package client

import (
	"fmt"
	"net/http"
	"net/url"

	"task/internal/command"
	"task/internal/ticket"
)

// Executor implements command.Executor via daemon mutation endpoints.
type Executor struct{ c *Client }

func (c *Client) Executor() *Executor { return &Executor{c: c} }

func (e *Executor) Do(cmd command.Command) error {
	switch c := cmd.(type) {
	case *command.CreateTicket:
		var out ticket.Ticket
		if err := e.c.do(http.MethodPost, "/v1/tickets", c.Ticket, &out); err != nil {
			return err
		}
		c.Ticket = out
		return nil
	case *command.UpdateTicket:
		return e.c.do(http.MethodPatch, "/v1/tickets/"+url.PathEscape(c.After.ID), c.After, nil)
	case *command.DeleteTicket:
		return e.c.do(http.MethodDelete, "/v1/tickets/"+url.PathEscape(c.Snapshot.ID), nil, nil)
	case *command.MoveTicket:
		var out ticket.Ticket
		if err := e.c.do(http.MethodPost, "/v1/tickets/"+url.PathEscape(c.Before.ID)+"/move", map[string]string{
			"toProjectId": c.After.ProjectID,
		}, &out); err != nil {
			return err
		}
		c.After = out
		return nil
	case *command.AddTimeEntry:
		var out ticket.TimeEntry
		if err := e.c.do(http.MethodPost, "/v1/time", c.Entry, &out); err != nil {
			return err
		}
		c.Entry = out
		return nil
	case *command.RemoveTimeEntry:
		return e.c.do(http.MethodDelete, "/v1/time/"+url.PathEscape(c.Snapshot.ID), nil, nil)
	case *command.UpdateTimeEntry:
		return e.c.do(http.MethodPatch, "/v1/time/"+url.PathEscape(c.After.ID), c.After, nil)
	default:
		return fmt.Errorf("unsupported command type %T", cmd)
	}
}

func (e *Executor) Undo() error {
	return e.c.do(http.MethodPost, "/v1/undo", map[string]any{}, nil)
}

func (e *Executor) Redo() error {
	return e.c.do(http.MethodPost, "/v1/redo", map[string]any{}, nil)
}

func (e *Executor) CanUndo() bool {
	st, err := e.status()
	if err != nil {
		return false
	}
	return st.CanUndo
}

func (e *Executor) CanRedo() bool {
	st, err := e.status()
	if err != nil {
		return false
	}
	return st.CanRedo
}

func (e *Executor) LastUndoName() string {
	st, _ := e.status()
	return st.LastUndoName
}

func (e *Executor) LastRedoName() string {
	st, _ := e.status()
	return st.LastRedoName
}

type historyStatus struct {
	CanUndo      bool   `json:"canUndo"`
	CanRedo      bool   `json:"canRedo"`
	LastUndoName string `json:"lastUndoName"`
	LastRedoName string `json:"lastRedoName"`
}

func (e *Executor) status() (historyStatus, error) {
	var st historyStatus
	err := e.c.do(http.MethodGet, "/v1/history", nil, &st)
	return st, err
}