package cmd

import (
	"fmt"
	"strings"

	"git.mlow.ca/mlow/lmcli/pkg/api"
	cmdutil "git.mlow.ca/mlow/lmcli/pkg/cmd/util"
	"git.mlow.ca/mlow/lmcli/pkg/lmcli"
	"github.com/spf13/cobra"
)

func ContinueCmd(ctx *lmcli.Context) *cobra.Command {
	cmd := &cobra.Command{
		Use:   "continue <conversation>",
		Short: "Continue a conversation from the last message",
		Long:  `Re-prompt the conversation with all existing prompts. Useful if a reply was cut short.`,
		Args: func(cmd *cobra.Command, args []string) error {
			argCount := 1
			if err := cobra.MinimumNArgs(argCount)(cmd, args); err != nil {
				return err
			}
			return nil
		},
		RunE: func(cmd *cobra.Command, args []string) error {
			shortName := args[0]
			conversation := cmdutil.LookupConversation(ctx, shortName)

			messages, err := ctx.Store.PathToLeaf(conversation.SelectedRoot)
			if err != nil {
				return fmt.Errorf("could not retrieve conversation messages: %v", err)
			}

			if len(messages) < 2 {
				return fmt.Errorf("conversation expected to have at least 2 messages")
			}

			lastMessage := &messages[len(messages)-1]
			if lastMessage.Role != api.MessageRoleAssistant {
				return fmt.Errorf("the last message in the conversation is not an assistant message")
			}

			// Output the contents of the last message so far
			fmt.Print(lastMessage.Content)

			// Submit the LLM request, allowing it to continue the last message
			continuedOutput, err := cmdutil.Prompt(ctx, messages, nil)
			if err != nil {
				return fmt.Errorf("error fetching LLM response: %v", err)
			}

			// Append the new response to the original message
			lastMessage.Content += strings.TrimRight(continuedOutput.Content, "\n\t ")

			// Update the original message
			err = ctx.Store.UpdateMessage(lastMessage)
			if err != nil {
				return fmt.Errorf("could not update the last message: %v", err)
			}

			return nil
		},
		ValidArgsFunction: func(cmd *cobra.Command, args []string, toComplete string) ([]string, cobra.ShellCompDirective) {
			compMode := cobra.ShellCompDirectiveNoFileComp
			if len(args) != 0 {
				return nil, compMode
			}
			return ctx.Store.ConversationShortNameCompletions(toComplete), compMode
		},
	}
	applyPromptFlags(ctx, cmd)
	return cmd
}