package views

import (
	"strconv"
	"strings"

	"hearthforge/internal/config"
	"hearthforge/internal/db"
	"hearthforge/internal/util"

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

// deref returns the string a pointer holds, or "" for nil.
func deref(s *string) string {
	if s == nil {
		return ""
	}
	return *s
}

// RepoList renders the repository index with search, sort and pagination.
func RepoList(cfg *config.Config, user *db.SessionUser, repos []db.Repo,
	search, sort string, page PageInfo,
) g.Node {
	return Layout(Page{Title: "Repositories", User: user, Cfg: cfg},
		Div(Class("container"),
			Div(Class("page-header"),
				H1(Class("page-title"), g.Text("Repositories")),
				g.If(user != nil && user.IsAdmin,
					A(Href("/new"), Class("btn btn-primary"), g.Text("New repository"))),
			),
			Div(Class("search-row"),
				Form(Method("GET"), Action("/"), Class("search-form"),
					Div(Class("search-input-wrap"),
						Input(Type("search"), Name("q"), Value(search),
							Placeholder("Search repositories…"), Class("search-input"),
							AutoComplete("off")),
						Button(Type("submit"), Class("btn btn-sm"), g.Text("Search")),
					),
				),
				Form(Method("POST"), Action("/sort"),
					Select(Name("sort"), Class("repo-sort-select"), g.Attr("data-autosubmit"),
						Option(Value("created"), g.If(sort == "created", Selected()),
							g.Text("Newest first")),
						Option(Value("name"), g.If(sort == "name", Selected()),
							g.Text("Name (A–Z)")),
					),
					NoScript(Button(Type("submit"), Class("btn btn-sm"), g.Text("Go"))),
				),
			),
			g.If(len(repos) == 0, Div(Class("empty-state"),
				g.If(search != "", P(g.Text("No repositories match "), Strong(g.Text(search)), g.Text("."))),
				g.If(search == "", P(g.Text("No repositories yet."))),
			)),
			g.If(len(repos) > 0, Ul(Class("repo-list"),
				g.Map(repos, func(repo db.Repo) g.Node {
					return Li(Class("repo-card"),
						Div(Class("repo-card-main"),
							Div(Class("repo-card-title"),
								A(Href("/"+repo.Name), Class("repo-name"), g.Text(repo.Name)),
								g.If(repo.IsPinned, Span(Class("badge badge-pinned"), g.Text("Pinned"))),
								g.If(repo.IsPrivate, Span(Class("badge badge-private"), g.Text("Private"))),
							),
							g.If(deref(repo.Description) != "",
								P(Class("repo-description"), g.Text(deref(repo.Description)))),
						),
						Div(Class("repo-card-meta"),
							g.El("time", Class("repo-date"), DateTime(repo.CreatedAt),
								g.Text(util.FormatDate(repo.CreatedAt))),
						),
					)
				}),
			)),
			Pagination(page),
		),
	)
}

// NewRepo renders the repository creation form.
func NewRepo(cfg *config.Config, user *db.SessionUser, errMsg string) g.Node {
	return Layout(Page{Title: "New repository", User: user, Cfg: cfg},
		Div(Class("container container-narrow"),
			H1(Class("page-title"), g.Text("Create new repository")),
			g.If(errMsg != "", P(Class("form-error"), g.Text(errMsg))),
			Form(Method("POST"), Action("/new"), Class("form-card"),
				Div(Class("form-group"),
					Label(For("name"), g.Text("Repository name")),
					Input(ID("name"), Name("name"), Type("text"), Required(),
						Pattern("[a-zA-Z0-9._-]+"),
						Title("Letters, numbers, dots, hyphens, underscores"),
						Placeholder("my-project")),
				),
				Div(Class("form-group"),
					Label(For("description"), g.Text("Description "),
						Span(Class("text-muted"), g.Text("(optional)"))),
					Input(ID("description"), Name("description"), Type("text"),
						Placeholder("A short description")),
				),
				Div(Class("form-group"),
					Label(For("default_branch"), g.Text("Default branch")),
					Input(ID("default_branch"), Name("default_branch"), Type("text"),
						Value("main"), Placeholder("main")),
				),
				Div(Class("form-group"),
					Label(Class("checkbox-label"),
						Input(Type("checkbox"), Name("is_private"), Value("1")),
						g.Text("Private repository (only visible to you)")),
				),
				Button(Type("submit"), Class("btn btn-primary"), g.Text("Create repository")),
			),
		),
	)
}

