// Text Adventure -- main loop (starter).
//
// Finish the TODOs so the game plays as described on the chapter page
// (project-04-text-adventure.html). As it is, the file runs: it prints
// placeholder lines, and quit stops it.
//
// When you need them, add "slices" to the import list.
//
// Run from this folder:
//   cd projects/04-text-adventure/starter
//   go run .

package main

import (
	"bufio"
	"fmt"
	"os"
	"strings"

	"textadventure/world"
)

var reader = bufio.NewReader(os.Stdin)
var currentRoom = world.StartID
var inventory = []string{}

// TODO: write describe so that it prints:
//
//	-- <name> --
//	<description>
//	Items here: <comma-separated items>     (only if the room has items)
//	Exits: <comma-separated exit names, in sorted order>
func describe(room int) {
	// Replace this placeholder line:
	fmt.Println("TODO: replace this line", room)
}

// TODO: write goTo so that it looks up the exit on the current room. If the
// exit exists, change currentRoom and describe the new room. Otherwise print
// "You cannot go that way."
func goTo(direction string) {
	// Replace this placeholder line:
	fmt.Println("TODO: replace this line", direction)
}

// TODO: write take so that it looks for itemName in the current room's items.
// If found, remove it from the room, add it to inventory, and print
// "You pick up the <item>." If not found, print "There is no <item> here."
// Return true if the player just picked up the gold coin, so that the main
// loop can end.
func take(itemName string) bool {
	// Replace this placeholder line:
	fmt.Println("TODO: replace this line", itemName)
	return false
}

// TODO: write showInventory so that it prints the items separated by commas.
// If there are none, print "You are carrying nothing."
func showInventory() {
	// Replace this placeholder line:
	fmt.Println("TODO: replace this line", inventory)
}

// readLine prints the prompt and gives back one trimmed line. The error is
// not nil when there is no more input.
func readLine(prompt string) (string, error) {
	fmt.Print(prompt)
	text, err := reader.ReadString('\n')
	line := strings.TrimSpace(text)
	if err != nil && line == "" {
		return "", err
	}
	return line, nil
}

// parse splits a typed line into a verb and an argument. Items like
// "gold coin" are two words, so everything after the verb is the argument.
func parse(line string) (string, string) {
	words := strings.Fields(line)
	if len(words) == 0 {
		return "", ""
	}
	return words[0], strings.Join(words[1:], " ")
}

func main() {
	describe(currentRoom)

	for {
		line, err := readLine("> ")
		if err != nil {
			fmt.Println()
			fmt.Println("Goodbye.")
			break
		}

		verb, arg := parse(line)

		if verb == "quit" {
			fmt.Println("Goodbye.")
			break
		}

		// TODO: send the other verbs to the right function: look, go, take,
		// inv. Leave the loop with break after take returns true. Use an if
		// chain, because break inside a switch would not leave the loop.
		// Replace this placeholder line:
		fmt.Println("TODO: replace this line", verb, arg)
	}
}