package cmd

import (
	"fmt"

	"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 RetryCmd(ctx *lmcli.Context) *cobra.Command {
	cmd := &cobra.Command{
		Use:   "retry <conversation>",
		Short: "Retry the last user reply in a conversation",
		Long:  `Prompt the conversation from the last user response.`,
		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 {
			err := validateGenerationFlags(ctx, cmd)
			if err != nil {
				return err
			}

			shortName := args[0]
			c := cmdutil.LookupConversation(ctx, shortName)

			// Load the complete thread from the root message
			messages, err := ctx.Conversations.PathToLeaf(c.SelectedRoot)
			if err != nil {
				return fmt.Errorf("Could not retrieve messages for conversation: %s", c.Title)
			}

			offset, _ := cmd.Flags().GetInt("offset")
			if offset < 0 {
				offset = -offset
			}

			if offset > len(messages)-1 {
				return fmt.Errorf("Offset %d is before the start of the conversation.", offset)
			}

			retryFromIdx := len(messages) - 1 - offset

			// decrease retryFromIdx until we hit a user message
			for retryFromIdx >= 0 && messages[retryFromIdx].Role != api.MessageRoleUser {
				retryFromIdx--
			}

			if messages[retryFromIdx].Role != api.MessageRoleUser {
				return fmt.Errorf("No user messages to retry")
			}

			fmt.Printf("Idx: %d Message: %v\n", retryFromIdx, messages[retryFromIdx])

			// Start a new branch at the last user message
			cmdutil.HandleReply(ctx, &messages[retryFromIdx], true)
			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.Conversations.ConversationShortNameCompletions(toComplete), compMode
		},
	}

	cmd.Flags().Int("offset", 0, "Offset from the last message to retry from.")

	applyGenerationFlags(ctx, cmd)
	return cmd
}