/**
Copyright: Copyright (c) 2016-2017, Joakim Brännström. All rights reserved.
License: MPL-2
Author: Joakim Brännström (joakim.brannstrom@gmx.com)

This Source Code Form is subject to the terms of the Mozilla Public License,
v.2.0. If a copy of the MPL was not distributed with this file, You can obtain
one at http://mozilla.org/MPL/2.0/.

Generate PlantUML diagrams of C/C++ source code.
*/
module dextool.plugin.frontend.plantuml;

import std.typecons : Flag, Yes, No, Tuple;
import logger = std.experimental.logger;

import dextool.compilation_db;
import dextool.type;

import dextool.plugin.backend.plantuml : Controller, Parameters, Products;
import cpptooling.data : CppRoot, CppNamespace, CppClass;

struct RawConfiguration {
    string[] cflags;
    string[] compileDb;
    string[] fileExclude;
    string[] fileInclude;
    string[] inFiles;
    string componentStrip;
    string filePrefix = "view_";
    string out_;
    bool classInheritDep;
    bool classMemberDep;
    bool classMethod;
    bool classParamDep;
    bool componentByFile;
    bool generateDot;
    bool generateStyleInclude;
    bool help;
    bool shortPluginHelp;
    bool skipFileError;

    string[] originalFlags;

    void parse(string[] args) {
        import std.getopt;

        originalFlags = args.dup;

        // dfmt off
        try {
            getopt(args, std.getopt.config.keepEndOfOptions, "h|help", &help,
                   "class-method", &classMethod,
                   "class-paramdep", &classParamDep,
                   "class-inheritdep", &classInheritDep,
                   "class-memberdep", &classMemberDep,
                   "compile-db", &compileDb,
                   "comp-by-file", &componentByFile,
                   "comp-strip", &componentStrip,
                   "file-exclude", &fileExclude,
                   "file-prefix", &filePrefix,
                   "file-include", &fileInclude,
                   "gen-dot", &generateDot,
                   "gen-style-incl", &generateStyleInclude,
                   "in", &inFiles,
                   "out", &out_,
                   "short-plugin-help", &shortPluginHelp,
                   "skip-file-error", &skipFileError,
                   );
        }
        catch (std.getopt.GetOptException ex) {
            logger.error(ex.msg);
            help = true;
        }
        // dfmt on

        import std.algorithm : find;
        import std.array : array;
        import std.range : drop;

        // at this point args contain "what is left". What is interesting then is those after "--".
        cflags = args.find("--").drop(1).array();
    }

    void printHelp() {
        import std.stdio : writefln;

        writefln("%s\n\n%s\n%s", plantuml_opt.usage, plantuml_opt.optional, plantuml_opt.others);
    }

    void dump() {
        logger.trace(this);
    }
}

// dfmt off
static auto plantuml_opt = Tuple!(string, "usage", string, "optional", string, "others")(
    "usage:
 dextool uml [options] [--compile-db=...] [--file-exclude=...] [--in=...] [--] [CFLAGS...]
 dextool uml [options] [--compile-db=...] [--file-include=...] [--in=...] [--] [CFLAGS...]",
    // -------------
    " --out=dir           directory for generated files [default: ./]
 --file-prefix=p     Prefix used when generating test artifacts [default: view_]
 --class-method      Include methods in the generated class diagram
 --class-paramdep    Class method parameters as directed association in diagram
 --class-inheritdep  Class inheritance in diagram
 --class-memberdep   Class member as composition/aggregation in diagram
 --comp-by-file      Components by file instead of directory
 --comp-strip=r      Regex used to strip path used to derive component name
 --gen-style-incl    Generate a style file and include in all diagrams
 --gen-dot           Generate a dot graph block in the plantuml output
 --skip-file-error   Skip files that result in compile errors (only when using compile-db and processing all files)",
    // -------------
"others:
 --in=               Input files to parse
 --compile-db=j      Retrieve compilation parameters from the file
 --file-exclude=     Exclude files from generation matching the regex
 --file-include=     Include the scope of the test double to those files
                     matching the regex

REGEX
The regex syntax is found at http://dlang.org/phobos/std_regex.html

Information about --file-exclude.
  The regex must fully match the filename the AST node is located in.
  If it matches all data from the file is excluded from the generated code.

