Migrate to go

[ppvan]

In the end, I can't deal with fixing endless meson bug and binding C library. This issue list benefits and changes when migrate to Go:

Benefit:

• Much better ecosystem with a good standard library, no need for csv or json-glib, they are in go std by default
• Strong library to work with postgresql, native Go binding with SQL types...
• Better language tooling, dev expriences
• More reliable complier (I spent countless hours on meson and vala shit)

Challeges

• Gtk support not strong as Vala (Resource files, translations, icons files, metainfo files, how to embeded app config, blueprint compiler, binding events...)
• Custom widgets? (psequel custom ListView and friends alot, they may not work)
• Build flatpak with golang and gtk

Work to do:

• [ ] Build a simple hello world with gotk4, but with all gtk things (blueprints, metainfo, flatpak)
• [ ] Bind go function with gtk signal. Implement component communications
• [ ] Migrate connection view
• [ ] Migrate schema view
• [ ] Migrate query view
• [ ] Consider remove data view
• [ ] Migrate backup and restore features

[ppvan]

Infomation schema implementation:

type InformationSchema struct {
    metadata.LoggingReader
    pf                  func(int) string
    hasFunctions        bool
    hasSequences        bool
    hasIndexes          bool
    hasConstraints      bool
    hasCheckConstraints bool
    hasTablePrivileges  bool
    hasColumnPrivileges bool
    hasUsagePrivileges  bool
    clauses             map[ClauseName]string
    limit               int
    systemSchemas       []string
    currentSchema       string
    dataTypeFormatter   func(metadata.Column) string
}

type Column struct {
    Catalog         string
    Schema          string
    Table           string
    Name            string
    OrdinalPosition int
    DataType        string
    // ScanType        reflect.Type
    Default         string
    ColumnSize      int
    DecimalDigits   int
    NumPrecRadix    int
    CharOctetLength int
    IsNullable      Bool
}

type Table struct {
    Catalog string
    Schema  string
    Name    string
    Type    string
    Rows    int64
    Size    string
    Comment string
}

type Constraint struct {
    Catalog string
    Schema  string
    Table   string
    Name    string
    Type    string

    IsDeferrable        Bool
    IsInitiallyDeferred Bool

    ForeignCatalog string
    ForeignSchema  string
    ForeignTable   string
    ForeignName    string
    MatchType      string
    UpdateRule     string
    DeleteRule     string

    CheckClause string
}