package views

import (
	"strconv"

	"hearthforge/internal/config"
	"hearthforge/internal/db"
	"hearthforge/internal/gitcmd"
	"hearthforge/internal/highlight"
	"hearthforge/internal/util"

	g "maragu.dev/gomponents"
	. "maragu.dev/gomponents/html"
)

// Ref name and message caps.
const (
	maxBranchNameLength = 255
	maxTagNameLength    = 255
	maxTagMessageLength = 500
)

// sigBadge renders the signature badge, or nothing for an unsigned commit.
func sigBadge(status gitcmd.SigStatus) g.Node {
	switch status {
	case gitcmd.SigGood:
		return Span(Class("sig-badge verified"), g.Text("verified"))
	case gitcmd.SigBad:
		return Span(Class("sig-badge unverified"), g.Text("unverified"))
	}
	return nil
}

// CommitLog renders the commit history with cursor pagination.
// olderURL and newerURL are empty when that direction has no page.
func CommitLog(cfg *config.Config, user *db.SessionUser, repo *db.Repo, logRef string,
	commits []gitcmd.Commit, branches, tags []string, olderURL, newerURL string,
) g.Node {
	return Layout(Page{Title: "Commits — " + repo.Name, User: user, Cfg: cfg},
		Div(Class("container"),
			RepoHeader(repo),
			RepoNav(repo, "commits", user),
			Div(Class("commits-header"),
				H2(Class("section-title"), g.Text("Commits")),
				BranchSelector(repo.Name, branches, tags, logRef, "commits", ""),
			),
			g.If(len(commits) == 0, P(Class("text-muted"), g.Text("No commits yet."))),
			g.If(len(commits) > 0, g.Group{
				P(Class("commit-verify-hint"),
					g.Text("Note: To verify signed commits locally, download the "),
					A(Href("/allowed_signers"), g.Text("allowed signers file")),
					g.Text(" and run: "),
					Code(Class("mono"),
						g.Text("git -c gpg.format=ssh -c gpg.ssh.allowedSignersFile=allowed_signers verify-commit <hash>")),
				),
				Ul(Class("commit-list commit-log"),
					g.Map(commits, func(c gitcmd.Commit) g.Node {
						short := c.Hash
						if len(short) > 7 {
							short = short[:7]
						}
						return Li(Class("commit-item"),
							A(Href("/"+repo.Name+"/commit/"+c.Hash), Class("commit-subject"),
								g.Text(c.Subject)),
							Div(Class("commit-meta"),
								Span(Class("commit-author"), g.Text(c.Author)),
								Span(Class("commit-meta-right"),
									sigBadge(c.SigStatus),
									A(Href("/"+repo.Name+"/commit/"+c.Hash), Class("commit-hash mono"),
										g.Text(short)),
									Time(Class("commit-date"), DateTime(c.Date),
										g.Text(util.FormatDateTime(c.Date))),
								),
							),
						)
					}),
				),
			}),
			g.If(newerURL != "" || olderURL != "",
				Nav(Class("commit-cursor-nav"), Aria("label", "Commit history navigation"),
					Div(Class("commit-cursor-prev"),
						g.If(newerURL != "",
							A(Href(newerURL), Class("pagination-btn"), g.Text("← Newer"))),
					),
					Div(Class("commit-cursor-next"),
						g.If(olderURL != "",
							A(Href(olderURL), Class("pagination-btn"), g.Text("Older →"))),
					),
				)),
		),
	)
}

// CommitDetail renders one commit with its diff. tooLarge is the raw diff size
// when the diff was skipped, and 0 when the diff was rendered.
func CommitDetail(cfg *config.Config, user *db.SessionUser, repo *db.Repo, sha string,
	meta *gitcmd.CommitMeta, files []highlight.RenderedDiffFile, tooLarge int,
) g.Node {
	short := sha
	if len(short) > 7 {
		short = short[:7]
	}
	subject := meta.Subject
	subjectClass := "commit-card-subject"
	if subject == "" {
		subject = "No commit message"
		subjectClass = "commit-card-subject commit-card-subject-empty"
	}
	differentCommitter := meta.Committer != meta.Author || meta.CommitterEmail != meta.Email