// RepoHeader renders the repository name and its private badge.
func RepoHeader(repo *db.Repo) g.Node {
	return Div(Class("repo-header"),
		Div(Class("repo-title-row"),
			H1(Class("page-title"), A(Href("/"+repo.Name), g.Text(repo.Name))),
			g.If(repo.IsPrivate, Span(Class("badge badge-private"), g.Text("Private"))),
		),
	)
}

// RepoNav renders the repository tab bar. active is the key of the current tab,
// one of code, branches, tags, commits, issues, patches, releases, ci, settings.
func RepoNav(repo *db.Repo, active string, user *db.SessionUser) g.Node {
	tabs := []struct{ key, label, href string }{
		{"code", "Code", "/" + repo.Name},
		{"branches", "Branches", "/" + repo.Name + "/branches"},
		{"tags", "Tags", "/" + repo.Name + "/tags"},
		{"commits", "Commits", "/" + repo.Name + "/commits/" + EscapePath(repo.DefaultBranch)},
		{"issues", "Issues", "/" + repo.Name + "/issues"},
		{"patches", "Patches", "/" + repo.Name + "/patches"},
		{"releases", "Releases", "/" + repo.Name + "/releases"},
		{"ci", "Pipelines", "/" + repo.Name + "/ci"},
	}
	tabClass := func(key string) string {
		if active == key {
			return "repo-tab active"
		}
		return "repo-tab"
	}
	return Div(Class("repo-nav-bar"),
		Nav(Class("repo-tabs"),
			g.Map(tabs, func(t struct{ key, label, href string }) g.Node {
				return A(Href(t.href), Class(tabClass(t.key)), g.Text(t.label))
			}),
			g.If(user != nil && user.IsAdmin,
				A(Href("/"+repo.Name+"/settings"), Class(tabClass("settings")), g.Text("Settings"))),
		),
	)
}

// BranchSelector renders the ref switcher. view is tree, commits or blob.
// path is the subpath for tree and the file path for blob.
func BranchSelector(repoName string, branches, tags []string, currentRef, view, path string) g.Node {
	if len(branches) == 0 && len(tags) == 0 {
		return nil
	}
	isDetached := !slicesContains(branches, currentRef) && !slicesContains(tags, currentRef)
	shortRef := currentRef
	if isDetached && len(currentRef) > 8 {
		shortRef = currentRef[:8]
	}
	return Form(Method("GET"), Action("/"+repoName+"/branch-switch"), Class("branch-selector"),
		Input(Type("hidden"), Name("view"), Value(view)),
		g.If(path != "", Input(Type("hidden"), Name("path"), Value(path))),
		Span(Class("branch-selector-icon"), g.Text("⎇")),
		Select(Name("rev"), Class("branch-select"), g.Attr("data-autosubmit"),
			g.If(isDetached,
				Option(Value(currentRef), Selected(), g.Text(shortRef+" (detached)"))),
			OptGroup(LabelAttr("Branches"),
				g.Map(branches, func(b string) g.Node {
					return Option(Value(b), g.If(b == currentRef, Selected()), g.Text(b))
				}),
			),
			g.If(len(tags) > 0, OptGroup(LabelAttr("Tags"),
				g.Map(tags, func(t string) g.Node {
					return Option(Value(t), g.If(t == currentRef, Selected()), g.Text(t))
				}),
			)),
		),
		NoScript(Button(Type("submit"), Class("btn btn-sm"), g.Text("Go"))),
	)
}

func slicesContains(list []string, want string) bool {
	for _, v := range list {
		if v == want {
			return true
		}
	}
	return false
}

// escapeRegexp escapes the characters the HTML pattern attribute treats as
// regular expression syntax.
func escapeRegexp(s string) string {
	var b strings.Builder
	for _, r := range s {
		if strings.ContainsRune(`.*+?^${}()|[]\`, r) {
			b.WriteRune('\\')
		}
		b.WriteRune(r)
	}
	return b.String()
}

