package dbstore

import (
  "compress/gzip"
  "context"
  db_sql "database/sql"
  "encoding/xml"
  "embed"
  "errors"
  "fmt"
  _ "github.com/mattn/go-sqlite3"
  "github.com/pablotron/cvez/cpedict"
  io_fs "io/fs"
  "os"
  "reflect"
  "testing"
  "time"
)

func getTestDictionary(path string) (cpedict.Dictionary, error) {
  var dict cpedict.Dictionary

  // open test data
  f, err := os.Open(path)
  if err != nil {
    return dict, err
  }
  defer f.Close()

  // create zip reader
  gz, err := gzip.NewReader(f)
  if err != nil {
    return dict, err
  }
  defer gz.Close()

  // create xml decoder
  d := xml.NewDecoder(gz)

  // decode xml
  if err = d.Decode(&dict); err != nil {
    return dict, err
  }

  // return success
  return dict, nil
}
//go:embed testdata/sql/*.sql
var testSqlFs embed.FS

var testSqlIds = map[string]bool {
  "init": false,
  "insert-cpe": true,
  "insert-title": true,
  "insert-ref": true,
}

func getTestQueries() (map[string]string, error) {
  r := make(map[string]string)

  for id, _ := range(testSqlIds) {
    path := fmt.Sprintf("testdata/sql/%s.sql", id)
    if data, err := testSqlFs.ReadFile(path); err != nil {
      return r, err
    } else {
      r[id] = string(data)
    }
  }

  return r, nil
}

func ignoreTestSimple(t *testing.T) {
  testDbPath := "./testdata/foo.db"
  // get queries
  queries, err := getTestQueries()
  if err != nil {
    t.Error(err)
    return
  }

  // load test CPEs
  dict, err := getTestDictionary("testdata/test-0.xml.gz")
  if err != nil {
    t.Error(err)
    return
  }

  // does test db exist?
  if _, err = os.Stat(testDbPath); err != nil {
    if !errors.Is(err, io_fs.ErrNotExist) {
      t.Error(err)
      return
    }
  } else if err == nil {
    // remove test db
    if err = os.Remove(testDbPath); err != nil {
      t.Error(err)
      return
    }
  }

  // init db
  db, err := db_sql.Open("sqlite3", testDbPath)
  if err != nil {
    t.Error(err)
    return
  }
  defer db.Close()

  // init tables
  if _, err := db.Exec(queries["init"]); err != nil {
    t.Error(err)
    return
  }

  tx, err := db.Begin()
  if err != nil {
    t.Error(err)
    return
  }

  // build statements
  sts := make(map[string]*db_sql.Stmt)
  for id, use := range(testSqlIds) {
    if use {
      if st, err := tx.Prepare(queries[id]); err != nil {
        t.Error(err)
        return
      } else {
        sts[id] = st
        defer sts[id].Close()
      }
    }
  }

  // add items
  for _, item := range(dict.Items) {
    // add cpe
    rs, err := sts["insert-cpe"].Exec(item.CpeUri, item.Cpe23Item.Name);
    if err != nil {
      t.Error(err)
      return
    }

    // get last row ID
    id, err := rs.LastInsertId()
    if err != nil {
      t.Error(err)
      return
    }

    // add titles
    for _, title := range(item.Titles) {
      if _, err := sts["insert-title"].Exec(id, title.Lang, title.Text); err != nil {
        t.Error(err)
        return
      }
    }

    // add refs
    for _, ref := range(item.References) {
      if _, err := sts["insert-ref"].Exec(id, ref.Href, ref.Text); err != nil {
        t.Error(err)
        return
      }
    }
  }

  // commit changes
  if err = tx.Commit(); err != nil {
    t.Error(err)
    return
  }
}

func createTestDb(ctx context.Context, path string) (DbStore, error) {
  // remove existing file
  err := os.Remove(path)
  if err != nil && !errors.Is(err, io_fs.ErrNotExist) {
    return DbStore{}, err
  }

  // open db
  return Open(path)
}

func seedTestDb(ctx context.Context, db DbStore) error {
  // load test CPEs
  dict, err := getTestDictionary("testdata/test-0.xml.gz")
  if err != nil {
    return err
  }

  // add cpe dictionary
  return db.AddCpeDictionary(ctx, dict)

