package gui

import (
	"fmt"
	"regexp"
	"strconv"
	"strings"

	"github.com/fatih/color"
	"github.com/isacikgoz/gitbatch/internal/command"
	"github.com/isacikgoz/gitbatch/internal/git"
	"github.com/isacikgoz/gitbatch/internal/job"
)

var (
	blue    = color.New(color.FgBlue)
	green   = color.New(color.FgGreen)
	red     = color.New(color.FgRed)
	cyan    = color.New(color.FgCyan)
	yellow  = color.New(color.FgYellow)
	magenta = color.New(color.FgMagenta)

	keySymbol = " " + yellow.Sprint("🔑") + ws
	sep       = " " + yellow.Sprint("|") + ws

	pushable = "↖"
	pullable = "↘"
)

const (
	maxBranchLength     = 40
	maxRepositoryLength = 80
	hashLength          = 7

	ws            = " "
	queuedSymbol  = "•"
	workingSymbol = "•"
	successSymbol = "✔"
	failSymbol    = "✗"

	fetchSymbol         = "↓"
	pullSymbol          = "↓↳"
	mergeSymbol         = "↳"
	checkoutSymbol      = "↱"
	modeSeperator       = ""
	keyBindingSeperator = "░"

	selectionIndicator = "→" + ws
	tab                = ws
)

// RepositoryDecorationRules is a rule set for creating repository labels
type RepositoryDecorationRules struct {
	MaxName      int
	MaxPushables int
	MaxPullables int
	MaxBranch    int
}

// repository render rules
func (gui *Gui) renderRules() *RepositoryDecorationRules {
	rules := &RepositoryDecorationRules{
		MaxBranch: 15,
		MaxName:   30,
	}

	for _, r := range gui.State.Repositories {
		if len(r.State.Branch.Pullables) > rules.MaxPullables {
			rules.MaxPullables = len(r.State.Branch.Pullables)
		}
		if len(r.State.Branch.Pushables) > rules.MaxPushables {
			rules.MaxPushables = len(r.State.Branch.Pushables)
		}
		if len(r.State.Branch.Name) > maxBranchLength {
			rules.MaxBranch = maxBranchLength
		}
		if len(r.Name) > maxRepositoryLength {
			rules.MaxName = maxRepositoryLength
		}
	}

	rules.MaxBranch = rules.MaxBranch + len(cyan.Sprint("")) + 2
	return rules
}

// this function handles the render and representation of the repository
// TODO: cleanup is required, right now it looks too complicated
func (gui *Gui) repositoryLabel(r *git.Repository) string {
	renderRules := gui.renderRules()

	gui.renderTableHeader(renderRules)

	var line string

	line = line + renderRevCount(r, renderRules) + sep
	line = line + renderBranchName(r, renderRules) + sep
	line = line + gui.renderRepoName(r, renderRules) + sep
	line = line + gui.renderStatus(r)

	return line
}

// render repo name, print green if cursor is on the repository
func (gui *Gui) renderRepoName(r *git.Repository, rule *RepositoryDecorationRules) string {
	var repoName string
	sr := gui.getSelectedRepository()
	if sr == r {
		n, in := align(r.Name, rule.MaxName-2, true)
		in = in + strings.Repeat(" ", n)
		return selectionIndicator + green.Sprint(in)
	}

	n, in := align(r.Name, rule.MaxName, true)
	in = in + strings.Repeat(" ", n)
	repoName = in

	return repoName
}

// render branch, add x if it is dirty
func renderBranchName(r *git.Repository, rule *RepositoryDecorationRules) string {
	b := r.State.Branch
	branch := b.Name
	if !b.Clean {
		n, in := align(branch, rule.MaxBranch-2, true)
		return cyan.Sprint(in) + " " + yellow.Sprint("✗") + strings.Repeat(" ", n)
	}
	n, in := align(branch, rule.MaxBranch, true)
	return cyan.Sprint(in) + strings.Repeat(" ", n)
}

// render ahead and behind info
func renderRevCount(r *git.Repository, rule *RepositoryDecorationRules) string {
	var revCount string
	b := r.State.Branch
	if b.Pushables != "?" {
		n1, part1 := align(b.Pushables, rule.MaxPushables, false)
		n2, part2 := align(b.Pullables, rule.MaxPullables, false)
		revCount = blue.Sprint(pushable) + ws + strings.Repeat(" ", n1) + part1 +
			ws + blue.Sprint(pullable) + ws + strings.Repeat(" ", n2) + part2
	} else {
		n1, part1 := align(b.Pushables, rule.MaxPushables, false)
		n2, part2 := align(b.Pullables, rule.MaxPullables, false)
		revCount = blue.Sprint(pushable) + ws + strings.Repeat(" ", n1) + yellow.Sprint(part1) +
			ws + blue.Sprint(pullable) + ws + strings.Repeat(" ", n2) + yellow.Sprint(part2)
	}
	return revCount
}