	return Layout(Page{Title: short + " — " + repo.Name, User: user, Cfg: cfg},
		Div(Class("container"),
			RepoHeader(repo),
			RepoNav(repo, "commits", user),
			Div(Class("commit-page-top"),
				A(Href("/"+repo.Name+"/commits/"+EscapePath(repo.DefaultBranch)), Class("btn btn-sm"),
					g.Text("← Back to log")),
				A(Href("/"+repo.Name+"/tree/"+sha), Class("btn btn-secondary btn-sm"),
					Title("Browse tree at "+short), g.Text("@ "+short)),
			),
			Div(Class("commit-card"),
				H2(Class(subjectClass), g.Text(subject)),
				g.If(meta.Body != "", Pre(Class("commit-card-body"), g.Text(meta.Body))),
				Div(Class("commit-card-meta"),
					metaRow("Author", Span(Class("commit-meta-value"),
						g.Text(meta.Author+" <"+meta.Email+">"))),
					metaRow("Date", Time(Class("commit-meta-value"), DateTime(meta.Date),
						g.Text(util.FormatDateTime(meta.Date)))),
					g.If(differentCommitter, g.Group{
						metaRow("Committer", Span(Class("commit-meta-value"),
							g.Text(meta.Committer+" <"+meta.CommitterEmail+">"))),
						metaRow("Commit date", Time(Class("commit-meta-value"),
							DateTime(meta.CommitterDate), g.Text(util.FormatDateTime(meta.CommitterDate)))),
					}),
					metaRow("Commit", Code(Class("commit-meta-value commit-sha-full mono"),
						g.Text(meta.Hash))),
					g.If(len(meta.Parents) > 0, metaRow(parentLabel(len(meta.Parents)),
						Span(Class("commit-meta-value"),
							g.Map(meta.Parents, func(p string) g.Node {
								ps := p
								if len(ps) > 7 {
									ps = ps[:7]
								}
								return A(Href("/"+repo.Name+"/commit/"+p), Class("commit-hash mono"),
									g.Text(ps))
							})))),
					g.If(meta.SigStatus != gitcmd.SigNone, metaRow("Signature",
						Span(Class("commit-meta-value"), sigBadge(meta.SigStatus)))),
				),
			),
			g.If(tooLarge > 0, Div(Class("file-download-notice"),
				P(g.Text("Diff is too large to render inline ("+
					formatMB(tooLarge)+" MB). Browse individual files at the tree below.")),
			)),
			g.If(tooLarge == 0, DiffView(files, repo, sha)),
		),
	)
}

func metaRow(label string, value g.Node) g.Node {
	return Div(Class("commit-card-meta-row"),
		Span(Class("commit-meta-label"), g.Text(label)),
		value,
	)
}

func parentLabel(n int) string {
	if n > 1 {
		return "Parents"
	}
	return "Parent"
}

// formatMB renders a byte count as megabytes with one decimal.
func formatMB(bytes int) string {
	return strconv.FormatFloat(float64(bytes)/1024/1024, 'f', 1, 64)
}

