require_relative 'redmine_api'
require_relative 'gitea_api'

module RedmineToGitea

  class Mapping
    attr_accessor :user_names_proc
    attr_accessor :statuses_proc
    attr_accessor :closed_statuses_proc
    attr_accessor :priorities_proc

    def initialize(user_names_proc:, statuses_proc:, closed_statuses_proc:, priorities_proc: )
      @user_names_proc      = user_names_proc
      @statuses_proc        = statuses_proc
      @closed_statuses_proc = closed_statuses_proc
      @priorities_proc      = priorities_proc
    end

    def user_name(redmine_user_id)
      return nil if redmine_user_id.nil?

      user_names_proc.call(redmine_user_id)
    end

    def status(redmine_status_id)
      statuses_proc.call(redmine_status_id.to_i)
    end

    def status_closed?(redmine_status_id)
      closed_statuses_proc.call(redmine_status_id.to_i)
    end

    def priority(redmine_priority_id)
      priorities_proc.call(redmine_priority_id.to_i)
    end
  end

  class Settings
    attr_accessor :mapping
    attr_accessor :date_format
    attr_accessor :textile_to_markdown

    def initialize(mapping:, date_format:, textile_to_markdown: Proc.new { |x| x } )
      @mapping             = mapping
      @date_format         = date_format
      @textile_to_markdown = textile_to_markdown
    end
  end

  class Migrator
    attr_accessor :redmine_api
    attr_accessor :gitea_api
    attr_accessor :settings
    attr_accessor :issue_formatter

    def initialize(redmine_api:, gitea_api:, settings: Settings.new)
      @redmine_api      = redmine_api
      @gitea_api        = gitea_api
      @settings         = settings
      @issue_formatter  = IssueFormatter.new(
                            mapping: mapping,
                            date_format: settings.date_format,
                            textile_to_markdown: settings.textile_to_markdown
                          )
    end

    def reset_project(owner:, repo_payload:, collaborators: [])
      repo = repo_payload.fetch(:name)
      old_repository = gitea_api.get_repo(owner: owner, repo: repo)

      if old_repository.id
        gitea_api.delete_repository(owner: owner, repo: repo)
      end

      # gitea_api.create_org_repository(org: owner, repository: repo_payload)
      gitea_api.create_user_repository(payload: repo_payload, user: owner)

      collaborators.each do |collaborator|
        gitea_api.add_collaborator(
          owner: owner,
          repo: repo,
          collaborator: collaborator,
          payload: { permission: "write" }
        )
      end
    rescue => ex
      binding.pry
    end

    def issues(redmine_project:, gitea_owner:, gitea_repo:)
      remaining_results = true
      offset = 0
      limit = 25

      while remaining_results do
        result_set = redmine_api.get_issues(
          project_id: redmine_project,
          offset:     offset,
          limit:      limit
        )

        result_set.results.each do |result|
          import_issue(
            redmine_issue: redmine_api.get_issue(id: result.id),
            owner: gitea_owner,
            repo: gitea_repo
          )
        end
        offset = offset + result_set.results.size
        remaining_results = result_set.remaining_results?
      end
    rescue => ex
      binding.pry
    end

    private

    def mapping
      settings.mapping
    end

    def import_issue(redmine_issue:, owner:, repo:)
      gitea_issue = {
        "title"  => redmine_issue.subject,
        "body"   => issue_formatter.description(redmine_issue),
        "closed" => mapping.status_closed?(redmine_issue.status_id),
      }
      if redmine_issue.assigned_to
        assignee = mapping.user_name(redmine_issue.assigned_to)

        gitea_issue["assignee"]  = assignee
        gitea_issue["assignees"] = [assignee]
      end

      user = mapping.user_name(redmine_issue.author_id)

      created_gitea_issue = gitea_api.create_issue(
        payload: gitea_issue,
        owner:   owner,
        repo:    repo,
        user:    user
      )
      gitea_issue_number = created_gitea_issue.fetch("number")

      redmine_issue.journals.each do |journal|
        gitea_comment = {
          "body" => issue_formatter.comment(journal)
        }
        user_name = mapping.user_name(journal.user_id)