// render working status of the repository
func (gui *Gui) renderStatus(r *git.Repository) string {
	var status string
	if r.WorkStatus() == git.Queued {
		if inQueue, j := gui.State.Queue.IsInTheQueue(r); inQueue {
			status = printQueued(r, j)
		}
	} else if r.WorkStatus() == git.Working {
		status = green.Sprint(workingSymbol) + ws + r.State.Message
	} else if r.WorkStatus() == git.Success {
		status = green.Sprint(successSymbol) + ws + r.State.Message
	} else if r.WorkStatus() == git.Paused {
		status = yellow.Sprint("! authentication required (u)")
	} else if r.WorkStatus() == git.Fail {
		status = red.Sprint(failSymbol) + ws + red.Sprint(r.State.Message)
	}
	return status
}

// render header of the table layout
func (gui *Gui) renderTableHeader(rule *RepositoryDecorationRules) {
	v, err := gui.g.View(mainViewFrameFeature.Name)
	if err != nil {
		return
	}
	v.Clear()
	var header string
	revlen := 2 + rule.MaxPullables + 2 + rule.MaxPushables + 1
	n, in := align("revs", revlen, true)
	header = ws + magenta.Sprint(in) + strings.Repeat(" ", n) + sep
	n, in = align("branch", rule.MaxBranch, true)
	header = header + magenta.Sprint(in) + strings.Repeat(" ", n) + sep
	n, in = align("name", rule.MaxName, true)
	header = header + magenta.Sprint(in) + strings.Repeat(" ", n) + sep
	fmt.Fprintln(v, header)
}

// print queued item with the mode color
func printQueued(r *git.Repository, j *job.Job) string {
	var info string
	switch jt := j.JobType; jt {
	case job.FetchJob:
		info = blue.Sprint(queuedSymbol) + ws + "(" + blue.Sprint("fetch") + ws + r.State.Remote.Name + ")"
	case job.PullJob:
		info = magenta.Sprint(queuedSymbol) + ws + "(" + magenta.Sprint("pull") + ws + r.State.Remote.Name + ")"
	case job.MergeJob:
		info = cyan.Sprint(queuedSymbol) + ws + "(" + cyan.Sprint("merge") + ws + r.State.Branch.Upstream.Name + ")"
	case job.CheckoutJob:
		refName := j.Options.(*command.CheckoutOptions).TargetRef
		info = green.Sprint(queuedSymbol) + ws + "(" + cyan.Sprint("switch branch to") + ws + refName + ")"
	default:
		info = green.Sprint(queuedSymbol)
	}
	return info
}

// render commit label according to its status(local/even/remote)
func commitLabel(c *git.Commit, sel bool) string {
	re := regexp.MustCompile(`\r?\n`)
	msg := re.ReplaceAllString(c.Message, " ")
	if sel {
		msg = green.Sprint(msg)
	}
	var body string
	switch c.CommitType {
	case git.EvenCommit:
		body = cyan.Sprint(c.Hash[:hashLength]) + " " + msg
	case git.LocalCommit:
		body = blue.Sprint(c.Hash[:hashLength]) + " " + msg
	case git.RemoteCommit:
		if len(c.Hash) > hashLength {
			body = yellow.Sprint(c.Hash[:hashLength]) + " " + msg
		} else {
			body = yellow.Sprint(c.Hash[:len(c.Hash)]) + " " + msg
		}
	default:
		body = c.Hash[:hashLength] + " " + msg
	}
	return body
}

// colorize the plain diff text collected from system output
// the style is near to original diff command
func colorizeDiff(original string) (colorized []string) {
	colorized = strings.Split(original, "\n")
	re := regexp.MustCompile(`@@ .+ @@`)
	for i, line := range colorized {
		if len(line) > 0 {
			switch rn := line[0]; rn {
			case '-':
				colorized[i] = red.Sprint(line)
				continue
			case '+':
				colorized[i] = green.Sprint(line)
				continue
			default:
			}

			if re.MatchString(line) {
				s := re.FindString(line)
				colorized[i] = cyan.Sprint(s) + line[len(s):]
			}
			continue