Information about --file-include.
  The regex must fully match the filename the AST node is located in.
  Only symbols from files matching the include affect the generated test double.
"
);
// dfmt on

/** Frontend for PlantUML generator.
 *
 * TODO implement --in=... for multi-file handling
 */
class PlantUMLFrontend : Controller, Parameters, Products {
    import std..string : toLower;
    import std.regex : regex, Regex;
    import std.typecons : Flag, Yes, No;
    import my.filter : ReFilter;
    import cpptooling.type : FilePrefix;
    import dextool.type : Path;

    import dsrcgen.plantuml;

    static struct FileData {
        import dextool.io : WriteStrategy;

        Path filename;
        string data;
        WriteStrategy strategy;
    }

    static const fileExt = ".pu";
    static const inclExt = ".iuml";

    // TODO ugly hack to remove immutable. Fix it appropriately
    Path[] input_files;
    immutable Path output_dir;
    immutable Path file_classes;
    immutable Path file_components;
    immutable Path file_style;
    immutable Path file_style_output;

    immutable FilePrefix file_prefix;

    immutable Flag!"genClassMethod" gen_class_method;
    immutable Flag!"genClassParamDependency" gen_class_param_dep;
    immutable Flag!"genClassInheritDependency" gen_class_inherit_dep;
    immutable Flag!"genClassMemberDependency" gen_class_member_dep;
    immutable Flag!"doStyleIncl" do_style_incl;
    immutable Flag!"doGenDot" do_gen_dot;
    immutable Flag!"doComponentByFile" do_comp_by_file;

    ReFilter fileFilter;
    Regex!char comp_strip;

    /// Data produced by the generator intended to be written to specified file.
    FileData[] fileData;

    static auto makeVariant(ref RawConfiguration parsed) {
        auto gen_class_method = cast(Flag!"genClassMethod") parsed.classMethod;
        auto gen_class_param_dep = cast(Flag!"genClassParamDependency") parsed.classParamDep;
        auto gen_class_inherit_dep = cast(Flag!"genClassInheritDependency") parsed.classInheritDep;
        auto gen_class_member_dep = cast(Flag!"genClassMemberDependency") parsed.classMemberDep;

        auto gen_style_incl = cast(Flag!"doStyleIncl") parsed.generateStyleInclude;
        auto gen_dot = cast(Flag!"doGenDot") parsed.generateDot;
        auto do_comp_by_file = cast(Flag!"doComponentByFile") parsed.componentByFile;

        auto variant = new PlantUMLFrontend(FilePrefix(parsed.filePrefix),
                Path(parsed.out_), gen_style_incl, gen_dot, gen_class_method,
                gen_class_param_dep, gen_class_inherit_dep, gen_class_member_dep, do_comp_by_file);

        variant.fileFilter = ReFilter(parsed.fileInclude, parsed.fileExclude);
        variant.comp_strip = () {
            if (parsed.componentStrip.length != 0)
                return regex(parsed.componentStrip);
            return Regex!char.init;
        }();

        return variant;
    }

    this(FilePrefix file_prefix, Path output_dir, Flag!"doStyleIncl" style_incl,
            Flag!"doGenDot" gen_dot, Flag!"genClassMethod" class_method,
            Flag!"genClassParamDependency" class_param_dep, Flag!"genClassInheritDependency" class_inherit_dep,
            Flag!"genClassMemberDependency" class_member_dep,
            Flag!"doComponentByFile" do_comp_by_file) {
        this.file_prefix = file_prefix;
        this.output_dir = output_dir;
        this.gen_class_method = class_method;
        this.gen_class_param_dep = class_param_dep;
        this.gen_class_inherit_dep = class_inherit_dep;
        this.gen_class_member_dep = class_member_dep;
        this.do_comp_by_file = do_comp_by_file;
        this.do_gen_dot = gen_dot;
        this.do_style_incl = style_incl;

        import std.path : baseName, buildPath, relativePath, stripExtension;

        this.file_classes = Path(buildPath(cast(string) output_dir,
                cast(string) file_prefix ~ "classes" ~ fileExt));
        this.file_components = Path(buildPath(cast(string) output_dir,
                cast(string) file_prefix ~ "components" ~ fileExt));
        this.file_style_output = Path(buildPath(cast(string) output_dir,
                cast(string) file_prefix ~ "style" ~ inclExt));
        this.file_style = Path(relativePath(cast(string) file_prefix ~ "style" ~ inclExt,
                cast(string) output_dir));
    }

    // -- Controller --

    bool doFile(in string filename, in string info) {
        return fileFilter.match(filename, (string s, string type) {
            logger.tracef("matcher --file-%s removed %s. Skipping", s, type);
        });
    }

    Flag!"genStyleInclFile" genStyleInclFile() {
        import std.file : exists;

        return cast(Flag!"genStyleInclFile")(do_style_incl && !exists(cast(string) file_style));
    }

    Path doComponentNameStrip(Path fname) {
        import std.path : dirName;
        import cpptooling.testdouble.header_filter : stripFile;

        if (do_comp_by_file) {
            return Path(stripFile(cast(string) fname, comp_strip));
        } else {
            return Path(stripFile((cast(string) fname).dirName, comp_strip));
        }
    }

