package commandkit

import (
	"sort"

	internalcobra "gitea.maximumdirect.net/eric/CommandKit/internal/cobra"
	commandmeta "gitea.maximumdirect.net/eric/CommandKit/internal/commandmeta"
	"gitea.maximumdirect.net/eric/CommandKit/internal/commandpath"
)

func (a *App) parse(args []string, options commandmeta.ParseOptions) commandmeta.Result {
	if a == nil {
		return commandmeta.Result{Failure: &commandmeta.Failure{Message: "cannot parse commands on a nil app"}}
	}
	return internalcobra.Parse(a.routeSnapshot().metadata, args, options)
}

func (a *App) routeSnapshot() *routingSnapshot {
	if a == nil {
		return nil
	}
	if a.snapshot == nil {
		a.snapshot = a.buildRoutingSnapshot()
	}
	return a.snapshot
}

func (a *App) buildRoutingSnapshot() *routingSnapshot {
	root := &commandmeta.Command{Name: a.identity.Name, CoreFlags: commandmeta.ReportingFlags()}
	snapshot := &routingSnapshot{
		metadata:       root,
		runners:        make(map[commandmeta.Key]commandPayload),
		aliases:        a.aliases,
		canonical:      buildCanonicalTree(a.commands),
		flagAliases:    a.flagAliases,
		discoveryFlags: a.discoveryFlags,
	}
	for _, rule := range a.routingRules {
		if rule.record.kind != commandAliasRule {
			continue
		}
		snapshot.commandAliases = append(snapshot.commandAliases, commandmeta.CommandAlias{
			Source: []string(rule.record.sourcePath.Clone()),
			Target: []string(snapshot.aliases.Resolve(rule.record.targetPath)),
		})
	}
	sort.Slice(snapshot.commandAliases, func(i, j int) bool {
		return commandpath.FromTokens(snapshot.commandAliases[i].Source).Key() < commandpath.FromTokens(snapshot.commandAliases[j].Source).Key()
	})
	names := make([]string, 0, len(a.commands))
	for name := range a.commands {
		names = append(names, name)
	}
	sort.Strings(names)
	var key commandmeta.Key
	for _, name := range names {
		root.Children = append(root.Children, bridgeCommand(a.commands[name].command, snapshot, &key))
	}
	return snapshot
}

func bridgeCommand(command Command, snapshot *routingSnapshot, next *commandmeta.Key) *commandmeta.Command {
	record := command.record
	*next = *next + 1
	declaration := &commandmeta.Command{
		Key:         *next,
		Name:        record.name,
		Summary:     record.summary,
		Description: record.description,
		CoreFlags:   commandmeta.ReportingFlags(),
	}
	if record.payload != nil {
		snapshot.runners[declaration.Key] = record.payload
		declaration.Runnable = record.payload.hasRun()
		declaration.Flags = record.payload.bridgeFlags()
		declaration.Arguments = record.payload.bridgeArguments()
	}
	children := append([]Command(nil), record.children...)
	sort.Slice(children, func(i, j int) bool { return children[i].record.name < children[j].record.name })
	for _, child := range children {
		if child.record == nil || child.record.absent {
			continue
		}
		declaration.Children = append(declaration.Children, bridgeCommand(child, snapshot, next))
	}
	return declaration
}