gml/internal/build/generate.go

/*
 *  GML - Go QML
 *  Copyright (c) 2019 Roland Singer [roland.singer@deserbit.com]
 *  Copyright (c) 2019 Sebastian Borchers [sebastian@deserbit.com]
 */

package build

import (
	"io/ioutil"
	"os"
	"path/filepath"
	"strings"
)

const (
	genGoFilename = "gml_gen.go"
)

// TODO: make concurrent with multiple goroutines.
func generate(ctx *Context) (err error) {
	gt, err := parseDirRecursive(ctx.SourceDir)
	if err != nil {
		return
	}

	err = generateCIncludeAllHeaderFile(gt, ctx.CGenIncludeDir)
	if err != nil {
		return
	}

	err = generateDummyFiles(ctx)
	if err != nil {
		return
	}

	for _, gp := range gt.Packages {
		err = generateGoFile(gp)
		if err != nil {
			return
		}

		err = generateCHeaderFile(gp, ctx.CGenDir)
		if err != nil {
			return
		}

		err = generateCPPHeaderFile(gp, ctx.CPPGenDir)
		if err != nil {
			return
		}

		err = generateCPPSourceFile(gp, ctx.CPPGenDir)
		if err != nil {
			return
		}
	}
	return
}

// TODO: only create dummies if the direcotories are empty.
// Create dummy files, because otherwise make fill fail if there are no sources files present.
// QMake is configured with a *.cpp & *.h
func generateDummyFiles(ctx *Context) (err error) {
	err = ioutil.WriteFile(filepath.Join(ctx.CGenDir, "_dummy.h"), []byte("// Dummy File"), 0755)
	if err != nil {
		return
	}

	err = ioutil.WriteFile(filepath.Join(ctx.CPPGenDir, "_dummy.h"), []byte("// Dummy File"), 0755)
	if err != nil {
		return
	}

	err = ioutil.WriteFile(filepath.Join(ctx.CPPGenDir, "_dummy.cpp"), []byte("// Dummy File"), 0755)
	return
}

// This shoult be in a separate directory, so no unnecessary files are in the global include dir.
func generateCIncludeAllHeaderFile(gt *genTargets, genDir string) (err error) {
	filename := filepath.Join(genDir, "gml_gen.h")

	// Create the file.
	f, err := os.Create(filename)
	if err != nil {
		return
	}
	defer func() {
		derr := f.Close()
		if derr != nil && err == nil {
			err = derr
		}
	}()

	f.WriteString("// This file is auto-generated by gml.\n")
	f.WriteString("#ifndef GML_GEN_C_INCLUDE_H\n")
	f.WriteString("#define GML_GEN_C_INCLUDE_H\n\n")

	for _, gp := range gt.Packages {
		f.WriteString("#include \"../" + gp.Name + ".h\"\n")
	}

	f.WriteString("\n#endif\n")
	return
}

func generateGoFile(gp *genPackage) (err error) {
	filename := filepath.Join(gp.Dir, genGoFilename)

	// Create the file.
	f, err := os.Create(filename)
	if err != nil {
		return
	}
	defer func() {
		derr := f.Close()
		if derr != nil && err == nil {
			err = derr
		}
	}()

	// Write the header.
	f.WriteString("// This file is auto-generated by gml.\n")
	f.WriteString("package " + gp.Name + "\n\n")
	f.WriteString("// #cgo pkg-config: Qt5Core Qt5Qml Qt5Quick\n")
	f.WriteString("// #cgo LDFLAGS: -lstdc++\n")
	f.WriteString("// #include <gml_gen.h>\n")
	f.WriteString("import \"C\"\n")
	f.WriteString("import (\n")
	f.WriteString("    \"unsafe\"\n")
	f.WriteString("    \"runtime\"\n")
	f.WriteString(")\n\n")

	for _, st := range gp.Structs {
		base := "gml_gen_" + st.Name

		// TODO: Error?
		// GMLInit().
		f.WriteString("func (_v *" + st.Name + ") GMLInit() {\n")
		f.WriteString("    _v.GMLObject_SetPointer(unsafe.Pointer(C." + base + "_new()))\n")
		f.WriteString("    runtime.SetFinalizer(_v, func(_v *" + st.Name + ") {\n")
		f.WriteString("        C." + base + "_free((C." + base + ")(_v.GMLObject_Pointer()))\n")
		f.WriteString("    })\n")
		f.WriteString("}\n\n")

		// Add all signals.
		for _, s := range st.Signals {
			f.WriteString("func (_v *" + st.Name + ") " + s.Name + "(")

			// Add the parameters.
			for i, p := range s.Params {
				if i != 0 {
					f.WriteString(", ")
				}
				f.WriteString(p.Name + " " + p.Type)
			}

			f.WriteString(") {\n")
			f.WriteString("    _ptr := (C." + base + ")(_v.GMLObject_Pointer())\n")
			f.WriteString("    C." + base + "_" + s.Name + "(_ptr)\n") // TODO: params + return type + error
			f.WriteString("}\n\n")
		}
	}

	return
}

// TODO: add package prefix!
func generateCHeaderFile(gp *genPackage, genDir string) (err error) {
	filename := filepath.Join(genDir, gp.Name+".h")

	// Create the file.
	f, err := os.Create(filename)
	if err != nil {
		return
	}
	defer func() {
		derr := f.Close()
		if derr != nil && err == nil {
			err = derr
		}
	}()

