(w).Encode(response)
}

// checkPermission checks if the user has the required permission
func (h *Handler) checkPermission(user *auth.User, permission string) bool {
	if user == nil {
		return false
	}

	// Admin has all permissions
	for _, role := range user.Roles {
		if role == "admin" {
			return true
		}
	}

	// Check specific permission
	for perm, hasPerm := range user.Permissions {
		if hasPerm && perm == permission {
			return true
		}
	}

	return false
}