// RepoSettings renders the repository settings page.
func RepoSettings(cfg *config.Config, user *db.SessionUser, repo *db.Repo, branches []string,
	labels []db.Label, secrets []db.CiSecret, success, errMsg string,
) g.Node {
	return Layout(Page{Title: "Settings — " + repo.Name, User: user, Cfg: cfg},
		Div(Class("container"),
			RepoHeader(repo),
			RepoNav(repo, "settings", user),
			g.If(success != "", P(Class("form-success"), g.Text(success))),
			g.If(errMsg != "", P(Class("form-error"), g.Text(errMsg))),
			Form(Method("POST"), Action("/"+repo.Name+"/settings"), Class("form-card"),
				Div(Class("form-group"),
					Label(For("description"), g.Text("Description")),
					Input(ID("description"), Name("description"), Type("text"),
						Value(deref(repo.Description)), Placeholder("A short description")),
				),
				Div(Class("form-group"),
					Label(For("default_branch"), g.Text("Default branch")),
					g.If(len(branches) > 0,
						Select(ID("default_branch"), Name("default_branch"), Class("branch-select"),
							g.Map(branches, func(b string) g.Node {
								return Option(Value(b), g.If(b == repo.DefaultBranch, Selected()), g.Text(b))
							}),
						)),
					g.If(len(branches) == 0,
						P(Class("form-hint"),
							g.Text("No branches yet — push your first commit to set the default branch."))),
				),
				Div(Class("form-group"),
					Label(Class("checkbox-label"),
						Input(Type("checkbox"), Name("is_private"), Value("1"),
							g.If(repo.IsPrivate, Checked())),
						g.Text("Private repository (only visible to you)")),
				),
				Div(Class("form-group"),
					Label(Class("checkbox-label"),
						Input(Type("checkbox"), Name("is_pinned"), Value("1"),
							g.If(repo.IsPinned, Checked())),
						g.Text("Pin this repository (always shown at the top of the list)")),
				),
				Div(Class("form-group"),
					Label(Class("checkbox-label"),
						Input(Type("checkbox"), Name("allow_user_labels"), Value("1"),
							g.If(repo.AllowUserLabels, Checked())),
						g.Text("Allow users to add/remove labels on their own issues and patches")),
				),
				Div(Class("form-group"),
					Label(For("issue_template"), g.Text("Issue template "),
						Span(Class("text-muted"), g.Text("(Markdown, prefilled when opening a new issue)"))),
					Textarea(ID("issue_template"), Name("issue_template"), Rows("8"),
						Placeholder("## Description\n\n## Steps to reproduce\n\n## Expected behavior"),
						g.Text(deref(repo.IssueTemplate))),
				),
				Div(Class("form-group"),
					Label(For("patch_template"), g.Text("Patch template "),
						Span(Class("text-muted"), g.Text("(Markdown, prefilled when submitting a new patch)"))),
					Textarea(ID("patch_template"), Name("patch_template"), Rows("8"),
						Placeholder("## Summary\n\n## Testing"),
						g.Text(deref(repo.PatchTemplate))),
				),
				Button(Type("submit"), Class("btn btn-primary"), g.Text("Save settings")),
			),
			repoLabelsCard(repo, labels),
			repoSecretsCard(repo, secrets),
			repoDangerZone(repo),
		),
	)
}

func repoLabelsCard(repo *db.Repo, labels []db.Label) g.Node {
	return Div(Class("form-card"),
		H2(Class("section-title"), g.Text("Labels")),
		g.If(len(labels) > 0, Div(Class("label-settings-list"),
			g.Map(labels, func(label db.Label) g.Node {
				return Div(Class("label-settings-item"),
					Span(Class("label-settings-swatch"), Style("background:"+label.Color)),
					Span(Class("label-settings-name"), g.Text(label.Name)),
					Form(Method("POST"), Action("/"+repo.Name+"/settings/labels/delete"),
						Input(Type("hidden"), Name("id"), Value(strconv.FormatInt(label.ID, 10))),
						Button(Class("btn btn-danger btn-sm"), Type("submit"), g.Text("Delete")),
					),
				)
			}),
		)),
		Form(Method("POST"), Action("/"+repo.Name+"/settings/labels"), Class("label-add-form"),
			Input(Class("form-input label-name-input"), Type("text"), Name("name"),
				Placeholder("Label name"), MaxLength("50"), Required()),
			Label(Class("label-color-swatch-label"), Title("Pick a color"),
				Input(Type("color"), Name("color"), Value("#808080"), Class("label-color-input")),
			),
			Button(Type("submit"), Class("btn btn-secondary btn-sm"), g.Text("Add label")),
		),
	)
}