  // TODO: seed with other data
}

func TestOpen(t *testing.T) {
  tests := []struct {
    name string
    path string
    exp bool
  } {
    { "pass", "./testdata/test-open.db", true },
    // { "fail", "file://invalid/foobar", false },
  }

  for _, test := range(tests) {
    t.Run(test.name, func(t *testing.T) {
      got, err := Open(test.path)
      if test.exp && err != nil {
        t.Error(err)
      } else if !test.exp && err == nil {
        t.Errorf("got %v, exp error", got)
      }
    })
  }
}

func TestInitFail(t *testing.T) {
  // set deadline to 2 hours ago
  deadline := time.Now().Add(-2 * time.Hour)
  ctx, _ := context.WithDeadline(context.Background(), deadline)

  db, err := createTestDb(ctx, "./testdata/test-init-fail.db")
  if err != nil {
    t.Errorf("createTestDb(): got %v, exp error", db)
  }

  if err = db.Init(ctx); err == nil {
    t.Errorf("Init(): got %v, exp error", db)
  }
}

func TestGetQuery(t *testing.T) {
  tests := []struct {
    name string
    val string
    exp bool
  } {
    { "pass", "init", true },
    { "fail", "invalid", false },
  }

  for _, test := range(tests) {
    t.Run(test.name, func(t *testing.T) {
      got, err := getQuery(test.val)
      if err != nil && test.exp {
        t.Error(err)
      } else if err == nil && !test.exp {
        t.Errorf("got %v, exp error", got)
      }
    })
  }
}

func TestGetQueries(t *testing.T) {
  tests := []struct {
    name string
    vals []string
    exp bool
  } {
    { "pass", []string { "init" }, true },
    { "fail", []string { "invalid" }, false },
  }

  for _, test := range(tests) {
    t.Run(test.name, func(t *testing.T) {
      got, err := getQueries(test.vals)
      if err != nil && test.exp {
        t.Error(err)
      } else if err == nil && !test.exp {
        t.Errorf("got %v, exp error", got)
      }
    })
  }
}

func TestAddCpeDictionaryPass(t *testing.T) {
  path := "./testdata/test-addcpedict.db"
  ctx := context.Background()

  // create db
  db, err := createTestDb(ctx, path)
  if err != nil {
    t.Error(err)
    return
  }

  // load test CPEs
  dict, err := getTestDictionary("testdata/test-0.xml.gz")
  if err != nil {
    t.Error(err)
    return
  }

  // add cpe dictionary
  if err := db.AddCpeDictionary(ctx, dict); err != nil {
    t.Error(err)
    return
  }
}

func TestAddCpeDictionaryFail(t *testing.T) {
  // load test CPEs
  dict, err := getTestDictionary("testdata/test-0.xml.gz")
  if err != nil {
    t.Error(err)
    return
  }

  funcTests := []struct {
    name string
    fn func(string) func(*testing.T)
  } {{
    name: "deadline",
    fn: func(path string) func(*testing.T) {
      return func(t *testing.T) {
        deadline := time.Now().Add(-2 * time.Hour)
        ctx, _ := context.WithDeadline(context.Background(), deadline)

        // create db
        db, err := createTestDb(ctx, path)
        if err != nil {
          t.Error(err)
          return
        }

        // add cpe dictionary
        if err := db.AddCpeDictionary(ctx, dict); err == nil {
          t.Errorf("got success, exp error")
        }
      }
    },
  }, {
    name: "tx",
    fn: func(path string) func(*testing.T) {
      return func(t *testing.T) {
        ctx := context.Background()

        // create db
        db, err := createTestDb(ctx, path)
        if err != nil {
          t.Error(err)
          return
        }

        // begin transaction
        if _, err = db.db.BeginTx(ctx, nil); err != nil {
          t.Error(err)
          return
        }

// FIXME: busted
//         // add cpe dictionary
//         if err := db.AddCpeDictionary(ctx, dict); err == nil {
//           t.Errorf("got success, exp error")
//         }
      }
    },
  }}

  for _, test := range(funcTests) {
    path := fmt.Sprintf("./testdata/test-addcpedict-fail-%s.db", test.name)
    t.Run(test.name, test.fn(path))
  }

  dictTests := []struct {
    name string
    dict cpedict.Dictionary
  } {{
    name: "bad-cpe23",
    dict: cpedict.Dictionary {
      Items: []cpedict.Item { cpedict.Item{} },
    },
  }, {
    name: "bad-title",
    dict: cpedict.Dictionary {
      Items: []cpedict.Item {
        cpedict.Item {
          CpeUri: "cpe:/a",

          Cpe23Item: cpedict.Cpe23Item {
            Name: "cpe:2.3:*:*:*:*:*:*:*:*:*:*:*",
          },

          Titles: []cpedict.Title {
            cpedict.Title {},
          },
        },
      },
    },
  }, {
    name: "bad-ref",
    dict: cpedict.Dictionary {
      Items: []cpedict.Item {
        cpedict.Item {
          CpeUri: "cpe:/a",

