package cursor

import (
	"database/sql"
	"encoding/json"
	"os"
	"path/filepath"
	"testing"

	_ "modernc.org/sqlite"
)

func TestProjectPathFromURI(t *testing.T) {
	cases := []struct {
		name string
		uri  string
		want string
	}{
		{"windows 盘符", "file:///d:/Project/x", "d:/Project/x"},
		{"编码盘符", "file:///d%3A/Project/x", "d:/Project/x"},
		{"带空格编码", "file:///d:/My%20Projects/x", "d:/My Projects/x"},
		{"posix 路径", "file:///home/user/x", "/home/user/x"},
		{"非 file URI", "vscode-remote://ssh-remote/home/x", ""},
		{"普通路径", "d:/Project/x", ""},
		{"空串", "", ""},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			if got := projectPathFromURI(tc.uri); got != tc.want {
				t.Fatalf("projectPathFromURI(%q) = %q, want %q", tc.uri, got, tc.want)
			}
		})
	}
}

// createStateDB 在 userDir/globalStorage 下创建含最近打开列表的 state.vscdb。
func createStateDB(t *testing.T, userDir string, uris []string) {
	t.Helper()
	if err := os.MkdirAll(filepath.Join(userDir, "globalStorage"), 0o755); err != nil {
		t.Fatal(err)
	}
	db, err := sql.Open("sqlite", filepath.Join(userDir, "globalStorage", "state.vscdb"))
	if err != nil {
		t.Fatal(err)
	}
	defer db.Close()
	if _, err := db.Exec("CREATE TABLE ItemTable (key TEXT UNIQUE, value TEXT)"); err != nil {
		t.Fatal(err)
	}
	entries := make([]map[string]string, 0, len(uris))
	for _, uri := range uris {
		entries = append(entries, map[string]string{"folderUri": uri})
	}
	raw, _ := json.Marshal(map[string]any{"entries": entries})
	if _, err := db.Exec(
		"INSERT INTO ItemTable (key, value) VALUES ('history.recentlyOpenedPathsList', ?)", string(raw),
	); err != nil {
		t.Fatal(err)
	}
}

func readRecentlyOpened(t *testing.T, userDir string) []string {
	t.Helper()
	db, err := sql.Open("sqlite", filepath.Join(userDir, "globalStorage", "state.vscdb"))
	if err != nil {
		t.Fatal(err)
	}
	defer db.Close()
	var raw string
	if err := db.QueryRow(
		"SELECT value FROM ItemTable WHERE key = 'history.recentlyOpenedPathsList'",
	).Scan(&raw); err != nil {
		t.Fatal(err)
	}
	var payload struct {
		Entries []struct {
			FolderURI string `json:"folderUri"`
		} `json:"entries"`
	}
	if err := json.Unmarshal([]byte(raw), &payload); err != nil {
		t.Fatal(err)
	}
	result := make([]string, 0, len(payload.Entries))
	for _, item := range payload.Entries {
		result = append(result, item.FolderURI)
	}
	return result
}

func TestRemoveRecentlyOpenedEntry(t *testing.T) {
	t.Run("命中条目被移除", func(t *testing.T) {
		userDir := t.TempDir()
		createStateDB(t, userDir, []string{"file:///d:/Proj/A", "file:///d:/Proj/B"})
		removed, err := removeRecentlyOpenedEntry(userDir, "d:/Proj/A")
		if err != nil {
			t.Fatal(err)
		}
		if removed != 1 {
			t.Fatalf("removed = %d, want 1", removed)
		}
		remaining := readRecentlyOpened(t, userDir)
		if len(remaining) != 1 || remaining[0] != "file:///d:/Proj/B" {
			t.Fatalf("remaining = %v, want [file:///d:/Proj/B]", remaining)
		}
	})

	t.Run("未命中不写库", func(t *testing.T) {
		userDir := t.TempDir()
		createStateDB(t, userDir, []string{"file:///d:/Proj/A"})
		removed, err := removeRecentlyOpenedEntry(userDir, "d:/Proj/Other")
		if err != nil {
			t.Fatal(err)
		}
		if removed != 0 {
			t.Fatalf("removed = %d, want 0", removed)
		}
		if got := readRecentlyOpened(t, userDir); len(got) != 1 {
			t.Fatalf("remaining = %v, want 1 entry", got)
		}
	})

	t.Run("缺失数据库返回零值无错误", func(t *testing.T) {
		removed, err := removeRecentlyOpenedEntry(t.TempDir(), "d:/Proj/A")
		if err != nil {
			t.Fatalf("unexpected error: %v", err)
		}
		if removed != 0 {
			t.Fatalf("removed = %d, want 0", removed)
		}
	})

	t.Run("损坏数据库返回错误", func(t *testing.T) {
		userDir := t.TempDir()
		if err := os.MkdirAll(filepath.Join(userDir, "globalStorage"), 0o755); err != nil {
			t.Fatal(err)
		}
		if err := os.WriteFile(
			filepath.Join(userDir, "globalStorage", "state.vscdb"), []byte("not a db"), 0o644,
		); err != nil {
			t.Fatal(err)
		}
		if _, err := removeRecentlyOpenedEntry(userDir, "d:/Proj/A"); err == nil {
			t.Fatal("want error for corrupt db, got nil")
		}
	})
}

func TestRemoveWorkspaceStorageEntries(t *testing.T) {
	t.Run("命中目录被整目录删除", func(t *testing.T) {
		userDir := t.TempDir()
		target := filepath.Join(userDir, "workspaceStorage", "hash-a")
		other := filepath.Join(userDir, "workspaceStorage", "hash-b")
		for dir, folder := range map[string]string{
			target: "file:///d:/Proj/A",
			other:  "file:///d:/Proj/B",
		} {
			if err := os.MkdirAll(dir, 0o755); err != nil {
				t.Fatal(err)
			}
			raw, _ := json.Marshal(map[string]string{"folder": folder})
			if err := os.WriteFile(filepath.Join(dir, "workspace.json"), raw, 0o644); err != nil {
				t.Fatal(err)
			}
		}
		removed, err := removeWorkspaceStorageEntries(userDir, "d:/Proj/A")
		if err != nil {
			t.Fatal(err)
		}
		if removed != 1 {
			t.Fatalf("removed = %d, want 1", removed)
		}
		if _, err := os.Stat(target); !os.IsNotExist(err) {
			t.Fatalf("target dir should be removed, stat err = %v", err)
		}
		if _, err := os.Stat(other); err != nil {
			t.Fatalf("other dir should remain: %v", err)
		}
	})

	t.Run("缺失 workspaceStorage 返回零值无错误", func(t *testing.T) {
		removed, err := removeWorkspaceStorageEntries(t.TempDir(), "d:/Proj/A")
		if err != nil {
			t.Fatalf("unexpected error: %v", err)
		}
		if removed != 0 {
			t.Fatalf("removed = %d, want 0", removed)
		}
	})
}