package adventure

import (
	"context"
	"errors"
	"fmt"
	"io"
	"strings"
	"time"

	"git.t-juice.club/torjus/oubliette/internal/shell"
)

const sessionTimeout = 10 * time.Minute

// AdventureShell implements a Zork-style text adventure set in a dungeon/data center.
type AdventureShell struct{}

// NewAdventureShell returns a new AdventureShell instance.
func NewAdventureShell() *AdventureShell {
	return &AdventureShell{}
}

func (a *AdventureShell) Name() string        { return "adventure" }
func (a *AdventureShell) Description() string { return "Zork-style text adventure dungeon crawler" }

func (a *AdventureShell) Handle(ctx context.Context, sess *shell.SessionContext, rw io.ReadWriteCloser) error {
	ctx, cancel := context.WithTimeout(ctx, sessionTimeout)
	defer cancel()

	dungeonName := configString(sess.ShellConfig, "dungeon_name", "THE OUBLIETTE")
	game := newGame()

	// Print banner and initial room.
	banner := strings.ReplaceAll(adventureBanner(dungeonName), "\n", "\r\n")
	fmt.Fprint(rw, banner)

	// Show starting room.
	startDesc := game.describeRoom(game.rooms[game.currentRoom])
	startDesc = strings.ReplaceAll(startDesc, "\n", "\r\n")
	fmt.Fprintf(rw, "%s\r\n\r\n", startDesc)

	for {
		if _, err := fmt.Fprint(rw, "> "); err != nil {
			return nil
		}

		line, err := shell.ReadLine(ctx, rw)
		if errors.Is(err, io.EOF) {
			fmt.Fprint(rw, "\r\n")
			return nil
		}
		if err != nil {
			return nil
		}

		trimmed := strings.TrimSpace(line)
		if trimmed == "" {
			continue
		}

		result := game.dispatch(trimmed)

		var output string
		if result.output != "" {
			output = result.output
			output = strings.ReplaceAll(output, "\r\n", "\n")
			output = strings.ReplaceAll(output, "\n", "\r\n")
			fmt.Fprintf(rw, "%s\r\n", output)
		}

		// Log command and output to store.
		if sess.Store != nil {
			if err := sess.Store.AppendSessionLog(ctx, sess.SessionID, trimmed, output); err != nil {
				return fmt.Errorf("append session log: %w", err)
			}
		}
		if sess.OnCommand != nil {
			sess.OnCommand("adventure")
		}

		if result.exit {
			return nil
		}
	}
}

func adventureBanner(dungeonName string) string {
	return fmt.Sprintf(`
  ___  _   _ ____  _     ___ _____ _____ _____
 / _ \| | | | __ )| |   |_ _| ____|_   _|_   _| ___
| | | | | | |  _ \| |    | ||  _|   | |   | |  / _ \
| |_| | |_| | |_) | |___ | || |___  | |   | | |  __/
 \___/ \___/|____/|_____|___|_____| |_|   |_|  \___|

Welcome to %s.

You wake up in the dark. The air is cold and hums with electricity.
This is a place where things are put to be forgotten.

Type 'help' for commands. Type 'look' to examine your surroundings.

`, dungeonName)
}

// configString reads a string from the shell config map with a default.
func configString(cfg map[string]any, key, defaultVal string) string {
	if cfg == nil {
		return defaultVal
	}
	if v, ok := cfg[key]; ok {
		if s, ok := v.(string); ok && s != "" {
			return s
		}
	}
	return defaultVal
}