    // -- Parameters --

    Path getOutputDirectory() const {
        return output_dir;
    }

    Parameters.Files getFiles() const {
        return Parameters.Files(file_classes, file_components, file_style, file_style_output);
    }

    FilePrefix getFilePrefix() const {
        return file_prefix;
    }

    Flag!"genClassMethod" genClassMethod() const {
        return gen_class_method;
    }

    Flag!"genClassParamDependency" genClassParamDependency() const {
        return gen_class_param_dep;
    }

    Flag!"genClassInheritDependency" genClassInheritDependency() const {
        return gen_class_inherit_dep;
    }

    Flag!"genClassMemberDependency" genClassMemberDependency() const {
        return gen_class_member_dep;
    }

    Flag!"doStyleIncl" doStyleIncl() const {
        return do_style_incl;
    }

    Flag!"doGenDot" doGenDot() const {
        return do_gen_dot;
    }

    // -- Products --

    void putFile(Path fname, PlantumlRootModule root) {
        fileData ~= FileData(fname, root.render());
    }

    void putFile(Path fname, PlantumlModule pm) {
        fileData ~= FileData(fname, pm.render());
    }
}

struct Lookup {
    import cpptooling.data.symbol : Container, USRType;
    import cpptooling.data : Location, LocationTag, TypeKind;

    private Container* container;

    auto kind(USRType usr) @safe {
        return container.find!TypeKind(usr);
    }

    auto location(USRType usr) @safe {
        return container.find!LocationTag(usr);
    }
}

ExitStatusType genUml(PlantUMLFrontend variant, string[] in_cflags,
        CompileCommandDB compile_db, Path[] inFiles, Flag!"skipFileError" skipFileError) {
    import std.algorithm : map, joiner;
    import std.array : array;
    import std.conv : text;
    import std.path : buildNormalizedPath, asAbsolutePath;
    import std.typecons : Yes;

    import cpptooling.data : CppRoot;
    import cpptooling.data.symbol : Container;
    import libclang_ast.context : ClangContext;

    import dextool.clang : reduceMissingFiles;
    import dextool.io : writeFileData;
    import dextool.plugin.backend.plantuml : Generator, UMLVisitor,
        UMLClassDiagram, UMLComponentDiagram, TransformToDiagram;
    import dextool.utility : prependDefaultFlags, PreferLang, analyzeFile;

    Container container;
    auto generator = Generator(variant, variant, variant);

    // note how the transform is connected with destinations via the generator
    // uml diagrams
    auto transform = new TransformToDiagram!(Controller, Parameters, Lookup)(variant,
            variant, Lookup(&container), generator.umlComponent, generator.umlClass);

    auto visitor = new UMLVisitor!(Controller, typeof(transform))(variant, transform, container);
    auto ctx = ClangContext(Yes.useInternalHeaders, Yes.prependParamSyntaxOnly);

    auto compDbRange() {
        if (compile_db.empty) {
            return fileRange(inFiles, Compiler("/usr/bin/c++"));
        }
        return compile_db.fileRange;
    }

    auto fixedDb = compDbRange.parse(defaultCompilerFilter).addCompiler(Compiler("/usr/bin/c++"))
        .addSystemIncludes.prependFlags(prependDefaultFlags(in_cflags, PreferLang.none)).array;

    auto limitRange = limitOrAllRange(fixedDb, inFiles.map!(a => cast(string) a).array)
        .reduceMissingFiles(fixedDb);

    if (!compile_db.empty && !limitRange.isMissingFilesEmpty) {
        foreach (a; limitRange.missingFiles) {
            logger.error("Unable to find any compiler flags for .", a);
        }
        return ExitStatusType.Errors;
    }

    AbsolutePath[] unable_to_parse;

    foreach (entry; limitRange.range) {
        auto analyze_status = analyzeFile(entry.cmd.absoluteFile,
                entry.flags.completeFlags, visitor, ctx);

        // compile error, let user decide how to proceed.
        if (analyze_status == ExitStatusType.Errors && skipFileError) {
            logger.errorf("Continue analyze...");
            unable_to_parse ~= entry.cmd.absoluteFile;
        } else if (analyze_status == ExitStatusType.Errors) {
            return ExitStatusType.Errors;
        }
    }

    if (unable_to_parse.length > 0) {
        // TODO be aware that no test exist for this logic
        import std.ascii : newline;
        import std.range : roundRobin, repeat;

        logger.errorf("Compile errors in the following files:\n%s\n",
                unable_to_parse.map!(a => (cast(string) a))
                .roundRobin(newline.repeat(unable_to_parse.length)).joiner().text);
    }

    transform.finalize();
    generator.process();

    debug {
        logger.trace(container.toString);
        logger.trace(generator.umlComponent.toString);
        logger.trace(generator.umlClass.toString);
    }

    return writeFileData(variant.fileData);
}