		} else {
			continue
		}
	}
	return colorized
}

// the remote link can be too verbose sometimes, so it is good to trim it
func trimRemoteURL(url string) (urltype string, shorturl string) {
	// lets trim the unnecessary .git extension of the url
	regit := regexp.MustCompile(`.git`)
	if regit.MatchString(url[len(url)-4:]) {
		url = url[:len(url)-4]
	}

	// find out the protocol
	ressh := regexp.MustCompile(`git@`)
	rehttp := regexp.MustCompile(`http://`)
	rehttps := regexp.MustCompile(`https://`)

	// separate the protocol and remote link
	if ressh.MatchString(url) {
		shorturl = ressh.Split(url, 5)[1]
		urltype = "ssh"
	} else if rehttp.MatchString(url) {
		shorturl = rehttp.Split(url, 5)[1]
		urltype = "http"
	} else if rehttps.MatchString(url) {
		shorturl = rehttps.Split(url, 5)[1]
		urltype = "https"
	}
	return urltype, shorturl
}

// DiffStatDecorationRules is a rule set for creating diffstat text
type DiffStatDecorationRules struct {
	MaxNameLength        int
	MaxChangeCountLength int
	MaxChangesLength     int
}

// DiffStatItem is a line of a diff stat
type DiffStatItem struct {
	FileName    string
	ChangeCount string
	Changes     string
}

// get output of "git show <commit> --shortstat" and convert it to DiffStatItem
// slice and generate rules
func genDiffStat(in string) (*DiffStatDecorationRules, []*DiffStatItem) {
	rules := &DiffStatDecorationRules{}
	stats := make([]*DiffStatItem, 0)

	re := regexp.MustCompile(`\s+\|\s+`)
	r1 := regexp.MustCompile(`\d+\s+`)

	for _, line := range strings.Split(in, "\n") {
		s := re.Split(line, 2)
		ds := &DiffStatItem{}
		ds.FileName = s[0]

		if rules.MaxNameLength < len(ds.FileName) {
			rules.MaxNameLength = len(ds.FileName)
		}

		if len(s) > 1 && r1.MatchString(s[1]) {
			cc := r1.FindString(s[1])
			ds.ChangeCount = strings.TrimSpace(cc)
			if rules.MaxChangeCountLength < len(ds.ChangeCount) {
				rules.MaxChangeCountLength = len(ds.ChangeCount)
			}
			d := r1.Split(s[1], 2)

			ds.Changes = d[1]
			if rules.MaxChangesLength < len(ds.Changes) {
				rules.MaxChangesLength = len(ds.Changes)
			}
		}
		stats = append(stats, ds)
	}
	return rules, stats
}

// colorize diff stat
func decorateDiffStat(in string, sum bool) string {
	var d string

	s := strings.Split(in, "\n")
	if sum {
		d = strconv.Itoa(len(s)-1) + " file(s) changed." + "\n\n"
	}
	rule, stats := genDiffStat(in)
	for _, stat := range stats {
		if len(stat.FileName) <= 0 {
			continue
		}
		n1, part1 := align(stat.FileName, rule.MaxNameLength, true)
		n2, part2 := align(stat.ChangeCount, rule.MaxChangeCountLength, false)
		d = d + cyan.Sprint(part1) + strings.Repeat(" ", n1) + yellow.Sprint(" | ") + strings.Repeat(" ", n2) + part2 + " "
		for _, r := range stat.Changes {
			switch r {
			case '+':
				d = d + green.Sprint(string(r))
			case '-':
				d = d + red.Sprint(string(r))
			default:
				d = d + string(r)
			}
		}
		d = d + "\n"
	}
	return d
}

// align text with whitespaces
func align(in string, max int, trim bool) (int, string) {
	realmax := 50
	il := len(in)
	if max > realmax {
		max = 50
	}
	if trim && il > max {
		return 0, in[:max-2] + ".."
	}
	if il < max {
		return max - il, in
		//true
		//in = in + strings.Repeat(" ", max-il)
		//false
		//return max-il, in
		//in = strings.Repeat(" ", max-il) + in
	}
	return 0, in
}

// colorize commit info
func decorateCommit(in string) string {
	var d string
	lines := strings.Split(in, "\n")
	d = d + strings.Replace(lines[0], "Hash:", cyan.Sprint("Hash:"), 1) + "\n"
	d = d + strings.Replace(lines[1], "Author:", cyan.Sprint("Author:"), 1) + "\n"
	d = d + strings.Replace(lines[2], "Date:", cyan.Sprint("Date:"), 1) + "\n"
	for _, l := range lines[3:] {
		d = d + l + "\n"
	}
	return d
}