// BranchList renders the branch overview with admin actions.
func BranchList(cfg *config.Config, user *db.SessionUser, repo *db.Repo, branches []gitcmd.BranchInfo,
	page PageInfo, success, errMsg string,
) g.Node {
	isAdmin := user != nil && user.IsAdmin
	return Layout(Page{Title: "Branches — " + repo.Name, User: user, Cfg: cfg},
		Div(Class("container"),
			RepoHeader(repo),
			RepoNav(repo, "branches", user),
			g.If(success != "", P(Class("form-success"), g.Text(success))),
			g.If(errMsg != "", P(Class("form-error"), g.Text(errMsg))),
			Div(Class("list-header"),
				H2(Class("list-heading"), g.Text("Branches")),
				g.If(isAdmin, Details(Class("confirm-details"),
					Summary(Class("btn btn-primary btn-sm"), g.Text("New branch")),
					Div(Class("confirm-popup confirm-popup-form"),
						Form(Method("POST"), Action("/"+repo.Name+"/branches/create"), Class("popup-form"),
							Div(Class("form-group"),
								Label(For("new-branch-name"), g.Text("Branch name")),
								Input(ID("new-branch-name"), Name("name"), Type("text"), Required(),
									Placeholder("feature/my-branch"),
									MaxLength(strconv.Itoa(maxBranchNameLength))),
							),
							Div(Class("form-group"),
								Label(For("new-branch-source"), g.Text("From")),
								Input(ID("new-branch-source"), Name("source_ref"), Type("text"), Required(),
									Value(repo.DefaultBranch), Placeholder("branch, tag, or commit"),
									MaxLength(strconv.Itoa(maxBranchNameLength))),
							),
							Button(Type("submit"), Class("btn btn-primary btn-sm"), g.Text("Create branch")),
						),
					),
				)),
			),
			g.If(len(branches) == 0, Div(Class("empty-state"), P(g.Text("No branches yet.")))),
			g.If(len(branches) > 0, Ul(Class("ref-list"),
				g.Map(branches, func(b gitcmd.BranchInfo) g.Node {
					return Li(Class("ref-item"),
						Div(Class("ref-name-row"),
							A(Href("/"+repo.Name+"/tree/"+EscapePath(b.Name)), Class("ref-name"), g.Text(b.Name)),
							g.If(b.Name == repo.DefaultBranch, Span(Class("badge"), g.Text("default"))),
							g.If(isAdmin, Span(Class("ref-actions"),
								branchRenameDetails(repo, b),
								g.If(b.Name != repo.DefaultBranch, branchDeleteDetails(repo, b)),
							)),
						),
						Div(Class("ref-meta-row"),
							g.If(b.AuthorName != "", Span(Class("ref-author"), g.Text(b.AuthorName))),
							g.If(b.ShortHash != "",
								A(Href("/"+repo.Name+"/commit/"+b.ShortHash), Class("ref-hash mono"),
									g.Text(b.ShortHash))),
							g.If(b.Subject != "", Span(Class("ref-subject"), g.Text(b.Subject))),
							g.If(b.Date != "", Time(Class("ref-date"), DateTime(b.Date),
								g.Text(util.FormatDateTime(b.Date)))),
						),
					)
				}),
			)),
			Pagination(page),
		),
	)
}

func branchRenameDetails(repo *db.Repo, b gitcmd.BranchInfo) g.Node {
	return Details(Class("confirm-details confirm-details-inline"),
		Summary(Class("btn btn-sm"), g.Text("Rename")),
		Div(Class("confirm-popup"),
			Form(Method("POST"), Action("/"+repo.Name+"/branches/rename"), Class("popup-form"),
				Input(Type("hidden"), Name("old_name"), Value(b.Name)),
				Input(Name("new_name"), Type("text"), Required(), Placeholder("new-name"),
					Value(b.Name), MaxLength(strconv.Itoa(maxBranchNameLength))),
				Button(Type("submit"), Class("btn btn-sm btn-primary"), g.Text("Rename")),
			),
		),
	)
}

func branchDeleteDetails(repo *db.Repo, b gitcmd.BranchInfo) g.Node {
	return Details(Class("confirm-details confirm-details-inline"),
		Summary(Class("btn btn-sm btn-danger"), g.Text("Delete")),
		Div(Class("confirm-popup"),
			g.Text("Delete branch "), Strong(g.Text(b.Name)), g.Text("?"),
			Form(Method("POST"), Action("/"+repo.Name+"/branches/delete"), Class("inline-form"),
				Input(Type("hidden"), Name("name"), Value(b.Name)),
				Button(Type("submit"), Class("btn btn-sm btn-danger"), g.Text("Yes, delete")),
			),
		),
	)
}

