// Copyright 2026 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT

package app

import (
	"errors"
	"fmt"
	"strings"

	"gitea.dev/tea/internal/clierr"
	"gitea.dev/tea/internal/services"
	"gitea.dev/tea/internal/settings"
	"gitea.dev/tea/internal/terminal"
	"github.com/spf13/cobra"
)

// repositoryArguments documents the [<repository>] argument of repository commands.
const repositoryArguments = `A repository can be supplied as NAME (one of yours), OWNER/NAME, HOST/OWNER/NAME or a URL.
Without an argument, the repository of the current Git clone is used.`

// repositoryArgument selects the repository from an optional positional owner/name or URL.
func (a *application) repositoryArgument(args []string) error {
	if len(args) == 0 {
		return nil
	}
	if a.options.repo != "" {
		return clierr.Wrap(clierr.Usage, errors.New("supply the repository as an argument or --repo, not both"))
	}
	a.options.repo = args[0]
	return nil
}

// rejectRepoFlag fails when --repo is passed to a command that acts on no repository; suggest
// words the command the user probably meant for the owner that --repo names.
func (a *application) rejectRepoFlag(cmd *cobra.Command, suggest func(owner string) string) error {
	if a.options.repo == "" {
		return nil
	}
	text := "--repo is not used by " + strings.TrimPrefix(cmd.CommandPath(), cmd.Root().Name()+" ")
	if ref, err := settings.ParseRepository(a.options.repo, nil); err == nil && ref.Owner != "" {
		text += "; did you mean: " + suggest(ref.Owner)
	}
	return clierr.Wrap(clierr.Usage, errors.New(text))
}

func (a *application) repoCommand() *cobra.Command {
	group := &cobra.Command{
		Use:   "repo",
		Short: "Work with Gitea repositories",
		Long: `Work with Gitea repositories: list and view them, create, fork, clone and migrate them, keep
local branches and forks in sync, and change their settings.`,
	}
	group.AddCommand(a.repoListCommand(), a.repoViewCommand(), a.repositorySyncCommand())
	group.AddCommand(&cobra.Command{Use: "set-default [repository]", Short: "Save the selected repository in local Git configuration", Annotations: textOutput("set-default configures Git"), Args: usageArgs(cobra.MaximumNArgs(1)), RunE: func(cmd *cobra.Command, args []string) error {
		if err := a.repositoryArgument(args); err != nil {
			return err
		}
		target, err := a.resolve(cmd.Context(), true)
		if err != nil {
			return err
		}
		_, err = a.git(cmd.Context(), "config", "--local", "tea.repository", target.Host+"/"+target.Repo)
		return err
	}})
	a.addRepositoryMutations(group)
	return group
}

func (a *application) repoListCommand() *cobra.Command {
	var opts services.RepositoryListOptions
	list := &cobra.Command{
		Use:   "list [<owner>]",
		Short: "List repositories",
		Long: `List the repositories you can access, those of a user or organization, or the repositories you
starred or watch.`,
		Example: `# List the repositories you can access
$ tea repo list

# List the forks of an organization
$ tea repo list acme --type fork

# List your starred repositories as JSON
$ tea repo list --starred --json full_name,url`,
		Args: usageArgs(cobra.MaximumNArgs(1)),
		RunE: func(cmd *cobra.Command, args []string) error {
			if err := a.rejectRepoFlag(cmd, func(owner string) string { return "tea repo list " + owner }); err != nil {
				return err
			}
			if len(args) > 0 {
				if cmd.Flags().Changed("owner") {
					return clierr.Wrap(clierr.Usage, errors.New("supply the owner as an argument or --owner, not both"))
				}
				opts.Owner = args[0]
			}
			scopes := 0
			for _, selected := range []bool{opts.Owner != "", opts.Starred, opts.Watched} {
				if selected {
					scopes++
				}
			}
			if scopes > 1 {
				return clierr.Wrap(clierr.Usage, errors.New("an owner, --starred and --watched select different collections; pass one"))
			}
			target, err := a.resolve(cmd.Context(), false)
			if err != nil {
				return err
			}
			result, err := (services.Repositories{Client: target.client}).ListPage(cmd.Context(), opts)
			if err != nil {
				return err
			}
			collection := repositoryCollection(opts)
			spec := listSpec[services.Repository]{Columns: repositoryColumns, Row: repositoryRow, Context: collection, Empty: "no " + collection}
			return writeTable(a, cmd, result.Items, spec, listPage{Number: opts.Page, More: result.More, Total: result.Total, Counted: result.Counted})
		},
	}
	pageFlags(list, &opts.Limit, &opts.Page)
	list.Flags().StringVar(&opts.Owner, "owner", "", "List the repositories of this user or organization")
	_ = list.Flags().MarkHidden("owner")
	enumFlag(list, &opts.Kind, "type", "", "", "Only list repositories of this kind", "fork", "source", "mirror")
	list.Flags().BoolVar(&opts.Starred, "starred", false, "List your starred repositories")
	list.Flags().BoolVar(&opts.Watched, "watched", false, "List the repositories you watch")
	_ = list.RegisterFlagCompletionFunc("owner", a.completeOrgs())
	list.ValidArgsFunction = a.completeOrgs()
	return list
}

