package beads

import (
	"context"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

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

// 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{
		rowsByTable: map[string]*browse.RowPage{
			"issues":          issues,
			"labels":          labels,
			"dependencies":    deps,
			"custom_statuses": statuses,
		},
	}
}

func TestMilestonesBuild(t *testing.T) {
	d, err := BuildMilestones(context.Background(), milestoneFixture(), "main")
	require.NoError(t, err)

	require.Len(t, d.Milestones, 2, "milestones = %+v", d.Milestones)
	assert.Equal(t, 1, d.Unlabeled)
	assert.Equal(t, 6, d.Total)

	m1 := d.Milestones[0]
	assert.Equal(t, "m1", m1.Name)
	assert.Equal(t, 4, m1.Total)
	assert.Equal(t, 1, m1.Done)
	assert.Equal(t, 3, m1.Open)
	assert.Equal(t, 25, m1.Pct())
	// Hierarchy: the milestone-typed issue heads the list, the epic nests its
	// subtask, and the bug (whose only dep edge is "blocks") stays loose.
	require.Len(t, m1.Heads, 1, "m1 heads = %+v", m1.Heads)
	assert.Equal(t, "i-m", m1.Heads[0].ID)
	require.Len(t, m1.Epics, 1, "m1 epics = %+v", m1.Epics)
	epic := m1.Epics[0]
	assert.Equal(t, "i-e", epic.Card.ID)
	require.Len(t, epic.Children, 1, "epic = %+v", epic)
	assert.Equal(t, "i-a", epic.Children[0].ID)
	assert.Equal(t, 1, epic.Done)
	assert.Equal(t, 1, epic.Total)
	assert.Equal(t, "closed", epic.Children[0].Category, "i-a should be closed")
	require.Len(t, m1.Loose, 1, "m1 loose = %+v", m1.Loose)
	assert.Equal(t, "i-b", m1.Loose[0].ID)

	m2 := d.Milestones[1]
	assert.Equal(t, "m2", m2.Name)
	assert.Equal(t, 1, m2.Total)
	assert.Equal(t, 0, m2.Done)
	assert.Empty(t, m2.Heads)
	assert.Empty(t, m2.Epics)
	require.Len(t, m2.Loose, 1, "m2 hierarchy = %+v", m2)
	assert.Equal(t, "i-c", m2.Loose[0].ID)
}

// TestMilestonesEmpty: a beads DB with no milestone labels still produces a
// (empty) rollup rather than erroring — the tab renders an empty state.
func TestMilestonesEmpty(t *testing.T) {
	d, err := BuildMilestones(context.Background(), beadsFixture(), "main")
	require.NoError(t, err)
	assert.Empty(t, d.Milestones, "expected no milestones")
	assert.Equal(t, d.Total, d.Unlabeled,
		"with no milestone labels all issues are unlabeled")
}