nitx: introduce doc page search

[nit.git] / src / doc / doc_phases / doc_console.nit

# This file is part of NIT ( http://www.nitlanguage.org ).
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

# Nitx related components
#
# This module is a place holder for `nitx` related services.
# No `doc_phase` can be found here, only components used by Nitx tool.
module doc_console

import semantize
import doc::console_templates

# Nitx handles console I/O.
#
# Using `prompt`, the command line can be turned on an interactive tool.
class Nitx

        # ToolContext used to access options.
        var ctx: ToolContext

        # DocModel that contains the informations to display.
        var doc: DocModel

        # Comparator used to sort MEntities.
        var sorter = new MEntityNameSorter

        # Displays the welcome message and start prompt.
        fun start do
                welcome
                prompt
        end

        # Displays the welcome message and the list of loaded modules.
        fun welcome do
                print "Welcome in the Nit Index."
                print ""
                print "Loaded modules:"
                var mmodules = doc.mmodules.to_a
                sorter.sort(mmodules)
                for m in mmodules do
                        print "\t{m.name}"
                end
                print ""
                help
        end

        # Displays the list of available commands.
        fun help do
                print "\nCommands:"
                print "\tname\t\tlookup module, class and property with the corresponding 'name'"
                print "\tdoc: <name::space>\tdisplay the documentation page of 'namespace'"
                print "\t:h\t\tdisplay this help message"
                print "\t:q\t\tquit interactive mode"
                print ""
        end

        # Prompts the user for a command.
        fun prompt do
                printn ">> "
                do_query(sys.stdin.read_line)
                prompt
        end

        # Processes the query string and performs it.
        fun do_query(str: String) do
                var query = parse_query(str)
                var res = query.perform(self, doc)
                var page = query.make_results(self, res)
                print page.write_to_string
        end

        # Returns an `NitxQuery` from a raw query string.
        fun parse_query(str: String): NitxQuery do
                var query = new NitxQuery(str)
                if query isa NitxCommand then
                        query.execute(self)
                end
                return query
        end
end

# A query performed on Nitx.
#
# Queries are responsible to collect matching results and render them as a
# DocPage.
#
# Used as a factory to concrete instances.
interface NitxQuery

        # Original query string.
        fun query_string: String is abstract

        # Query factory.
        #
        # Will return a concrete instance of NitxQuery.
        new(query_string: String) do
                if query_string == ":q" then
                        return new NitxQuit
                else if query_string == ":h" then
                        return new NitxHelp
                else if query_string.has_prefix("comment:") then
                        return new CommentQuery(query_string)
                else if query_string.has_prefix("doc:") then
                        return new DocQuery(query_string)
                end
                return new CommentQuery("comment: {query_string}")
        end

        # Looks up the `doc` model and returns possible matches.
        fun perform(nitx: Nitx, doc: DocModel): Array[NitxMatch] is abstract

        # Pretty prints the results for the console.
        fun make_results(nitx: Nitx, results: Array[NitxMatch]): DocPage do
                var page = new DocPage("Results")
                page.root.add_child(new QueryResultArticle(self, results))
                return page
        end

        redef fun to_s do return query_string
end

# Something that matches a `NitxQuery`.
abstract class NitxMatch

        # Query matched by `self`.
        var query: NitxQuery

        # Pretty prints `self` for console.
        fun make_list_item: String is abstract
end

# A query that contains a meta command.
#
# In Nitx, commands are written such as `command: args...`.
abstract class MetaQuery
        super NitxQuery

        redef var query_string

        # Meta command used.
        var command: String is noinit

        # Arguments passed to the `command`.
        var args = new Array[String]

        init do
                # parse command
                var str = new FlatBuffer
                var i = 0
                while i < query_string.length do
                        var c = query_string[i]
                        i += 1
                        if c == ':' then break
                        str.add c
                end
                command = str.write_to_string
                # parse args
                args.add query_string.substring_from(i).trim
        end
end

