package cmd

import (
	"context"
	"encoding/json"
	"fmt"
	"os"
	"strings"

	"gogs.dmsc.dev/arp/arp_cli/client"
	"gogs.dmsc.dev/arp/arp_cli/config"

	"github.com/AlecAivazis/survey/v2"
	"github.com/olekukonko/tablewriter"
	"github.com/urfave/cli/v3"
)

// ChannelCommand returns the channel command
func ChannelCommand() *cli.Command {
	return &cli.Command{
		Name:  "channel",
		Usage: "Manage channels",
		Description: `Manage ARP channels. Channels are chat conversations between users/agents.

Use this command to create, list, update, and delete channels.`,
		Commands: []*cli.Command{
			{
				Name:    "list",
				Aliases: []string{"ls"},
				Usage:   "List all channels",
				Flags: []cli.Flag{
					&cli.BoolFlag{
						Name:    "json",
						Aliases: []string{"j"},
						Usage:   "Output as JSON",
					},
				},
				Action: channelList,
			},
			{
				Name:  "get",
				Usage: "Get a channel by ID",
				Flags: []cli.Flag{
					&cli.StringFlag{
						Name:     "id",
						Aliases:  []string{"i"},
						Usage:    "Channel ID",
						Required: true,
					},
					&cli.BoolFlag{
						Name:    "json",
						Aliases: []string{"j"},
						Usage:   "Output as JSON",
					},
				},
				Action: channelGet,
			},
			{
				Name:   "create",
				Usage:  "Create a new channel",
				Action: channelCreate,
				Flags: []cli.Flag{
					&cli.StringSliceFlag{
						Name:    "participants",
						Aliases: []string{"p"},
						Usage:   "Participant user IDs",
					},
				},
			},
			{
				Name:   "update",
				Usage:  "Update a channel",
				Action: channelUpdate,
				Flags: []cli.Flag{
					&cli.StringFlag{
						Name:     "id",
						Aliases:  []string{"i"},
						Usage:    "Channel ID",
						Required: true,
					},
					&cli.StringSliceFlag{
						Name:    "participants",
						Aliases: []string{"p"},
						Usage:   "Participant user IDs",
					},
				},
			},
			{
				Name:   "delete",
				Usage:  "Delete a channel",
				Action: channelDelete,
				Flags: []cli.Flag{
					&cli.StringFlag{
						Name:     "id",
						Aliases:  []string{"i"},
						Usage:    "Channel ID",
						Required: true,
					},
					&cli.BoolFlag{
						Name:    "yes",
						Aliases: []string{"y"},
						Usage:   "Skip confirmation",
					},
				},
			},
		},
	}
}

type Channel struct {
	ID           string `json:"id"`
	Participants []struct {
		ID    string `json:"id"`
		Email string `json:"email"`
	} `json:"participants"`
	CreatedAt string `json:"createdAt"`
	UpdatedAt string `json:"updatedAt"`
}

func channelList(ctx context.Context, cmd *cli.Command) error {
	cfg, err := config.Load()
	if err != nil {
		return err
	}
	if err := RequireAuth(cfg); err != nil {
		return err
	}

	c := client.New(cfg.ServerURL)
	c.SetToken(cfg.Token)

	query := "query Channels { channels { id participants { id email } createdAt updatedAt } }"

	resp, err := c.Query(query, nil)
	if err != nil {
		return err
	}

	var result struct {
		Channels []Channel `json:"channels"`
	}
	if err := json.Unmarshal(resp.Data, &result); err != nil {
		return err
	}

	if cmd.Bool("json") {
		enc := json.NewEncoder(os.Stdout)
		enc.SetIndent("", "  ")
		return enc.Encode(result.Channels)
	}

	if len(result.Channels) == 0 {
		fmt.Println("No channels found.")
		return nil
	}

	table := tablewriter.NewWriter(os.Stdout)
	table.Header([]string{"ID", "Participants", "Created At"})
	

	for _, ch := range result.Channels {
		participants := make([]string, len(ch.Participants))
		for i, p := range ch.Participants {
			participants[i] = p.Email
		}
		table.Append([]string{ch.ID, strings.Join(participants, ", "), ch.CreatedAt})
	}

	table.Render()
	return nil
}

func channelGet(ctx context.Context, cmd *cli.Command) error {
	cfg, err := config.Load()
	if err != nil {
		return err
	}
	if err := RequireAuth(cfg); err != nil {
		return err
	}

	c := client.New(cfg.ServerURL)
	c.SetToken(cfg.Token)

	id := cmd.String("id")
	query := "query Channel($id: ID!) { channel(id: $id) { id participants { id email } createdAt updatedAt } }"

	resp, err := c.Query(query, map[string]interface{}{"id": id})
	if err != nil {
		return err
	}

	var result struct {
		Channel *Channel `json:"channel"`
	}
	if err := json.Unmarshal(resp.Data, &result); err != nil {
		return err
	}

