package beads

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

// TestNew verifies the constructor.
func TestNew(t *testing.T) {
	b := New("/some/path")
	if b == nil {
		t.Fatal("New returned nil")
	}
	if b.workDir != "/some/path" {
		t.Errorf("workDir = %q, want /some/path", b.workDir)
	}
}

// TestListOptions verifies ListOptions defaults.
func TestListOptions(t *testing.T) {
	opts := ListOptions{
		Status:   "open",
		Type:     "task",
		Priority: 1,
	}
	if opts.Status != "open" {
		t.Errorf("Status = %q, want open", opts.Status)
	}
}

// TestCreateOptions verifies CreateOptions fields.
func TestCreateOptions(t *testing.T) {
	opts := CreateOptions{
		Title:       "Test issue",
		Type:        "task",
		Priority:    2,
		Description: "A test description",
		Parent:      "gt-abc",
	}
	if opts.Title != "Test issue" {
		t.Errorf("Title = %q, want 'Test issue'", opts.Title)
	}
	if opts.Parent != "gt-abc" {
		t.Errorf("Parent = %q, want gt-abc", opts.Parent)
	}
}

// TestUpdateOptions verifies UpdateOptions pointer fields.
func TestUpdateOptions(t *testing.T) {
	status := "in_progress"
	priority := 1
	opts := UpdateOptions{
		Status:   &status,
		Priority: &priority,
	}
	if *opts.Status != "in_progress" {
		t.Errorf("Status = %q, want in_progress", *opts.Status)
	}
	if *opts.Priority != 1 {
		t.Errorf("Priority = %d, want 1", *opts.Priority)
	}
}

// TestIsBeadsRepo tests repository detection.
func TestIsBeadsRepo(t *testing.T) {
	// Test with a non-beads directory
	tmpDir, err := os.MkdirTemp("", "beads-test-*")
	if err != nil {
		t.Fatal(err)
	}
	defer func() { _ = os.RemoveAll(tmpDir) }()

	b := New(tmpDir)
	// This should return false since there's no .beads directory
	// and bd list will fail
	if b.IsBeadsRepo() {
		// This might pass if bd handles missing .beads gracefully
		t.Log("IsBeadsRepo returned true for non-beads directory (bd might initialize)")
	}
}

// TestWrapError tests error wrapping.
func TestWrapError(t *testing.T) {
	b := New("/test")

	tests := []struct {
		stderr   string
		wantErr  error
		wantNil  bool
	}{
		{"not a beads repository", ErrNotARepo, false},
		{"No .beads directory found", ErrNotARepo, false},
		{".beads directory not found", ErrNotARepo, false},
		{"sync conflict detected", ErrSyncConflict, false},
		{"CONFLICT in file.md", ErrSyncConflict, false},
		{"Issue not found: gt-xyz", ErrNotFound, false},
		{"gt-xyz not found", ErrNotFound, false},
	}

	for _, tt := range tests {
		err := b.wrapError(nil, tt.stderr, []string{"test"})
		if tt.wantNil {
			if err != nil {
				t.Errorf("wrapError(%q) = %v, want nil", tt.stderr, err)
			}
		} else {
			if err != tt.wantErr {
				t.Errorf("wrapError(%q) = %v, want %v", tt.stderr, err, tt.wantErr)
			}
		}
	}
}

// Integration test that runs against real bd if available
func TestIntegration(t *testing.T) {
	if testing.Short() {
		t.Skip("skipping integration test in short mode")
	}

	// Find a beads repo (use current directory if it has .beads)
	cwd, err := os.Getwd()
	if err != nil {
		t.Fatal(err)
	}

	// Walk up to find .beads
	dir := cwd
	for {
		if _, err := os.Stat(filepath.Join(dir, ".beads")); err == nil {
			break
		}
		parent := filepath.Dir(dir)
		if parent == dir {
			t.Skip("no .beads directory found in path")
		}
		dir = parent
	}

	b := New(dir)

	// Test List
	t.Run("List", func(t *testing.T) {
		issues, err := b.List(ListOptions{Status: "open"})
		if err != nil {
			t.Fatalf("List failed: %v", err)
		}
		t.Logf("Found %d open issues", len(issues))
	})

	// Test Ready
	t.Run("Ready", func(t *testing.T) {
		issues, err := b.Ready()
		if err != nil {
			t.Fatalf("Ready failed: %v", err)
		}
		t.Logf("Found %d ready issues", len(issues))
	})

