package web

import (
	"context"
	"net/http"
	"net/url"
	"strings"
	"testing"

	"sourcecraft.dev/bigbes/sr-ht-dolt/browse"
	"sourcecraft.dev/bigbes/sr-ht-dolt/core"
)

// milestoneFixture: six issues across two milestones. m1 carries the full
// hierarchy — a milestone-typed head, an epic with one (closed) subtask, and a
// loose bug; m2 has a single loose feature; one issue has no milestone label.
func milestoneFixture() *fakeSession {
	issues := &browse.RowPage{
		Columns: []string{"id", "title", "status", "priority", "issue_type", "assignee"},
		Rows: [][]string{
			{"i-m", "Mike", "open", "0", "milestone", ""},
			{"i-e", "Echo", "open", "1", "epic", ""},
			{"i-a", "Alpha", "closed", "1", "task", "alice"}, // subtask of i-e
			{"i-b", "Bravo", "open", "0", "bug", "bob"},
			{"i-c", "Charlie", "open", "2", "feature", ""},
			{"i-d", "Delta", "open", "1", "task", ""}, // no milestone
		},
		Total: 6,
	}
	labels := &browse.RowPage{
		Columns: []string{"issue_id", "label"},
		Rows: [][]string{
			{"i-m", "milestone:m1"},
			{"i-e", "milestone:m1"},
			{"i-a", "milestone:m1"},
			{"i-b", "milestone:m1"},
			{"i-c", "milestone:m2"},
			{"i-b", "backend"}, // non-milestone label ignored by grouping
		},
		Total: 6,
	}
	deps := &browse.RowPage{
		Columns: []string{"issue_id", "depends_on_issue_id", "type"},
		Rows: [][]string{
			{"i-a", "i-e", "parent-child"},
			{"i-b", "i-a", "blocks"}, // non-hierarchy edge ignored by nesting
		},
		Total: 2,
	}
	statuses := &browse.RowPage{
		Columns: []string{"name", "category"},
		Rows:    [][]string{{"open", "open"}, {"closed", "closed"}},
		Total:   2,
	}
	return &fakeSession{
		branches: []browse.Branch{{Name: "main", Head: "abcdef1234567890"}},
		tables:   beadsTables(),
		rowsByTable: map[string]*browse.RowPage{
			"issues":          issues,
			"labels":          labels,
			"dependencies":    deps,
			"custom_statuses": statuses,
		},
	}
}

func TestMilestonesApplies(t *testing.T) {
	// The milestone tab appears exactly where the beads tab does.
	if (&milestonesView{}).Applies(beadsTables()) != (&beadsView{}).Applies(beadsTables()) {
		t.Fatalf("milestones Applies should mirror beads Applies")
	}
	if (&milestonesView{}).Applies([]browse.TableInfo{{Name: "widgets"}}) {
		t.Fatalf("milestones should not apply to an unrelated schema")
	}
}

func TestMilestonesBuild(t *testing.T) {
	got, err := (&milestonesView{}).Build(context.Background(), milestoneFixture(), nil, "main", url.Values{})
	if err != nil {
		t.Fatalf("Build: %v", err)
	}
	d := got.(*MilestoneView)

	if len(d.Milestones) != 2 {
		t.Fatalf("milestones = %d, want 2: %+v", len(d.Milestones), d.Milestones)
	}
	if d.Unlabeled != 1 || d.Total != 6 {
		t.Errorf("unlabeled=%d total=%d, want 1 and 6", d.Unlabeled, d.Total)
	}
	m1 := d.Milestones[0]
	if m1.Name != "m1" || m1.Total != 4 || m1.Done != 1 || m1.Open != 3 || m1.Pct() != 25 {
		t.Errorf("m1 = %+v, want name m1 total 4 done 1 open 3 pct 25", m1)
	}
	// Hierarchy: the milestone-typed issue heads the list, the epic nests its
	// subtask, and the bug (whose only dep edge is "blocks") stays loose.
	if len(m1.Heads) != 1 || m1.Heads[0].ID != "i-m" {
		t.Errorf("m1 heads = %+v, want [i-m]", m1.Heads)
	}
	if len(m1.Epics) != 1 || m1.Epics[0].Card.ID != "i-e" {
		t.Fatalf("m1 epics = %+v, want [i-e]", m1.Epics)
	}
	epic := m1.Epics[0]
	if len(epic.Children) != 1 || epic.Children[0].ID != "i-a" || epic.Done != 1 || epic.Total != 1 {
		t.Errorf("epic = %+v, want child i-a and rollup 1/1", epic)
	}
	if epic.Children[0].Category != "closed" {
		t.Errorf("i-a should be closed: %+v", epic.Children[0])
	}
	if len(m1.Loose) != 1 || m1.Loose[0].ID != "i-b" {
		t.Errorf("m1 loose = %+v, want [i-b]", m1.Loose)
	}
	m2 := d.Milestones[1]
	if m2.Name != "m2" || m2.Total != 1 || m2.Done != 0 {
		t.Errorf("m2 = %+v", m2)
	}
	if len(m2.Heads) != 0 || len(m2.Epics) != 0 || len(m2.Loose) != 1 || m2.Loose[0].ID != "i-c" {
		t.Errorf("m2 hierarchy = %+v, want only loose [i-c]", m2)
	}
}

func TestMilestonesRender(t *testing.T) {
	h := newHarness(t)
	h.store.add(&core.Repo{Name: "db", OwnerID: 1, OwnerName: "alice", Path: "/d", Visibility: core.VisibilityPublic})
	h.browse.sess = milestoneFixture()
	setViews(t, h, &beadsView{}, &milestonesView{})

	rec := h.do("GET", "/~alice/db/view/milestones", nil, nil)
	if rec.Code != http.StatusOK {
		t.Fatalf("milestones view: got %d; body=%s", rec.Code, rec.Body.String())
	}
	body := rec.Body.String()
	for _, want := range []string{
		"· milestones",         // page heading
		"ms-title\">m1<",              // milestone name
		"1</b>/4 done",                // rollup counts
		"ms-issue head",               // the milestone-typed issue leads the list
		"ms-issue epic",               // the epic row
		"ms-issue child done",         // its subtask, nested and closed
		`class="r-sub">1/1<`,          // the epic's subtask rollup
		"Charlie",                     // an issue under m2
		"carry no milestone",          // unlabeled footnote
		`view/milestones">Milestones`, // the tab link
		"nav-link active",             // the active tab marker
	} {
		if !strings.Contains(body, want) {
			t.Errorf("milestones render missing %q", want)
		}
	}
}

// TestMilestonesEmpty: a beads DB with no milestone labels still gets the tab,
// showing an empty state rather than erroring.
func TestMilestonesEmpty(t *testing.T) {
	got, err := (&milestonesView{}).Build(context.Background(), beadsFixture(), nil, "main", url.Values{})
	if err != nil {
		t.Fatalf("Build: %v", err)
	}
	d := got.(*MilestoneView)
	if len(d.Milestones) != 0 {
		t.Errorf("expected no milestones, got %+v", d.Milestones)
	}
	if d.Unlabeled != d.Total {
		t.Errorf("with no milestone labels all issues are unlabeled; got %d/%d", d.Unlabeled, d.Total)
	}
}