	// Write the header.
	f.WriteString("// This file is auto-generated by gml.\n")
	f.WriteString("#ifndef GML_GEN_C_" + strings.ToUpper(gp.Name) + "_H\n")
	f.WriteString("#define GML_GEN_C_" + strings.ToUpper(gp.Name) + "_H\n\n")
	f.WriteString("#ifdef __cplusplus\n")
	f.WriteString("extern \"C\" {\n")
	f.WriteString("#endif\n\n")

	for _, st := range gp.Structs {
		f.WriteString("//###\n")
		f.WriteString("//### " + st.Name + "\n")
		f.WriteString("//###\n\n")

		base := "gml_gen_" + st.Name
		f.WriteString("typedef void* " + base + ";\n\n")

		// Constructor & destructor.
		f.WriteString(base + " " + base + "_new();\n")
		f.WriteString("void " + base + "_free(" + base + ");\n\n")

		// Add all signals.
		if len(st.Signals) > 0 {
			for _, s := range st.Signals {
				f.WriteString("void " + base + "_" + s.Name + "(" + base + " _v") // TODO: return value.
				for _, p := range s.Params {
					f.WriteString(p.Type + " " + p.Name) // TODO: to C types.
				}
				f.WriteString(");\n")
			}
		}

		f.WriteString("\n")
	}

	f.WriteString("#ifdef __cplusplus\n")
	f.WriteString("}\n")
	f.WriteString("#endif\n\n")
	f.WriteString("#endif\n")
	return
}

// TODO: add package prefix!
func generateCPPSourceFile(gp *genPackage, genDir string) (err error) {
	filename := filepath.Join(genDir, gp.Name+".cpp")

	// Create the file.
	f, err := os.Create(filename)
	if err != nil {
		return
	}
	defer func() {
		derr := f.Close()
		if derr != nil && err == nil {
			err = derr
		}
	}()

	// Write the header.
	f.WriteString("// This file is auto-generated by gml.\n")
	f.WriteString("#include \"" + gp.Name + ".h\"\n\n")

	for _, st := range gp.Structs {
		f.WriteString("//###\n")
		f.WriteString("//### " + st.Name + "\n")
		f.WriteString("//###\n\n")

		base := "gml_gen_" + st.Name
		cppbase := "GMLGen" + st.Name

		// Constructor. TODO: try catch
		f.WriteString(base + " " + base + "_new() {\n")
		f.WriteString("    auto _vv = new " + cppbase + "();\n")
		f.WriteString("    return (void*)_vv;\n")
		f.WriteString("}\n\n")

		// Destructor. TODO: try catch
		f.WriteString("void " + base + "_free(" + base + " _v) {\n")
		f.WriteString("    if (_v == NULL) return;\n")
		f.WriteString("    auto _vv = (" + cppbase + "*)_v;\n")
		f.WriteString("    delete _vv;\n")
		f.WriteString("    _v = NULL;\n")
		f.WriteString("}\n\n")

		// Add all signals.
		if len(st.Signals) > 0 {
			for _, s := range st.Signals {
				f.WriteString("void " + base + "_" + s.Name + "(" + base + " _v") // TODO: return value.
				for _, p := range s.Params {
					f.WriteString(p.Type + " " + p.Name) // TODO: to C types.
				}
				f.WriteString(") {\n")
				f.WriteString("    auto _vv = (" + cppbase + "*)_v;\n")
				f.WriteString("    emit _vv->" + s.Name + "();\n") // TODO: params
				f.WriteString("}\n")
			}
		}
		f.WriteString("\n")
	}
	return
}

// TODO: add package prefix!
func generateCPPHeaderFile(gp *genPackage, genDir string) (err error) {
	filename := filepath.Join(genDir, gp.Name+".h")

	// Create the file.
	f, err := os.Create(filename)
	if err != nil {
		return
	}
	defer func() {
		derr := f.Close()
		if derr != nil && err == nil {
			err = derr
		}
	}()

	// Write the header.
	f.WriteString("// This file is auto-generated by gml.\n")
	f.WriteString("#ifndef GML_GEN_CPP_" + strings.ToUpper(gp.Name) + "_H\n")
	f.WriteString("#define GML_GEN_CPP_" + strings.ToUpper(gp.Name) + "_H\n\n")
	f.WriteString("#include \"../gen_c/" + gp.Name + ".h\"\n")
	f.WriteString("#include <QObject>\n\n")

	for _, st := range gp.Structs {
		f.WriteString("//###\n")
		f.WriteString("//### " + st.Name + "\n")
		f.WriteString("//###\n\n")

		f.WriteString("class GMLGen" + st.Name + " : public QObject\n")
		f.WriteString("{\n")
		f.WriteString("    Q_OBJECT\n")

		// Add all signals.
		if len(st.Signals) > 0 {
			f.WriteString("signals:\n")
			for _, s := range st.Signals {
				f.WriteString("    void " + s.Name + "(") // TODO: return value.
				for i, p := range s.Params {
					if i != 0 {
						f.WriteString(", ")
					}
					f.WriteString(p.Type + " " + p.Name) // TODO: to C++ types.
				}
				f.WriteString(");\n")
			}
		}

		f.WriteString("};\n\n")
	}

	f.WriteString("#endif\n")
	return
}