package main

import (
	"bufio"
	"fmt"
	"io"
	"sort"

	"git.xdrm.io/go/cliverage/coverage"
)

func bold(str string) string {
	return fmt.Sprintf("\x1b[1m%s\x1b[0m", str)
}

func success(str string) string {
	return fmt.Sprintf("\x1b[38;2;26;221;120m%s\x1b[0m", str)
}

func warning(str string) string {
	return fmt.Sprintf("\x1b[38;2;221;26;120m%s\x1b[0m", str)
}

func printCoverage(r io.Reader, w io.Writer, chunks []coverage.Coverage) error {
	reader := bufio.NewReader(r)
	linen := uint64(0)
	eof := false

	coverPrefix := "\x1b[38;2;26;221;120m"
	coverSuffix := "\x1b[0m"
	// coverPrefix := "<<<"
	// coverSuffix := ">>>"

	for true {
		linen++
		if eof {
			break
		}

		line, err := reader.ReadString('\n')
		if err == io.EOF {
			if len(line) < 1 {
				break
			} else {
				eof = true
			}
		} else if err != nil {
			return err
		}

		// check if we got a chunk start
		concerned := make([]coverage.Coverage, 0)
		for _, c := range chunks {
			if c.StartLine == linen || c.EndLine == linen {
				concerned = append(concerned, c)
			}
		}
		// sort by max column before
		sort.Slice(concerned, sortChunksByColumn(concerned, linen))

		// if no coverage, write directly
		if len(concerned) < 1 {
			_, err := w.Write([]byte(fmt.Sprintf("%d\t| %s", linen, line)))
			if err != nil {
				return err
			}
			continue
		}

		// position each column with its prefix/suffix
		for _, chunk := range concerned {
			isStart := chunk.StartLine == linen
			isEnd := chunk.EndLine == linen

			if isStart && isEnd {
				firstColumn := chunk.StartColumn
				prefix := coverPrefix
				lastColumn := chunk.EndColumn
				suffix := coverSuffix
				if chunk.EndColumn > chunk.StartColumn {
					firstColumn = chunk.EndColumn
					prefix = coverSuffix
					lastColumn = chunk.StartColumn
					suffix = coverPrefix
				}

				line = line[0:firstColumn-1] + prefix + line[firstColumn-1:]
				if firstColumn != lastColumn {
					line = line[0:lastColumn-1] + suffix + line[lastColumn-1:]
				}

				continue
			}

			if isEnd {
				line = line[0:chunk.EndColumn-1] + coverSuffix + line[chunk.EndColumn-1:]
			} else if isStart {
				line = line[0:chunk.StartColumn-1] + coverPrefix + line[chunk.StartColumn-1:]
				continue
			}
		}

		_, err = w.Write([]byte(fmt.Sprintf("%d\t| %s", linen, line)))
		if err != nil {
			return err
		}

	}
	return nil

}

func sortChunksByColumn(chunks []coverage.Coverage, lineNumber uint64) func(i, j int) bool {
	return func(i, j int) bool {
		// if start is concerned
		iConcernedColumn := chunks[i].StartColumn
		if chunks[i].EndLine == lineNumber {
			iConcernedColumn = chunks[i].EndColumn
			if chunks[i].StartLine == lineNumber && chunks[i].StartColumn > iConcernedColumn {
				iConcernedColumn = chunks[i].StartColumn
			}
		}

		jConcernedColumn := chunks[j].StartColumn
		if chunks[j].EndLine == lineNumber {
			jConcernedColumn = chunks[j].EndColumn
			if chunks[j].StartLine == lineNumber && chunks[j].StartColumn > jConcernedColumn {
				jConcernedColumn = chunks[j].StartColumn
			}
		}

		if iConcernedColumn == jConcernedColumn {
			// return the closing chunk before
			if chunks[i].StartLine == lineNumber && chunks[j].EndLine == lineNumber {
				return true
			}
			if chunks[i].EndLine == lineNumber && chunks[j].StartLine == lineNumber {
				return false
			}
		}

		return iConcernedColumn >= jConcernedColumn
	}
}