package handler

import (
	"fmt"
	"net/http"

	"github.com/go-chi/chi/v5"

	"github.com/anotherhadi/iknowyou/internal/respond"
	"github.com/anotherhadi/iknowyou/internal/tools"
)

type ToolsHandler struct {
	factories []func() tools.ToolRunner
}

func NewToolsHandler(factories []func() tools.ToolRunner) *ToolsHandler {
	return &ToolsHandler{factories: factories}
}

type toolInfo struct {
	Name              string              `json:"name"`
	Description       string              `json:"description"`
	Link              string              `json:"link,omitempty"`
	Icon              string              `json:"icon,omitempty"`
	InputTypes        []tools.InputType   `json:"input_types"`
	Configurable      bool                `json:"configurable"`
	ConfigFields      []tools.ConfigField `json:"config_fields,omitempty"`
	Available         *bool               `json:"available,omitempty"`
	UnavailableReason string              `json:"unavailable_reason,omitempty"`
	Dependencies      []string            `json:"dependencies,omitempty"`
}

func toToolInfo(t tools.ToolRunner) toolInfo {
	_, configurable := t.(tools.Configurable)

	var fields []tools.ConfigField
	if d, ok := t.(tools.ConfigDescriber); ok {
		fields = d.ConfigFields()
	}

	var available *bool
	var unavailableReason string
	if checker, ok := t.(tools.AvailabilityChecker); ok {
		avail, reason := checker.Available()
		available = &avail
		if !avail {
			unavailableReason = reason
		}
	}

	var dependencies []string
	if lister, ok := t.(tools.DependencyLister); ok {
		dependencies = lister.Dependencies()
	}

	return toolInfo{
		Name:              t.Name(),
		Description:       t.Description(),
		Link:              t.Link(),
		Icon:              t.Icon(),
		InputTypes:        t.InputTypes(),
		Configurable:      configurable,
		ConfigFields:      fields,
		Available:         available,
		UnavailableReason: unavailableReason,
		Dependencies:      dependencies,
	}
}

// GET /api/tools
func (h *ToolsHandler) List(w http.ResponseWriter, r *http.Request) {
	infos := make([]toolInfo, 0, len(h.factories))
	for _, factory := range h.factories {
		infos = append(infos, toToolInfo(factory()))
	}
	respond.JSON(w, http.StatusOK, infos)
}

// GET /api/tools/{name}
func (h *ToolsHandler) Get(w http.ResponseWriter, r *http.Request) {
	name := chi.URLParam(r, "name")
	for _, factory := range h.factories {
		t := factory()
		if t.Name() == name {
			respond.JSON(w, http.StatusOK, toToolInfo(t))
			return
		}
	}
	respond.Error(w, http.StatusNotFound, fmt.Sprintf("tool %q not found", name))
}