package commands

import (
	"slices"
	"strings"

	tea "github.com/charmbracelet/bubbletea/v2"
	"github.com/sst/opencode/pkg/client"
)

type ExecuteCommandMsg Command
type ExecuteCommandsMsg []Command
type CommandExecutedMsg Command

type Keybinding struct {
	RequiresLeader bool
	Key            string
}

func (k Keybinding) Matches(msg tea.KeyPressMsg, leader bool) bool {
	key := k.Key
	key = strings.TrimSpace(key)
	return key == msg.String() && (k.RequiresLeader == leader)
}

type CommandName string
type Command struct {
	Name        CommandName
	Description string
	Keybindings []Keybinding
	Trigger     string
}

func (c Command) Keys() []string {
	var keys []string
	for _, k := range c.Keybindings {
		keys = append(keys, k.Key)
	}
	return keys
}

type CommandRegistry map[CommandName]Command

func (r CommandRegistry) Sorted() []Command {
	var commands []Command
	for _, command := range r {
		commands = append(commands, command)
	}
	slices.SortFunc(commands, func(a, b Command) int {
		if a.Name == AppExitCommand {
			return 1
		}
		if b.Name == AppExitCommand {
			return -1
		}
		return strings.Compare(string(a.Name), string(b.Name))
	})
	return commands
}

func (r CommandRegistry) Matches(msg tea.KeyPressMsg, leader bool) []Command {
	var matched []Command
	for _, command := range r.Sorted() {
		if command.Matches(msg, leader) {
			matched = append(matched, command)
		}
	}
	return matched
}

const (
	AppHelpCommand              CommandName = "app_help"
	EditorOpenCommand           CommandName = "editor_open"
	SessionNewCommand           CommandName = "session_new"
	SessionListCommand          CommandName = "session_list"
	SessionShareCommand         CommandName = "session_share"
	SessionInterruptCommand     CommandName = "session_interrupt"
	SessionCompactCommand       CommandName = "session_compact"
	ToolDetailsCommand          CommandName = "tool_details"
	ModelListCommand            CommandName = "model_list"
	ThemeListCommand            CommandName = "theme_list"
	ProjectInitCommand          CommandName = "project_init"
	InputClearCommand           CommandName = "input_clear"
	InputPasteCommand           CommandName = "input_paste"
	InputSubmitCommand          CommandName = "input_submit"
	InputNewlineCommand         CommandName = "input_newline"
	HistoryPreviousCommand      CommandName = "history_previous"
	HistoryNextCommand          CommandName = "history_next"
	MessagesPageUpCommand       CommandName = "messages_page_up"
	MessagesPageDownCommand     CommandName = "messages_page_down"
	MessagesHalfPageUpCommand   CommandName = "messages_half_page_up"
	MessagesHalfPageDownCommand CommandName = "messages_half_page_down"
	MessagesPreviousCommand     CommandName = "messages_previous"
	MessagesNextCommand         CommandName = "messages_next"
	MessagesFirstCommand        CommandName = "messages_first"
	MessagesLastCommand         CommandName = "messages_last"
	AppExitCommand              CommandName = "app_exit"
)

func (k Command) Matches(msg tea.KeyPressMsg, leader bool) bool {
	for _, binding := range k.Keybindings {
		if binding.Matches(msg, leader) {
			return true
		}
	}
	return false
}

func (k Command) FromConfig(config *client.ConfigInfo) Command {
	if config.Keybinds == nil {
		return k
	}
	keybinds := *config.Keybinds
	if keybind, ok := keybinds[string(k.Name)]; ok {
		k.Keybindings = parseBindings(keybind)
	}
	return k
}

func parseBindings(bindings ...string) []Keybinding {
	var parsedBindings []Keybinding
	for _, binding := range bindings {
		for p := range strings.SplitSeq(binding, ",") {
			requireLeader := strings.HasPrefix(p, "<leader>")
			keybinding := strings.ReplaceAll(p, "<leader>", "")
			keybinding = strings.TrimSpace(keybinding)
			parsedBindings = append(parsedBindings, Keybinding{
				RequiresLeader: requireLeader,
				Key:            keybinding,
			})
		}
	}
	return parsedBindings
}