	// Test Blocked
	t.Run("Blocked", func(t *testing.T) {
		issues, err := b.Blocked()
		if err != nil {
			t.Fatalf("Blocked failed: %v", err)
		}
		t.Logf("Found %d blocked issues", len(issues))
	})

	// Test Show (if we have issues)
	t.Run("Show", func(t *testing.T) {
		issues, err := b.List(ListOptions{})
		if err != nil {
			t.Fatalf("List failed: %v", err)
		}
		if len(issues) == 0 {
			t.Skip("no issues to show")
		}

		issue, err := b.Show(issues[0].ID)
		if err != nil {
			t.Fatalf("Show(%s) failed: %v", issues[0].ID, err)
		}
		t.Logf("Showed issue: %s - %s", issue.ID, issue.Title)
	})
}

// TestParseMRFields tests parsing MR fields from issue descriptions.
func TestParseMRFields(t *testing.T) {
	tests := []struct {
		name        string
		issue       *Issue
		wantNil     bool
		wantFields  *MRFields
	}{
		{
			name:    "nil issue",
			issue:   nil,
			wantNil: true,
		},
		{
			name:    "empty description",
			issue:   &Issue{Description: ""},
			wantNil: true,
		},
		{
			name:    "no MR fields",
			issue:   &Issue{Description: "This is just plain text\nwith no field markers"},
			wantNil: true,
		},
		{
			name: "all fields",
			issue: &Issue{
				Description: `branch: polecat/Nux/gt-xyz
target: main
source_issue: gt-xyz
worker: Nux
rig: gastown
merge_commit: abc123def
close_reason: merged`,
			},
			wantFields: &MRFields{
				Branch:      "polecat/Nux/gt-xyz",
				Target:      "main",
				SourceIssue: "gt-xyz",
				Worker:      "Nux",
				Rig:         "gastown",
				MergeCommit: "abc123def",
				CloseReason: "merged",
			},
		},
		{
			name: "partial fields",
			issue: &Issue{
				Description: `branch: polecat/Toast/gt-abc
target: integration/gt-epic
source_issue: gt-abc
worker: Toast`,
			},
			wantFields: &MRFields{
				Branch:      "polecat/Toast/gt-abc",
				Target:      "integration/gt-epic",
				SourceIssue: "gt-abc",
				Worker:      "Toast",
			},
		},
		{
			name: "mixed with prose",
			issue: &Issue{
				Description: `branch: polecat/Capable/gt-def
target: main
source_issue: gt-def

This MR fixes a critical bug in the authentication system.
Please review carefully.

worker: Capable
rig: wasteland`,
			},
			wantFields: &MRFields{
				Branch:      "polecat/Capable/gt-def",
				Target:      "main",
				SourceIssue: "gt-def",
				Worker:      "Capable",
				Rig:         "wasteland",
			},
		},
		{
			name: "alternate key formats",
			issue: &Issue{
				Description: `branch: polecat/Max/gt-ghi
source-issue: gt-ghi
merge-commit: 789xyz`,
			},
			wantFields: &MRFields{
				Branch:      "polecat/Max/gt-ghi",
				SourceIssue: "gt-ghi",
				MergeCommit: "789xyz",
			},
		},
		{
			name: "case insensitive keys",
			issue: &Issue{
				Description: `Branch: polecat/Furiosa/gt-jkl
TARGET: main
Worker: Furiosa
RIG: gastown`,
			},
			wantFields: &MRFields{
				Branch: "polecat/Furiosa/gt-jkl",
				Target: "main",
				Worker: "Furiosa",
				Rig:    "gastown",
			},
		},
		{
			name: "extra whitespace",
			issue: &Issue{
				Description: `  branch:   polecat/Nux/gt-mno
target:main
  worker:   Nux  `,
			},
			wantFields: &MRFields{
				Branch: "polecat/Nux/gt-mno",
				Target: "main",
				Worker: "Nux",
			},
		},
		{
			name: "ignores empty values",
			issue: &Issue{
				Description: `branch: polecat/Nux/gt-pqr
target:
source_issue: gt-pqr`,
			},
			wantFields: &MRFields{
				Branch:      "polecat/Nux/gt-pqr",
				SourceIssue: "gt-pqr",
			},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			fields := ParseMRFields(tt.issue)

