package formatter

import (
	"fmt"
	"io"
	"strings"
	"unicode/utf8"

	"royalroadupdates/internal/royalroad"
)

// PrintTable writes a plain-text aligned table of stories to w.
func PrintTable(w io.Writer, stories []royalroad.Story) {
	if len(stories) == 0 {
		return
	}

	nameHeader := "Story Name"
	updateHeader := "Last Update"

	// 1. Measure natural widths in runes
	maxNameLen := utf8.RuneCountInString(nameHeader)
	maxUpdateLen := utf8.RuneCountInString(updateHeader)

	for _, s := range stories {
		if l := utf8.RuneCountInString(s.Name); l > maxNameLen {
			maxNameLen = l
		}
		if l := utf8.RuneCountInString(Relative(s.DateModified)); l > maxUpdateLen {
			maxUpdateLen = l
		}
	}

	// 2. Determine final name column width based on terminal availability
	nameWidth := maxNameLen
	const minNameWidth = 30
	const gutter = 2

	termWidth, err := getTerminalWidth()
	if err == nil {
		// We have a terminal. check if it's wide enough to support a cap above the min.
		if termWidth >= minNameWidth+gutter+maxUpdateLen {
			availableForName := termWidth - gutter - maxUpdateLen
			if nameWidth > availableForName {
				nameWidth = availableForName
			}
		}
	}

	// 3. Render Table
	fmt.Fprintf(w, "%-*s  %s\n", nameWidth, nameHeader, updateHeader)
	fmt.Fprintf(w, "%s  %s\n", strings.Repeat("-", nameWidth), strings.Repeat("-", maxUpdateLen))

	for _, s := range stories {
		displayName := s.Name
		runeName := []rune(displayName)
		if len(runeName) > nameWidth {
			// Truncate to (nameWidth - 3) and add ellipsis
			displayName = string(runeName[:nameWidth-3]) + "..."
		}
		fmt.Fprintf(w, "%-*s  %s\n", nameWidth, displayName, Relative(s.DateModified))
	}
}