        gitea_api.create_comment(
          payload:  gitea_comment,
          owner:    owner,
          repo:     repo,
          issue:    gitea_issue_number,
          user:     user_name
        )
      end
    end
  rescue => ex
    binding.pry
  end

  class IssueFormatter
    attr_accessor :mapping
    attr_accessor :date_format
    attr_accessor :textile_to_markdown

    def initialize(mapping:, date_format: "%c", textile_to_markdown: )
      @mapping = mapping
      @date_format = date_format
      @textile_to_markdown = textile_to_markdown
    end

    def description(issue)
      issue_body  =   "> **Issue imported from forge.evolix.org on #{Time.now.strftime(date_format)}**"
      issue_body += "\n> * Project:    #{issue.project_name}"
      issue_body += "\n> * Issue:      #{issue.id}"
      issue_body += "\n> * Tracker:    #{issue.tracker_name}"
      issue_body += "\n> * Status:     #{issue.status_name}"
      issue_body += "\n> * Author:     #{issue.author_name}"
      issue_body += "\n> * Category:   #{issue.category_name}"
      issue_body += "\n> * Started at: #{DateTime.parse(issue.start_date).strftime(date_format)}"
      issue_body += "\n> * Done ratio: #{issue.done_ratio}"
      issue_body += "\n> * Created at: #{DateTime.parse(issue.created_on).strftime(date_format)}"
      issue_body += "\n> * Updated at: #{DateTime.parse(issue.updated_on).strftime(date_format)}"
      issue_body += "\n\n"
      issue_body += textile_to_markdown.call(issue.description)

      issue_body
    rescue => ex
      binding.pry
    end

    def comment(journal)
      comment_body  =   "> **Comment imported from forge.evolix.org on #{Time.now.strftime(date_format)}**"
      comment_body += "\n> * Author:     #{journal.user_name}" if journal.user_name
      comment_body += "\n> * Created at: #{DateTime.parse(journal.created_on).strftime(date_format)}" if journal.created_on

      comment_details(journal.details).each do |detail|
        comment_body += "\n> * #{detail}"
      end

      unless journal.notes.empty?
        comment_body += "\n\n"
        if journal.private_notes?
          comment_body += "_This note is private its content has not been imported_"
        else
          comment_body += textile_to_markdown.call(journal.notes)
        end
      end

      comment_body
    rescue => ex
      binding.pry
    end

    private

    def comment_details(details)
      results = []
      details.each do |detail|
        if detail['property'] == "attr"
          case detail['name']
          when "status_id" then
            old = mapping.status(detail['old_value'])
            new = mapping.status(detail['new_value'])
            results.push "Status: #{old} → #{new}"
          when "priority_id" then
            old = mapping.priority(detail['old_value'])
            new = mapping.priority(detail['new_value'])
            results.push "Priority: #{old} → #{new}"
          when "done_ratio" then
            old = detail['old_value']
            new = detail['new_value']
            results.push "Done ratio: #{old}% → #{new}%"
          when "project_id" then
            old = detail['old_value'] || "ø"
            new = detail['new_value'] || "ø"
            results.push "Project: #{old} → #{new}"
          # when "tracker_id" then
          #   old = detail['old_value'] || "ø"
          #   new = detail['new_value'] || "ø"
          #   results.push "Tracker: #{old} → #{new}"
          when "assigned_to_id" then
            old = mapping.user_name(detail['old_value']) || "ø"
            new = mapping.user_name(detail['new_value']) || "ø"
            results.push "Assigned to: #{old} → #{new}"
          when "fixed_version_id" then
            old = detail['old_value'] || "ø"
            new = detail['new_value'] || "ø"
            results.push "Version: #{old} → #{new}"
          when "subject", "description"
            next
          else
            old = detail['old_value'] || "ø"
            new = detail['new_value'] || "ø"
            results.push "#{detail['name']}: #{old} → #{new}"
          end
        elsif detail['property'] == "relation"
          results.push "Related to: #{detail['new_value']}"
        else
          next
        end
      end

      results
    end
  end

end