# A match between a `NitxQuery` and a `MEntity`.
class MEntityMatch
        super NitxMatch

        # MEntity matched.
        var mentity: MEntity

        redef fun make_list_item do return mentity.cs_list_item
end

# A query to search a `MEntity` comment by its name or namespace.
class CommentQuery
        super MetaQuery

        redef fun perform(nitx, doc) do
                var name = args.first
                var res = new Array[NitxMatch]
                for mentity in doc.search_mentities(name) do
                        res.add new MEntityMatch(self, mentity)
                end
                return res
        end

        redef fun make_results(nitx, results) do
                var len = results.length
                if len == 1 then
                        var res = results.first.as(MEntityMatch)
                        var mentity = res.mentity
                        var page = new DocPage("Results")
                        var article = new DefinitionArticle(mentity)
                        article.cs_title = mentity.name
                        article.cs_subtitle = mentity.cs_declaration
                        page.root.add_child article
                        return page
                else
                        return super
                end
        end
end

# A query to search a Nitdoc documentation page by its name.
class DocQuery
        super MetaQuery

        redef fun perform(nitx, doc) do
                var res = new Array[NitxMatch]
                var name = args.first
                for page in doc.pages do
                        if name == "*" then # FIXME dev only
                                res.add new PageMatch(self, page)
                        else if page.title == name then
                                res.add new PageMatch(self, page)
                        else if page isa MEntityPage and page.mentity.cs_namespace == name then
                                res.add new PageMatch(self, page)
                        end
                end
                return res
        end

        redef fun make_results(nitx, results) do
                var len = results.length
                # FIXME how to render the pager for one worded namespaces like "standard"?
                if len == 1 then
                        var page = results.first.as(PageMatch).page
                        var pager = new Pager
                        pager.add page.write_to_string
                        pager.render
                        return page
                else
                        return super
                end
        end
end

# A match between a `DocPage` and a `MEntity`.
class PageMatch
        super NitxMatch

        # `DocPage` matched.
        var page: DocPage

        redef fun make_list_item do
                var page = self.page
                if page isa MEntityPage then
                        return page.mentity.cs_list_item
                end
                return " * {page.title}"
        end
end

# A query that contains a nitx command.
#
# These commands are prefixed with `:` and are used to control the execution of
# `nitx` like displaying the help or quiting.
interface NitxCommand
        super NitxQuery

        # Executes the command.
        fun execute(nitx: Nitx) is abstract
end

# Exits nitx.
class NitxQuit
        super NitxCommand

        redef fun execute(nitx) do exit 0
end

# Displays the help message.
class NitxHelp
        super NitxCommand

        redef fun execute(nitx) do nitx.help
end

## exploration

redef class DocModel

        # Lists all MEntities in the model.
        private var mentities: Collection[MEntity] is lazy do
                var res = new HashSet[MEntity]
                res.add_all mprojects
                res.add_all mgroups
                res.add_all mmodules
                res.add_all mclasses
                res.add_all mclassdefs
                res.add_all mproperties
                res.add_all mpropdefs
                return res
        end

        # Search MEntities that match `name` by their name or namespace.
        private fun search_mentities(name: String): Array[MEntity] do
                var res = new Array[MEntity]
                for mentity in mentities do
                        if mentity.name != name and mentity.cs_namespace != name then continue
                        res.add mentity
                end
                return res
        end
end

# display

# A `DocArticle` that displays query results.
private class QueryResultArticle
        super DocArticle

        # Query linked to the results to display.
        var query: NitxQuery

        # Results to display.
        var results: Array[NitxMatch]

        redef fun render_title do
                var len = results.length
                if len == 0 then
                        add "No result found for '{query.query_string}'..."
                else
                        add "# {len} result(s) for '{query.query_string}'".green.bold
                end
        end

        redef fun render_body do
                addn ""
                for result in results do
                        addn ""
                        addn result.make_list_item
                end
        end
end

# A Pager is used to display data into a unix `less` container.
private class Pager

        # Content to display.
        var content = new FlatBuffer

        # Adds text to the pager.
        fun add(text: String) do
                content.append(escape(text))
        end

        fun render do sys.system("echo \"{content}\" | less -r")

        fun escape(str: String): String
        do
                var b = new FlatBuffer
                for c in str.chars do
                        if c == '\n' then
                                b.append("\\n")
                        else if c == '\0' then
                                b.append("\\0")
                        else if c == '"' then
                                b.append("\\\"")
                        else if c == '\\' then
                                b.append("\\\\")
                        else if c == '`' then
                                b.append("'")
                        else if c.ascii < 32 then
                                b.append("\\{c.ascii.to_base(8, false)}")
                        else
                                b.add(c)
                        end
                end
                return b.to_s
        end
end