func LoadFromConfig(config *client.ConfigInfo) CommandRegistry {
	defaults := []Command{
		{
			Name:        AppHelpCommand,
			Description: "show help",
			Keybindings: parseBindings("<leader>h"),
			Trigger:     "help",
		},
		{
			Name:        EditorOpenCommand,
			Description: "open editor",
			Keybindings: parseBindings("<leader>e"),
			Trigger:     "editor",
		},
		{
			Name:        SessionNewCommand,
			Description: "new session",
			Keybindings: parseBindings("<leader>n"),
			Trigger:     "new",
		},
		{
			Name:        SessionListCommand,
			Description: "list sessions",
			Keybindings: parseBindings("<leader>l"),
			Trigger:     "sessions",
		},
		{
			Name:        SessionShareCommand,
			Description: "share session",
			Keybindings: parseBindings("<leader>s"),
			Trigger:     "share",
		},
		{
			Name:        SessionInterruptCommand,
			Description: "interrupt session",
			Keybindings: parseBindings("esc"),
		},
		{
			Name:        SessionCompactCommand,
			Description: "compact the session",
			Keybindings: parseBindings("<leader>c"),
			Trigger:     "compact",
		},
		{
			Name:        ToolDetailsCommand,
			Description: "toggle tool details",
			Keybindings: parseBindings("<leader>d"),
			Trigger:     "details",
		},
		{
			Name:        ModelListCommand,
			Description: "list models",
			Keybindings: parseBindings("<leader>m"),
			Trigger:     "models",
		},
		{
			Name:        ThemeListCommand,
			Description: "list themes",
			Keybindings: parseBindings("<leader>t"),
			Trigger:     "themes",
		},
		{
			Name:        ProjectInitCommand,
			Description: "create or update AGENTS.md",
			Keybindings: parseBindings("<leader>i"),
			Trigger:     "init",
		},
		{
			Name:        InputClearCommand,
			Description: "clear input",
			Keybindings: parseBindings("ctrl+c"),
		},
		{
			Name:        InputPasteCommand,
			Description: "paste content",
			Keybindings: parseBindings("ctrl+v"),
		},
		{
			Name:        InputSubmitCommand,
			Description: "submit message",
			Keybindings: parseBindings("enter"),
		},
		{
			Name:        InputNewlineCommand,
			Description: "insert newline",
			Keybindings: parseBindings("shift+enter"),
		},
		{
			Name:        HistoryPreviousCommand,
			Description: "previous prompt",
			Keybindings: parseBindings("up"),
		},
		{
			Name:        HistoryNextCommand,
			Description: "next prompt",
			Keybindings: parseBindings("down"),
		},
		{
			Name:        MessagesPageUpCommand,
			Description: "page up",
			Keybindings: parseBindings("pgup"),
		},
		{
			Name:        MessagesPageDownCommand,
			Description: "page down",
			Keybindings: parseBindings("pgdown"),
		},
		{
			Name:        MessagesHalfPageUpCommand,
			Description: "half page up",
			Keybindings: parseBindings("ctrl+alt+u"),
		},
		{
			Name:        MessagesHalfPageDownCommand,
			Description: "half page down",
			Keybindings: parseBindings("ctrl+alt+d"),
		},
		{
			Name:        MessagesPreviousCommand,
			Description: "previous message",
			Keybindings: parseBindings("ctrl+alt+k"),
		},
		{
			Name:        MessagesNextCommand,
			Description: "next message",
			Keybindings: parseBindings("ctrl+alt+j"),
		},
		{
			Name:        MessagesFirstCommand,
			Description: "first message",
			Keybindings: parseBindings("ctrl+g"),
		},
		{
			Name:        MessagesLastCommand,
			Description: "last message",
			Keybindings: parseBindings("ctrl+alt+g"),
		},
		{
			Name:        AppExitCommand,
			Description: "exit the app",
			Keybindings: parseBindings("ctrl+c", "<leader>q"),
			Trigger:     "exit",
		},
	}
	registry := make(CommandRegistry)
	for _, command := range defaults {
		registry[command.Name] = command.FromConfig(config)
	}
	return registry
}
