package llamactl

import (
	"encoding/json"
	"fmt"
	"net/http"
	"os/exec"

	"github.com/go-chi/chi/v5"
	"github.com/google/uuid"
)

type Handler struct {
	InstanceManager InstanceManager
}

func NewHandler(im InstanceManager) *Handler {
	return &Handler{
		InstanceManager: im,
	}
}

// HelpHandler godoc
// @Summary Get help for llama server
// @Description Returns the help text for the llama server command
// @Tags server
// #Produces text/plain
// @Success 200 {string} string "Help text"
// @Failure 500 {string} string "Internal Server Error"
// @Router /server/help [get]
func (h *Handler) HelpHandler() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		helpCmd := exec.Command("llama-server", "--help")
		output, err := helpCmd.CombinedOutput()
		if err != nil {
			http.Error(w, "Failed to get help: "+err.Error(), http.StatusInternalServerError)
			return
		}
		w.Header().Set("Content-Type", "text/plain")
		w.Write(output)
	}
}

// VersionHandler godoc
// @Summary Get version of llama server
// @Description Returns the version of the llama server command
// @Tags server
// #Produces text/plain
// @Success 200 {string} string "Version information"
// @Failure 500 {string} string "Internal Server Error"
// @Router /server/version [get]
func (h *Handler) VersionHandler() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		versionCmd := exec.Command("llama-server", "--version")
		output, err := versionCmd.CombinedOutput()
		if err != nil {
			http.Error(w, "Failed to get version: "+err.Error(), http.StatusInternalServerError)
			return
		}
		w.Header().Set("Content-Type", "text/plain")
		w.Write(output)
	}
}

// ListDevicesHandler godoc
// @Summary List available devices for llama server
// @Description Returns a list of available devices for the llama server
// @Tags server
// #Produces text/plain
// @Success 200 {string} string "List of devices"
// @Failure 500 {string} string "Internal Server Error"
// @Router /server/devices [get]
func (h *Handler) ListDevicesHandler() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		listCmd := exec.Command("llama-server", "--list-devices")
		output, err := listCmd.CombinedOutput()
		if err != nil {
			http.Error(w, "Failed to list devices: "+err.Error(), http.StatusInternalServerError)
			return
		}
		w.Header().Set("Content-Type", "text/plain")
		w.Write(output)
	}
}

func (h *Handler) StartHandler() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var requestBody InstanceOptions
		if err := json.NewDecoder(r.Body).Decode(&requestBody); err != nil {
			fmt.Println("Error decoding request body:", err)
			http.Error(w, "Invalid request body", http.StatusBadRequest)
			return
		}

	}
}

func (h *Handler) GetInstance() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		id := chi.URLParam(r, "id")
		uuid, err := uuid.Parse(id)
		if err != nil {
			http.Error(w, "Invalid UUID format", http.StatusBadRequest)
			return
		}

		instance, err := h.InstanceManager.GetInstance(uuid)
		if err != nil {
			http.Error(w, "Failed to get instance: "+err.Error(), http.StatusInternalServerError)
			return
		}

		w.Header().Set("Content-Type", "application/json")
		if err := json.NewEncoder(w).Encode(instance); err != nil {
			http.Error(w, "Failed to encode instance: "+err.Error(), http.StatusInternalServerError)
			return
		}
	}
}

func (h *Handler) UpdateInstance() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		id := chi.URLParam(r, "id")
		uuid, err := uuid.Parse(id)
		if err != nil {
			http.Error(w, "Invalid UUID format", http.StatusBadRequest)
			return
		}

		var options InstanceOptions
		if err := json.NewDecoder(r.Body).Decode(&options); err != nil {
			http.Error(w, "Invalid request body", http.StatusBadRequest)
			return
		}

		instance, err := h.InstanceManager.UpdateInstance(uuid, &options)
		if err != nil {
			http.Error(w, "Failed to update instance: "+err.Error(), http.StatusInternalServerError)
			return
		}

		instance, err = h.InstanceManager.RestartInstance(uuid)
		if err != nil {
			http.Error(w, "Failed to restart instance: "+err.Error(), http.StatusInternalServerError)
			return
		}

		w.Header().Set("Content-Type", "application/json")
		if err := json.NewEncoder(w).Encode(instance); err != nil {
			http.Error(w, "Failed to encode instance: "+err.Error(), http.StatusInternalServerError)
			return
		}
	}
}

func (h *Handler) StartInstance() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		id := chi.URLParam(r, "id")
		uuid, err := uuid.Parse(id)
		if err != nil {
			http.Error(w, "Invalid UUID format", http.StatusBadRequest)
			return
		}

		instance, err := h.InstanceManager.StartInstance(uuid)
		if err != nil {
			http.Error(w, "Failed to start instance: "+err.Error(), http.StatusInternalServerError)
			return
		}

		w.Header().Set("Content-Type", "application/json")
		if err := json.NewEncoder(w).Encode(instance); err != nil {
			http.Error(w, "Failed to encode instance: "+err.Error(), http.StatusInternalServerError)
			return
		}
	}
}

func (h *Handler) StopInstance() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		id := chi.URLParam(r, "id")
		uuid, err := uuid.Parse(id)
		if err != nil {
			http.Error(w, "Invalid UUID format", http.StatusBadRequest)
			return
		}

		instance, err := h.InstanceManager.StopInstance(uuid)
		if err != nil {
			http.Error(w, "Failed to stop instance: "+err.Error(), http.StatusInternalServerError)
			return
		}

		w.Header().Set("Content-Type", "application/json")
		if err := json.NewEncoder(w).Encode(instance); err != nil {
			http.Error(w, "Failed to encode instance: "+err.Error(), http.StatusInternalServerError)
			return
		}
	}
}

func (h *Handler) RestartInstance() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		id := chi.URLParam(r, "id")
		uuid, err := uuid.Parse(id)
		if err != nil {
			http.Error(w, "Invalid UUID format", http.StatusBadRequest)
			return
		}

		instance, err := h.InstanceManager.RestartInstance(uuid)
		if err != nil {
			http.Error(w, "Failed to restart instance: "+err.Error(), http.StatusInternalServerError)
			return
		}

		w.Header().Set("Content-Type", "application/json")
		if err := json.NewEncoder(w).Encode(instance); err != nil {
			http.Error(w, "Failed to encode instance: "+err.Error(), http.StatusInternalServerError)
			return
		}
	}
}