func repoSecretsCard(repo *db.Repo, secrets []db.CiSecret) g.Node {
	return Div(Class("form-card"),
		H2(Class("section-title"), g.Text("CI Secrets")),
		P(Class("text-muted"), Style("font-size: var(--text-sm); margin-bottom: var(--space-3)"),
			g.Text("Secrets are injected as environment variables into pipeline runs and masked in logs. Values are write-only — they cannot be retrieved after saving.")),
		g.If(len(secrets) > 0, Div(Class("label-settings-list"),
			g.Map(secrets, func(secret db.CiSecret) g.Node {
				return Div(Class("label-settings-item"),
					Span(Class("label-settings-name"), Code(g.Text(secret.Name))),
					g.If(deref(secret.Description) != "",
						Span(Class("text-muted"), g.Text(deref(secret.Description)))),
					Span(Class("text-muted"), g.Text("●●●●●●")),
					Form(Method("POST"), Action("/"+repo.Name+"/settings/ci-secrets/delete"),
						Input(Type("hidden"), Name("id"), Value(strconv.FormatInt(secret.ID, 10))),
						Button(Class("btn btn-danger btn-sm"), Type("submit"), g.Text("Delete")),
					),
				)
			}),
		)),
		Form(Method("POST"), Action("/"+repo.Name+"/settings/ci-secrets"), Class("label-add-form"),
			Input(Class("form-input label-name-input"), Type("text"), Name("name"),
				Placeholder("SECRET_NAME"), Pattern("[A-Za-z_][A-Za-z0-9_]*"), Required()),
			Input(Class("form-input label-name-input"), Type("password"), Name("value"),
				Placeholder("Value"), AutoComplete("off"), Required()),
			Input(Class("form-input label-name-input"), Type("text"), Name("description"),
				Placeholder("Description (optional)")),
			Button(Type("submit"), Class("btn btn-secondary btn-sm"), g.Text("Save secret")),
		),
	)
}

func repoDangerZone(repo *db.Repo) g.Node {
	return Div(Class("danger-zone"),
		H2(Class("section-title danger-title"), g.Text("Danger zone")),
		Div(Class("form-card danger-card"),
			Div(Class("danger-item"),
				Div(Class("danger-item-info"),
					Strong(g.Text("Rename this repository")),
					P(Class("text-muted"),
						g.Text("Changing the name breaks existing clone URLs and links to this repo. Collaborators will need to update their remotes.")),
				),
				Form(Method("POST"), Action("/"+repo.Name+"/settings/rename"), Class("danger-form"),
					Div(Class("form-group"),
						Label(For("new_name"), g.Text("New name")),
						Input(ID("new_name"), Name("new_name"), Type("text"), Required(),
							Pattern(`[A-Za-z0-9._\-]+`), AutoComplete("off")),
					),
					Details(Class("confirm-details"),
						Summary(Class("btn btn-danger"), g.Text("Rename repository")),
						Div(Class("confirm-popup"),
							g.Text("Rename "), Span(g.Text(repo.Name)), g.Text("?"),
							Button(Type("submit"), Class("btn btn-danger"), g.Text("Yes, rename")),
						),
					),
				),
			),
			Div(Class("danger-item"),
				Div(Class("danger-item-info"),
					Strong(g.Text("Delete this repository")),
					P(Class("text-muted"), g.Text("Once deleted, there is no going back.")),
				),
				Form(Method("POST"), Action("/"+repo.Name+"/settings/delete"), Class("danger-form"),
					Div(Class("form-group"),
						Label(For("confirm_delete"),
							g.Text("Type "), Code(g.Text(repo.Name)), g.Text(" to confirm deletion")),
						Input(ID("confirm_delete"), Name("confirm_name"), Type("text"), Required(),
							Pattern(escapeRegexp(repo.Name)), AutoComplete("off")),
					),
					Details(Class("confirm-details"),
						Summary(Class("btn btn-danger"), g.Text("Delete repository")),
						Div(Class("confirm-popup"),
							g.Text("Delete "), Span(g.Text(repo.Name)), g.Text("? This cannot be undone."),
							Button(Type("submit"), Class("btn btn-danger"), g.Text("Yes, delete")),
						),
					),
				),
			),
		),
	)
}