          Cpe23Item: cpedict.Cpe23Item {
            Name: "cpe:2.3:*:*:*:*:*:*:*:*:*:*:*",
          },

          Titles: []cpedict.Title {
            cpedict.Title { Lang: "en-US", Text: "foo" },
          },

          References: []cpedict.Reference {
            cpedict.Reference {},
          },
        },
      },
    },
  }}

  for _, test := range(dictTests) {
    t.Run(test.name, func(t *testing.T) {
      ctx := context.Background()
      path := fmt.Sprintf("./testdata/test-addcpedict-fail-%s.db", test.name)

      // create db
      db, err := createTestDb(ctx, path)
      if err != nil {
        t.Error(err)
        return
      }

      // add cpe dictionary
      if err := db.AddCpeDictionary(ctx, test.dict); err == nil {
        t.Errorf("got success, exp error")
      }
    })
  }
}

func TestCpeSearch(t *testing.T) {
  path := "./testdata/test-search.db"
  ctx := context.Background()

  // tests that are expected to pass
  passTests := []struct {
    t CpeSearchType // search type
    q string // query string
    exp []string // expected search results (cpe23s)
  } {{
    t: CpeSearchAll,
    q: "advisory AND book",
    exp: []string {
      "cpe:2.3:a:\\$0.99_kindle_books_project:\\$0.99_kindle_books:6:*:*:*:*:android:*:*",
    },
  }, {
    t: CpeSearchTitle,
    q: "project",
    exp: []string {
      "cpe:2.3:a:\\@thi.ng\\/egf_project:\\@thi.ng\\/egf:-:*:*:*:*:node.js:*:*",
      "cpe:2.3:a:\\@thi.ng\\/egf_project:\\@thi.ng\\/egf:0.1.0:*:*:*:*:node.js:*:*",
      "cpe:2.3:a:\\@thi.ng\\/egf_project:\\@thi.ng\\/egf:0.2.0:*:*:*:*:node.js:*:*",
      "cpe:2.3:a:\\@thi.ng\\/egf_project:\\@thi.ng\\/egf:0.2.1:*:*:*:*:node.js:*:*",
      "cpe:2.3:a:\\$0.99_kindle_books_project:\\$0.99_kindle_books:6:*:*:*:*:android:*:*",
    },
  }, {
    t: CpeSearchRef,
    q: "advisory",
    exp: []string {
      "cpe:2.3:a:\\@thi.ng\\/egf_project:\\@thi.ng\\/egf:-:*:*:*:*:node.js:*:*",
      "cpe:2.3:a:\\@thi.ng\\/egf_project:\\@thi.ng\\/egf:0.1.0:*:*:*:*:node.js:*:*",
      "cpe:2.3:a:\\@thi.ng\\/egf_project:\\@thi.ng\\/egf:0.2.0:*:*:*:*:node.js:*:*",
      "cpe:2.3:a:\\@thi.ng\\/egf_project:\\@thi.ng\\/egf:0.2.1:*:*:*:*:node.js:*:*",
      "cpe:2.3:a:360totalsecurity:360_total_security:12.1.0.1005:*:*:*:*:*:*:*",
      "cpe:2.3:a:\\$0.99_kindle_books_project:\\$0.99_kindle_books:6:*:*:*:*:android:*:*",
    },
  }}

  // create db
  db, err := createTestDb(ctx, path)
  if err != nil {
    t.Error(err)
    return
  }

  // seed test database
  if err = seedTestDb(ctx, db); err != nil {
    t.Error(err)
    return
  }

  for _, test := range(passTests) {
    t.Run(test.t.String(), func(t *testing.T) {
      rows, err := db.CpeSearch(ctx, test.t, test.q)
      if err != nil {
        t.Error(err)
        return
      }

      // build ids
      got := make([]string, len(rows))
      for i, row := range(rows) {
        got[i] = row.Cpe23
      }

      if !reflect.DeepEqual(got, test.exp) {
        t.Errorf("got \"%v\", exp \"%v\"", got, test.exp)
        return
      }
    })
  }

  // tests that are expected to fail
  failTests := []struct {
    name string // test name
    t CpeSearchType // search type
    q string // query string
  } {
    { "bad-search-type", CpeSearchType(255), "" },
  }

  for _, test := range(failTests) {
    t.Run(test.name, func(t *testing.T) {
      if got, err := db.CpeSearch(ctx, test.t, test.q); err == nil {
        t.Errorf("got \"%v\", exp error", got)
      }
    })
  }
}