// Package help renders help and help-brief output for the hf CLI.
package help

import (
	"fmt"
	"strings"
)

// Command describes a CLI command or group.
type Command struct {
	Name        string
	Description string
	Permitted   bool // whether the current user can execute this
	SubCommands []Command
}

// Group describes a top-level command group.
type Group struct {
	Name        string
	Description string
	Permitted   bool
	SubCommands []Command
}

// RenderTopHelp renders `hf --help` output showing all groups.
func RenderTopHelp(version string, groups []Group) string {
	var b strings.Builder
	b.WriteString("hf - HarborForge CLI")
	if version != "" {
		b.WriteString(" (" + version + ")")
	}
	b.WriteString("\n\nUsage: hf <command> [flags]\n\n")
	b.WriteString("Commands:\n")
	maxLen := 0
	for _, g := range groups {
		if len(g.Name) > maxLen {
			maxLen = len(g.Name)
		}
	}
	for _, g := range groups {
		b.WriteString(fmt.Sprintf("  %-*s  %s\n", maxLen, g.Name, g.Description))
	}
	b.WriteString("\nGlobal flags:\n")
	b.WriteString("  --help        Show help\n")
	b.WriteString("  --help-brief  Show only permitted commands\n")
	b.WriteString("  --json        Output in JSON format\n")
	return b.String()
}

// RenderTopHelpBrief renders `hf --help-brief` showing only permitted groups.
func RenderTopHelpBrief(version string, groups []Group) string {
	var b strings.Builder
	b.WriteString("hf - HarborForge CLI")
	if version != "" {
		b.WriteString(" (" + version + ")")
	}
	b.WriteString("\n\nPermitted commands:\n")
	maxLen := 0
	for _, g := range groups {
		if g.Permitted && len(g.Name) > maxLen {
			maxLen = len(g.Name)
		}
	}
	for _, g := range groups {
		if g.Permitted {
			b.WriteString(fmt.Sprintf("  %-*s  %s\n", maxLen, g.Name, g.Description))
		}
	}
	return b.String()
}

// RenderGroupHelp renders `hf <group> --help` showing all subcommands.
func RenderGroupHelp(groupName string, cmds []Command) string {
	var b strings.Builder
	b.WriteString(fmt.Sprintf("hf %s - subcommands:\n\n", groupName))
	maxLen := 0
	for _, c := range cmds {
		if len(c.Name) > maxLen {
			maxLen = len(c.Name)
		}
	}
	for _, c := range cmds {
		desc := c.Description
		if !c.Permitted {
			desc = "(not permitted)"
		}
		b.WriteString(fmt.Sprintf("  %-*s  %s\n", maxLen, c.Name, desc))
	}
	return b.String()
}

// RenderGroupHelpBrief renders `hf <group> --help-brief` showing only permitted subcommands.
func RenderGroupHelpBrief(groupName string, cmds []Command) string {
	var b strings.Builder
	b.WriteString(fmt.Sprintf("hf %s - permitted subcommands:\n\n", groupName))
	maxLen := 0
	for _, c := range cmds {
		if c.Permitted && len(c.Name) > maxLen {
			maxLen = len(c.Name)
		}
	}
	for _, c := range cmds {
		if c.Permitted {
			b.WriteString(fmt.Sprintf("  %-*s  %s\n", maxLen, c.Name, c.Description))
		}
	}
	return b.String()
}

// RenderNotPermitted renders the short message for an unpermitted leaf command.
func RenderNotPermitted(group, cmd string) string {
	return fmt.Sprintf("hf %s %s: not permitted", group, cmd)
}