package mergeconflicts

import (
	"bytes"

	"github.com/fatih/color"
	"github.com/jesseduffield/lazygit/pkg/theme"
	"github.com/jesseduffield/lazygit/pkg/utils"
)

func ColoredConflictFile(content string, state *State, hasFocus bool) string {
	if len(state.conflicts) == 0 {
		return content
	}
	conflict, remainingConflicts := shiftConflict(state.conflicts)
	var outputBuffer bytes.Buffer
	for i, line := range utils.SplitLines(content) {
		colourAttr := theme.DefaultTextColor
		if i == conflict.start || i == conflict.middle || i == conflict.end {
			colourAttr = color.FgRed
		}
		colour := color.New(colourAttr)
		if hasFocus && state.conflictIndex < len(state.conflicts) && *state.conflicts[state.conflictIndex] == *conflict && shouldHighlightLine(i, conflict, state.conflictTop) {
			colour.Add(color.Bold)
			colour.Add(theme.SelectedRangeBgColor)
		}
		if i == conflict.end && len(remainingConflicts) > 0 {
			conflict, remainingConflicts = shiftConflict(remainingConflicts)
		}
		outputBuffer.WriteString(utils.ColoredStringDirect(line, colour) + "\n")
	}
	return outputBuffer.String()
}

func shiftConflict(conflicts []*mergeConflict) (*mergeConflict, []*mergeConflict) {
	return conflicts[0], conflicts[1:]
}

func shouldHighlightLine(index int, conflict *mergeConflict, top bool) bool {
	return (index >= conflict.start && index <= conflict.middle && top) || (index >= conflict.middle && index <= conflict.end && !top)
}