			if tt.wantNil {
				if fields != nil {
					t.Errorf("ParseMRFields() = %+v, want nil", fields)
				}
				return
			}

			if fields == nil {
				t.Fatal("ParseMRFields() = nil, want non-nil")
			}

			if fields.Branch != tt.wantFields.Branch {
				t.Errorf("Branch = %q, want %q", fields.Branch, tt.wantFields.Branch)
			}
			if fields.Target != tt.wantFields.Target {
				t.Errorf("Target = %q, want %q", fields.Target, tt.wantFields.Target)
			}
			if fields.SourceIssue != tt.wantFields.SourceIssue {
				t.Errorf("SourceIssue = %q, want %q", fields.SourceIssue, tt.wantFields.SourceIssue)
			}
			if fields.Worker != tt.wantFields.Worker {
				t.Errorf("Worker = %q, want %q", fields.Worker, tt.wantFields.Worker)
			}
			if fields.Rig != tt.wantFields.Rig {
				t.Errorf("Rig = %q, want %q", fields.Rig, tt.wantFields.Rig)
			}
			if fields.MergeCommit != tt.wantFields.MergeCommit {
				t.Errorf("MergeCommit = %q, want %q", fields.MergeCommit, tt.wantFields.MergeCommit)
			}
			if fields.CloseReason != tt.wantFields.CloseReason {
				t.Errorf("CloseReason = %q, want %q", fields.CloseReason, tt.wantFields.CloseReason)
			}
		})
	}
}

// TestFormatMRFields tests formatting MR fields to string.
func TestFormatMRFields(t *testing.T) {
	tests := []struct {
		name   string
		fields *MRFields
		want   string
	}{
		{
			name:   "nil fields",
			fields: nil,
			want:   "",
		},
		{
			name:   "empty fields",
			fields: &MRFields{},
			want:   "",
		},
		{
			name: "all fields",
			fields: &MRFields{
				Branch:      "polecat/Nux/gt-xyz",
				Target:      "main",
				SourceIssue: "gt-xyz",
				Worker:      "Nux",
				Rig:         "gastown",
				MergeCommit: "abc123def",
				CloseReason: "merged",
			},
			want: `branch: polecat/Nux/gt-xyz
target: main
source_issue: gt-xyz
worker: Nux
rig: gastown
merge_commit: abc123def
close_reason: merged`,
		},
		{
			name: "partial fields",
			fields: &MRFields{
				Branch:      "polecat/Toast/gt-abc",
				Target:      "main",
				SourceIssue: "gt-abc",
				Worker:      "Toast",
			},
			want: `branch: polecat/Toast/gt-abc
target: main
source_issue: gt-abc
worker: Toast`,
		},
		{
			name: "only close fields",
			fields: &MRFields{
				MergeCommit: "deadbeef",
				CloseReason: "rejected",
			},
			want: `merge_commit: deadbeef
close_reason: rejected`,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := FormatMRFields(tt.fields)
			if got != tt.want {
				t.Errorf("FormatMRFields() =\n%q\nwant\n%q", got, tt.want)
			}
		})
	}
}

// TestSetMRFields tests updating issue descriptions with MR fields.
func TestSetMRFields(t *testing.T) {
	tests := []struct {
		name   string
		issue  *Issue
		fields *MRFields
		want   string
	}{
		{
			name:  "nil issue",
			issue: nil,
			fields: &MRFields{
				Branch: "polecat/Nux/gt-xyz",
				Target: "main",
			},
			want: `branch: polecat/Nux/gt-xyz
target: main`,
		},
		{
			name:  "empty description",
			issue: &Issue{Description: ""},
			fields: &MRFields{
				Branch:      "polecat/Nux/gt-xyz",
				Target:      "main",
				SourceIssue: "gt-xyz",
			},
			want: `branch: polecat/Nux/gt-xyz
target: main
source_issue: gt-xyz`,
		},
		{
			name:  "preserve prose content",
			issue: &Issue{Description: "This is a description of the work.\n\nIt spans multiple lines."},
			fields: &MRFields{
				Branch: "polecat/Toast/gt-abc",
				Worker: "Toast",
			},
			want: `branch: polecat/Toast/gt-abc
worker: Toast

This is a description of the work.