// repositoryCollection names the repositories that repo list selects, as in "forks owned by acme".
func repositoryCollection(opts services.RepositoryListOptions) string {
	kinds := map[string]string{"fork": "forks", "mirror": "mirrors", "source": "source repositories"}
	noun, ok := kinds[opts.Kind]
	if !ok {
		noun = "repositories"
	}
	switch {
	case opts.Owner != "":
		return noun + " owned by " + opts.Owner
	case opts.Starred:
		return "starred " + noun
	case opts.Watched:
		return "watched " + noun
	}
	return noun + " you can access"
}

// repositoryColumns head the rows of repositoryRow in repo list and search repo.
var repositoryColumns = []terminal.Column{{Header: "Name"}, {Header: "Description", Flex: true}, {Header: "Info"}, {Header: "Updated"}, {Header: "URL", PipedOnly: true}}

func repositoryRow(item services.Repository) []terminal.Cell {
	return []terminal.Cell{{Text: item.FullName, Link: item.URL}, {Text: item.Description}, {Text: strings.Join(repositoryInfo(item), ", ")}, {Time: terminal.ParseTime(item.UpdatedAt)}, {Text: item.URL}}
}

// repositoryInfo describes the visibility and the kind of a repository: public or private, then
// fork, mirror, template, archived or empty.
func repositoryInfo(item services.Repository) []string {
	info := []string{"public"}
	if item.Private {
		info[0] = "private"
	}
	for _, kind := range []struct {
		is   bool
		name string
	}{{item.Fork, "fork"}, {item.Mirror, "mirror"}, {item.Template, "template"}, {item.Archived, "archived"}, {item.Empty, "empty"}} {
		if kind.is {
			info = append(info, kind.name)
		}
	}
	return info
}

func (a *application) repoViewCommand() *cobra.Command {
	var web bool
	var branch string
	view := &cobra.Command{
		Use:   "view [<repository>]",
		Short: "View a repository",
		Long: `View a repository: its description, state, counts and clone URLs, followed by its README, which
is rendered on a terminal.`,
		Example: `# View the repository of the current clone
$ tea repo view

# View the README of another branch
$ tea repo view alice/project --branch develop

# Open the repository in the browser
$ tea repo view alice/project --web`,
		Annotations: map[string]string{"tea.arguments": repositoryArguments},
		Args:        usageArgs(cobra.MaximumNArgs(1)),
		RunE: func(cmd *cobra.Command, args []string) error {
			if err := a.repositoryArgument(args); err != nil {
				return err
			}
			target, err := a.resolve(cmd.Context(), true)
			if err != nil {
				return err
			}
			service := services.Repositories{Client: target.client}
			item, err := service.View(cmd.Context(), target.Repo)
			if err != nil {
				return err
			}
			if web {
				return a.openBrowser(cmd, item.URL)
			}
			readme := ""
			if a.options.json == "" && !item.Empty {
				if _, readme, err = service.Readme(cmd.Context(), target.Repo, branch); err != nil {
					return err
				}
			}
			return writeView(a, cmd, item, func(item services.Repository) terminal.View { return a.repositoryView(item, readme) })
		},
	}
	view.Flags().BoolVarP(&web, "web", "w", false, "Open the repository in the browser")
	view.Flags().StringVarP(&branch, "branch", "b", "", "Show the README of this branch (default: the default branch)")
	_ = view.RegisterFlagCompletionFunc("branch", a.completeBranches())
	view.ValidArgsFunction = a.completeRepos()
	return view
}

// repositoryView shows a repository with its README as the body.
func (a *application) repositoryView(item services.Repository, readme string) terminal.View {
	badges := []terminal.Cell{{Text: "public", Color: "green"}}
	if item.Private {
		badges[0] = terminal.Cell{Text: "private", Color: "yellow"}
	}
	for _, kind := range repositoryInfo(item)[1:] {
		badge := terminal.Cell{Text: kind, Muted: true}
		if kind == "archived" {
			badge = terminal.Cell{Text: "archived (read-only)", Color: "yellow"}
		}
		badges = append(badges, badge)
	}
	meta := []string{
		fmt.Sprintf("★ %d", item.Stars), countNoun(item.Forks, "fork"), countNoun(item.OpenIssues, "open issue"),
		countNoun(item.OpenPulls, "open pull request"),
	}
	if updated := terminal.ParseTime(item.UpdatedAt); !updated.IsZero() {
		meta = append(meta, "updated "+terminal.RelativeTime(a.deps.Now(), updated))
	}
	view := terminal.View{
		Title: item.FullName, Badges: badges, Meta: strings.Join(meta, " · "), Body: readme, Kind: "repository", URL: item.URL,
		Fields: []terminal.Field{
			{Label: "Description", Value: item.Description},
			{Label: "Forked from", Value: parentName(item)},
			{Label: "Mirror of", Value: mirrorSourceURL(item)},
			{Label: "Default branch", Value: item.DefaultBranch},
			{Label: "Website", Value: item.Website},
			{Label: "Topics", Value: strings.Join(item.Topics, ", ")},
			{Label: "Clone", Value: item.CloneURL},
			{Label: "SSH", Value: item.SSHURL},
		},
	}
	if a.deps.Streams.OutTTY && strings.TrimSpace(readme) == "" {
		view.Body = "_This repository has no README._"
		if item.Empty {
			view.Body = "_This repository is empty._"
		}
	}
	return view
}

func parentName(item services.Repository) string {
	if item.Parent == nil {
		return ""
	}
	return item.Parent.FullName
}

// countNoun counts n of a noun, as in "1 fork" or "3 forks".
func countNoun(n int, noun string) string {
	if n == 1 {
		return "1 " + noun
	}
	return fmt.Sprintf("%d %ss", n, noun)
}