// SPDX-FileCopyrightText: Amolith <amolith@secluded.site>
//
// SPDX-License-Identifier: AGPL-3.0-or-later

package person

import (
	"encoding/json"
	"fmt"

	"git.secluded.site/go-lunatask"
	"git.secluded.site/lune/internal/client"
	"git.secluded.site/lune/internal/completion"
	"git.secluded.site/lune/internal/ui"
	"github.com/charmbracelet/lipgloss"
	"github.com/charmbracelet/lipgloss/table"
	"github.com/spf13/cobra"
)

// ListCmd lists people. Exported for potential use by shortcuts.
var ListCmd = &cobra.Command{
	Use:   "list",
	Short: "List people",
	Long: `List people from Lunatask.

Note: Due to end-to-end encryption, names are not available
through the API. Only metadata is shown.`,
	RunE: runList,
}

func init() {
	ListCmd.Flags().StringP("relationship", "r", "", "Filter by relationship strength")
	ListCmd.Flags().String("source", "", "Filter by source")
	ListCmd.Flags().String("source-id", "", "Filter by source ID")
	ListCmd.Flags().Bool("json", false, "Output as JSON")

	_ = ListCmd.RegisterFlagCompletionFunc("relationship", completion.Relationships)
}

func runList(cmd *cobra.Command, _ []string) error {
	apiClient, err := client.New()
	if err != nil {
		return err
	}

	opts := buildListOptions(cmd)

	people, err := ui.Spin("Fetching people…", func() ([]lunatask.Person, error) {
		return apiClient.ListPeople(cmd.Context(), opts)
	})
	if err != nil {
		return err
	}

	relFilter, _ := cmd.Flags().GetString("relationship")
	if relFilter != "" {
		people = filterByRelationship(people, relFilter)
	}

	if len(people) == 0 {
		fmt.Fprintln(cmd.OutOrStdout(), "No people found")

		return nil
	}

	if mustGetBoolFlag(cmd, "json") {
		return outputJSON(cmd, people)
	}

	return outputTable(cmd, people)
}

func buildListOptions(cmd *cobra.Command) *lunatask.ListPeopleOptions {
	source, _ := cmd.Flags().GetString("source")
	sourceID, _ := cmd.Flags().GetString("source-id")

	if source == "" && sourceID == "" {
		return nil
	}

	opts := &lunatask.ListPeopleOptions{}
	if source != "" {
		opts.Source = &source
	}

	if sourceID != "" {
		opts.SourceID = &sourceID
	}

	return opts
}

func filterByRelationship(people []lunatask.Person, rel string) []lunatask.Person {
	filtered := make([]lunatask.Person, 0, len(people))

	for _, person := range people {
		if person.RelationshipStrength != nil && string(*person.RelationshipStrength) == rel {
			filtered = append(filtered, person)
		}
	}

	return filtered
}

func mustGetBoolFlag(cmd *cobra.Command, name string) bool {
	f := cmd.Flags().Lookup(name)
	if f == nil {
		panic("flag not defined: " + name)
	}

	return f.Value.String() == "true"
}

func outputJSON(cmd *cobra.Command, people []lunatask.Person) error {
	enc := json.NewEncoder(cmd.OutOrStdout())
	enc.SetIndent("", "  ")

	if err := enc.Encode(people); err != nil {
		return fmt.Errorf("encoding JSON: %w", err)
	}

	return nil
}

func outputTable(cmd *cobra.Command, people []lunatask.Person) error {
	rows := make([][]string, 0, len(people))

	for _, person := range people {
		rel := "-"
		if person.RelationshipStrength != nil {
			rel = string(*person.RelationshipStrength)
		}

		created := ui.FormatDate(person.CreatedAt)

		rows = append(rows, []string{person.ID, rel, created})
	}

	tbl := table.New().
		Headers("ID", "RELATIONSHIP", "CREATED").
		Rows(rows...).
		StyleFunc(func(row, col int) lipgloss.Style {
			if row == table.HeaderRow {
				return ui.TableHeaderStyle()
			}

			return lipgloss.NewStyle()
		}).
		Border(ui.TableBorder())

	fmt.Fprintln(cmd.OutOrStdout(), tbl.Render())

	return nil
}