It spans multiple lines.`,
		},
		{
			name: "replace existing fields",
			issue: &Issue{
				Description: `branch: polecat/Nux/gt-old
target: develop
source_issue: gt-old
worker: Nux

Some existing prose content.`,
			},
			fields: &MRFields{
				Branch:      "polecat/Nux/gt-new",
				Target:      "main",
				SourceIssue: "gt-new",
				Worker:      "Nux",
				MergeCommit: "abc123",
			},
			want: `branch: polecat/Nux/gt-new
target: main
source_issue: gt-new
worker: Nux
merge_commit: abc123

Some existing prose content.`,
		},
		{
			name: "preserve non-MR key-value lines",
			issue: &Issue{
				Description: `branch: polecat/Capable/gt-def
custom_field: some value
author: someone
target: main`,
			},
			fields: &MRFields{
				Branch:     "polecat/Capable/gt-ghi",
				Target:     "integration/epic",
				CloseReason: "merged",
			},
			want: `branch: polecat/Capable/gt-ghi
target: integration/epic
close_reason: merged

custom_field: some value
author: someone`,
		},
		{
			name:   "empty fields clears MR data",
			issue:  &Issue{Description: "branch: old\ntarget: old\n\nKeep this text."},
			fields: &MRFields{},
			want:   "Keep this text.",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			got := SetMRFields(tt.issue, tt.fields)
			if got != tt.want {
				t.Errorf("SetMRFields() =\n%q\nwant\n%q", got, tt.want)
			}
		})
	}
}

// TestMRFieldsRoundTrip tests that parse/format round-trips correctly.
func TestMRFieldsRoundTrip(t *testing.T) {
	original := &MRFields{
		Branch:      "polecat/Nux/gt-xyz",
		Target:      "main",
		SourceIssue: "gt-xyz",
		Worker:      "Nux",
		Rig:         "gastown",
		MergeCommit: "abc123def789",
		CloseReason: "merged",
	}

	// Format to string
	formatted := FormatMRFields(original)

	// Parse back
	issue := &Issue{Description: formatted}
	parsed := ParseMRFields(issue)

	if parsed == nil {
		t.Fatal("round-trip parse returned nil")
	}

	if *parsed != *original {
		t.Errorf("round-trip mismatch:\ngot  %+v\nwant %+v", parsed, original)
	}
}

// TestParseMRFieldsFromDesignDoc tests the example from the design doc.
func TestParseMRFieldsFromDesignDoc(t *testing.T) {
	// Example from docs/merge-queue-design.md
	description := `branch: polecat/Nux/gt-xyz
target: main
source_issue: gt-xyz
worker: Nux
rig: gastown`

	issue := &Issue{Description: description}
	fields := ParseMRFields(issue)

	if fields == nil {
		t.Fatal("ParseMRFields returned nil for design doc example")
	}

	// Verify all fields match the design doc
	if fields.Branch != "polecat/Nux/gt-xyz" {
		t.Errorf("Branch = %q, want polecat/Nux/gt-xyz", fields.Branch)
	}
	if fields.Target != "main" {
		t.Errorf("Target = %q, want main", fields.Target)
	}
	if fields.SourceIssue != "gt-xyz" {
		t.Errorf("SourceIssue = %q, want gt-xyz", fields.SourceIssue)
	}
	if fields.Worker != "Nux" {
		t.Errorf("Worker = %q, want Nux", fields.Worker)
	}
	if fields.Rig != "gastown" {
		t.Errorf("Rig = %q, want gastown", fields.Rig)
	}
}

// TestSetMRFieldsPreservesURL tests that URLs in prose are preserved.
func TestSetMRFieldsPreservesURL(t *testing.T) {
	// URLs contain colons which could be confused with key: value
	issue := &Issue{
		Description: `branch: old-branch
Check out https://example.com/path for more info.
Also see http://localhost:8080/api`,
	}

	fields := &MRFields{
		Branch: "new-branch",
		Target: "main",
	}

	result := SetMRFields(issue, fields)

	// URLs should be preserved
	if !strings.Contains(result, "https://example.com/path") {
		t.Error("HTTPS URL was not preserved")
	}
	if !strings.Contains(result, "http://localhost:8080/api") {
		t.Error("HTTP URL was not preserved")
	}
	if !strings.Contains(result, "branch: new-branch") {
		t.Error("branch field was not set")
	}
}