// TagList renders the tag overview. tagReleases maps a tag name to the id of
// the release that references it.
func TagList(cfg *config.Config, user *db.SessionUser, repo *db.Repo, tags []gitcmd.TagInfo,
	tagReleases map[string]int64, page PageInfo, success, errMsg string,
) g.Node {
	isAdmin := user != nil && user.IsAdmin
	return Layout(Page{Title: "Tags — " + repo.Name, User: user, Cfg: cfg},
		Div(Class("container"),
			RepoHeader(repo),
			RepoNav(repo, "tags", user),
			g.If(success != "", P(Class("form-success"), g.Text(success))),
			g.If(errMsg != "", P(Class("form-error"), g.Text(errMsg))),
			Div(Class("list-header"),
				H2(Class("list-heading"), g.Text("Tags")),
				g.If(isAdmin, Details(Class("confirm-details"),
					Summary(Class("btn btn-primary btn-sm"), g.Text("New tag")),
					Div(Class("confirm-popup confirm-popup-form"),
						Form(Method("POST"), Action("/"+repo.Name+"/tags/create"), Class("popup-form"),
							Div(Class("form-group"),
								Label(For("new-tag-name"), g.Text("Tag name")),
								Input(ID("new-tag-name"), Name("name"), Type("text"), Required(),
									Placeholder("v1.0.0"), MaxLength(strconv.Itoa(maxTagNameLength))),
							),
							Div(Class("form-group"),
								Label(For("new-tag-ref"), g.Text("Target")),
								Input(ID("new-tag-ref"), Name("ref"), Type("text"), Required(),
									Value(repo.DefaultBranch), Placeholder("branch, tag, or commit"),
									MaxLength(strconv.Itoa(maxTagNameLength))),
							),
							Div(Class("form-group"),
								Label(For("new-tag-message"), g.Text("Message "),
									Span(Class("text-muted"), g.Text("(blank = lightweight)"))),
								Input(ID("new-tag-message"), Name("message"), Type("text"),
									Placeholder("Optional tag message"),
									MaxLength(strconv.Itoa(maxTagMessageLength))),
							),
							Button(Type("submit"), Class("btn btn-primary btn-sm"), g.Text("Create tag")),
						),
					),
				)),
			),
			g.If(len(tags) == 0, Div(Class("empty-state"), P(g.Text("No tags yet.")))),
			g.If(len(tags) > 0, Ul(Class("ref-list"),
				g.Map(tags, func(tag gitcmd.TagInfo) g.Node {
					releaseID := tagReleases[tag.Name]
					releaseHref := "/" + repo.Name + "/releases/" + strconv.FormatInt(releaseID, 10)
					return Li(Class("ref-item"),
						Div(Class("ref-name-row"),
							A(Href("/"+repo.Name+"/tree/"+EscapePath(tag.Name)), Class("ref-name"), g.Text(tag.Name)),
							g.If(releaseID != 0,
								A(Href(releaseHref), Class("badge badge-release"), g.Text("release"))),
							g.If(isAdmin, Span(Class("ref-actions"),
								tagDeleteDetails(repo, tag, releaseID, releaseHref))),
						),
						Div(Class("ref-meta-row"),
							g.If(tag.TaggerName != "", Span(Class("ref-author"), g.Text(tag.TaggerName))),
							g.If(tag.ShortHash != "",
								A(Href("/"+repo.Name+"/commit/"+tag.ShortHash), Class("ref-hash mono"),
									g.Text(tag.ShortHash))),
							g.If(tag.Subject != "", Span(Class("ref-subject"), g.Text(tag.Subject))),
							g.If(tag.Date != "", Time(Class("ref-date"), DateTime(tag.Date),
								g.Text(util.FormatDateTime(tag.Date)))),
						),
					)
				}),
			)),
			Pagination(page),
		),
	)
}

func tagDeleteDetails(repo *db.Repo, tag gitcmd.TagInfo, releaseID int64, releaseHref string) g.Node {
	return Details(Class("confirm-details confirm-details-inline"),
		Summary(Class("btn btn-sm btn-danger"), g.Text("Delete")),
		Div(Class("confirm-popup"),
			g.If(releaseID != 0, P(Class("confirm-warning"),
				g.Text("Tag "), Strong(g.Text(tag.Name)), g.Text(" is linked to "),
				A(Href(releaseHref), g.Text("a release")),
				g.Text(". Only the git tag will be deleted; the release record will remain."),
			)),
			g.If(releaseID == 0, g.Group{
				g.Text("Delete tag "), Strong(g.Text(tag.Name)), g.Text("?"),
			}),
			Form(Method("POST"), Action("/"+repo.Name+"/tags/delete"), Class("inline-form"),
				Input(Type("hidden"), Name("name"), Value(tag.Name)),
				Button(Type("submit"), Class("btn btn-sm btn-danger"), g.Text("Yes, delete")),
			),
		),
	)
}