package grid

import (
	"fmt"
	"strings"
	"time"

	"ticktock/internal/store"
)

// CellKind tags a LOGGED-column slot.
type CellKind int

const (
	CellEmpty CellKind = iota
	CellLabel
	CellCont
)

// Cell is one LOGGED-column slot.
type Cell struct {
	Kind    CellKind
	Key     string
	Project string
	Text    string
}

func hmm(d time.Duration) string {
	total := int(d.Minutes())
	return fmt.Sprintf("%d:%02d", total/60, total%60)
}

// labelFor renders a session's LOGGED label.
func labelFor(e store.Entry) string {
	tags := ""
	if len(e.Tags) > 0 {
		tags = " [" + strings.Join(e.Tags, ",") + "]"
	}
	return fmt.Sprintf("✓ %s%s (%s)", e.Description, tags, hmm(e.Duration))
}

// paintLogged builds the LOGGED column: one label per session on its first
// covered slot, continuation glyphs on later covered slots. Later-start wins a
// contested slot. Running entries run to the last row.
func paintLogged(g Grid, entries []store.Entry) []Cell {
	cells := make([]Cell, g.Rows)
	for _, e := range entries {
		startRow := g.RowOf(minuteOfDay(e.Start))
		var endRow int
		if e.Running() {
			endRow = g.Rows - 1
		} else {
			// end is exclusive; last covered slot holds end-1 minute
			endRow = g.RowOf(minuteOfDay(e.End) - 1)
		}
		if endRow < startRow {
			endRow = startRow
		}
		cells[startRow] = Cell{Kind: CellLabel, Key: e.Key, Project: e.Project, Text: labelFor(e)}
		for r := startRow + 1; r <= endRow && r < g.Rows; r++ {
			cells[r] = Cell{Kind: CellCont, Key: e.Key, Project: e.Project}
		}
	}
	return cells
}

// entryKeyAtRow returns the Key painted at row, if any.
func entryKeyAtRow(cells []Cell, row int) (string, bool) {
	if row < 0 || row >= len(cells) {
		return "", false
	}
	if cells[row].Kind == CellEmpty || cells[row].Key == "" {
		return "", false
	}
	return cells[row].Key, true
}