	if result.Channel == nil {
		return fmt.Errorf("channel not found")
	}

	if cmd.Bool("json") {
		enc := json.NewEncoder(os.Stdout)
		enc.SetIndent("", "  ")
		return enc.Encode(result.Channel)
	}

	ch := result.Channel
	fmt.Printf("ID: %s\n", ch.ID)
	fmt.Printf("Participants:\n")
	for _, p := range ch.Participants {
		fmt.Printf("  - %s (%s)\n", p.Email, p.ID)
	}
	fmt.Printf("Created At: %s\n", ch.CreatedAt)
	fmt.Printf("Updated At: %s\n", ch.UpdatedAt)

	return nil
}

func channelCreate(ctx context.Context, cmd *cli.Command) error {
	cfg, err := config.Load()
	if err != nil {
		return err
	}
	if err := RequireAuth(cfg); err != nil {
		return err
	}

	participants := cmd.StringSlice("participants")

	if len(participants) == 0 {
		var participantsStr string
		prompt := &survey.Input{Message: "Participant user IDs (comma-separated):"}
		if err := survey.AskOne(prompt, &participantsStr, survey.WithValidator(survey.Required)); err != nil {
			return err
		}
		for _, p := range strings.Split(participantsStr, ",") {
			participants = append(participants, strings.TrimSpace(p))
		}
	}

	c := client.New(cfg.ServerURL)
	c.SetToken(cfg.Token)

	mutation := `mutation CreateChannel($input: NewChannel!) { createChannel(input: $input) { id participants { id email } createdAt updatedAt } }`

	input := map[string]interface{}{
		"participants": participants,
	}

	resp, err := c.Mutation(mutation, map[string]interface{}{"input": input})
	if err != nil {
		return err
	}

	var result struct {
		CreateChannel *Channel `json:"createChannel"`
	}
	if err := json.Unmarshal(resp.Data, &result); err != nil {
		return err
	}

	if result.CreateChannel == nil {
		return fmt.Errorf("failed to create channel")
	}

	fmt.Printf("Channel created successfully!\n")
	fmt.Printf("ID: %s\n", result.CreateChannel.ID)

	return nil
}

func channelUpdate(ctx context.Context, cmd *cli.Command) error {
	cfg, err := config.Load()
	if err != nil {
		return err
	}
	if err := RequireAuth(cfg); err != nil {
		return err
	}

	id := cmd.String("id")
	participants := cmd.StringSlice("participants")

	if len(participants) == 0 {
		fmt.Println("No updates provided. Use flags to specify what to update.")
		return nil
	}

	c := client.New(cfg.ServerURL)
	c.SetToken(cfg.Token)

	input := map[string]interface{}{
		"participants": participants,
	}

	mutation := `mutation UpdateChannel($id: ID!, $input: UpdateChannelInput!) { updateChannel(id: $id, input: $input) { id participants { id email } createdAt updatedAt } }`

	resp, err := c.Mutation(mutation, map[string]interface{}{"id": id, "input": input})
	if err != nil {
		return err
	}

	var result struct {
		UpdateChannel *Channel `json:"updateChannel"`
	}
	if err := json.Unmarshal(resp.Data, &result); err != nil {
		return err
	}

	if result.UpdateChannel == nil {
		return fmt.Errorf("channel not found")
	}

	fmt.Printf("Channel updated successfully!\n")
	fmt.Printf("ID: %s\n", result.UpdateChannel.ID)

	return nil
}

func channelDelete(ctx context.Context, cmd *cli.Command) error {
	cfg, err := config.Load()
	if err != nil {
		return err
	}
	if err := RequireAuth(cfg); err != nil {
		return err
	}

	id := cmd.String("id")
	skipConfirm := cmd.Bool("yes")

	if !skipConfirm {
		confirm := false
		prompt := &survey.Confirm{
			Message: fmt.Sprintf("Are you sure you want to delete channel %s?", id),
			Default: false,
		}
		if err := survey.AskOne(prompt, &confirm); err != nil {
			return err
		}
		if !confirm {
			fmt.Println("Deletion cancelled.")
			return nil
		}
	}

	c := client.New(cfg.ServerURL)
	c.SetToken(cfg.Token)

	mutation := `mutation DeleteChannel($id: ID!) { deleteChannel(id: $id) }`

	resp, err := c.Mutation(mutation, map[string]interface{}{"id": id})
	if err != nil {
		return err
	}

	var result struct {
		DeleteChannel bool `json:"deleteChannel"`
	}
	if err := json.Unmarshal(resp.Data, &result); err != nil {
		return err
	}

	if result.DeleteChannel {
		fmt.Printf("Channel %s deleted successfully.\n", id)
	} else {
		fmt.Printf("Failed to delete channel %s.\n", id)
	}

	return nil
}