<template>
  <div class="show-if-initialized" :class="{ initialized }">
    <pre ref="editor" :class="styles"></pre>
  </div>
</template>

<script>
import ace from "ace-builds"
import "ace-builds/webpack-resolver"
import "ace-builds/src-noconflict/ext-language_tools"
import "ace-builds/src-noconflict/mode-graphqlschema"
import * as esprima from "esprima"
import debounce from "~/helpers/utils/debounce"
import {
  getPreRequestScriptCompletions,
  getTestScriptCompletions,
  performPreRequestLinting,
  performTestLinting,
} from "~/helpers/tern"

export default {
  props: {
    value: {
      type: String,
      default: "",
    },
    theme: {
      type: String,
      required: false,
      default: null,
    },
    options: {
      type: Object,
      default: () => {},
    },
    styles: {
      type: String,
      default: "",
    },
    completeMode: {
      type: String,
      required: true,
      default: "none",
    },
  },

  data() {
    return {
      initialized: false,
      editor: null,
      cacheValue: "",
    }
  },

  watch: {
    value(value) {
      if (value !== this.cacheValue) {
        this.editor.session.setValue(value, 1)
        this.cacheValue = value
        if (this.lint) this.provideLinting(value)
      }
    },
    theme() {
      this.initialized = false
      this.editor.setTheme(`ace/theme/${this.defineTheme()}`, () => {
        this.$nextTick()
          .then(() => {
            this.initialized = true
          })
          .catch(() => {
            // nextTick shouldn't really ever throw but still
            this.initialized = true
          })
      })
    },
    options(value) {
      this.editor.setOptions(value)
    },
  },

  mounted() {
    // const langTools = ace.require("ace/ext/language_tools")

    const editor = ace.edit(this.$refs.editor, {
      mode: `ace/mode/javascript`,
      enableBasicAutocompletion: true,
      enableLiveAutocompletion: true,
      ...this.options,
    })

    // Set the theme and show the editor only after it's been set to prevent FOUC.
    editor.setTheme(`ace/theme/${this.defineTheme()}`, () => {
      this.$nextTick()
        .then(() => {
          this.initialized = true
        })
        .catch(() => {
          // nextTIck shouldn't really ever throw but still
          this.initalized = true
        })
    })

    const completer = {
      getCompletions: (
        editor,
        _session,
        { row, column },
        _prefix,
        callback
      ) => {
        if (this.completeMode === "pre") {
          getPreRequestScriptCompletions(editor.getValue(), row, column)
            .then((res) => {
              callback(
                null,
                res.completions.map((r, index, arr) => ({
                  name: r.name,
                  value: r.name,
                  score: (arr.length - index) / arr.length,
                  meta: r.type,
                }))
              )
            })
            .catch(() => callback(null, []))
        } else if (this.completeMode === "test") {
          getTestScriptCompletions(editor.getValue(), row, column)
            .then((res) => {
              callback(
                null,
                res.completions.map((r, index, arr) => ({
                  name: r.name,
                  value: r.name,
                  score: (arr.length - index) / arr.length,
                  meta: r.type,
                }))
              )
            })
            .catch(() => callback(null, []))
        }
      },
    }

    editor.completers = [completer]

    if (this.value) editor.setValue(this.value, 1)

    this.editor = editor
    this.cacheValue = this.value

    editor.on("change", () => {
      const content = editor.getValue()
      this.$emit("input", content)
      this.cacheValue = content
      this.provideLinting(content)
    })

    this.provideLinting(this.value)
  },

  destroyed() {
    this.editor.destroy()
  },

  methods: {
    defineTheme() {
      if (this.theme) {
        return this.theme
      }
      const strip = (str) =>
        str.replace(/#/g, "").replace(/ /g, "").replace(/"/g, "")
      return strip(
        window
          .getComputedStyle(document.documentElement)
          .getPropertyValue("--editor-theme")
      )
    },

    provideLinting: debounce(function (code) {
      let results = []

      const lintFunc =
        this.completeMode === "pre"
          ? performPreRequestLinting
          : performTestLinting

      lintFunc(code)
        .then((semanticLints) => {
          results = results.concat(
            semanticLints.map((lint) => ({
              row: lint.from.line,
              column: lint.from.ch,
              text: `[semantic] ${lint.message}`,
              type: "error",
            }))
          )

          try {
            const res = esprima.parseScript(code, { tolerant: true })
            if (res.errors && res.errors.length > 0) {
              results = results.concat(
                res.errors.map((err) => {
                  const pos = this.editor.session
                    .getDocument()
                    .indexToPosition(err.index, 0)

                  return {
                    row: pos.row,
                    column: pos.column,
                    text: `[syntax] ${err.description}`,
                    type: "error",
                  }
                })
              )
            }
          } catch (e) {
            const pos = this.editor.session
              .getDocument()
              .indexToPosition(e.index, 0)
            results = results.concat([
              {
                row: pos.row,
                column: pos.column,
                text: `[syntax] ${e.description}`,
                type: "error",
              },
            ])
          }

          this.editor.session.setAnnotations(results)
        })
        .catch(() => {
          try {
            const res = esprima.parseScript(code, { tolerant: true })
            if (res.errors && res.errors.length > 0) {
              results = results.concat(
                res.errors.map((err) => {
                  const pos = this.editor.session
                    .getDocument()
                    .indexToPosition(err.index, 0)

                  return {
                    row: pos.row,
                    column: pos.column,
                    text: `[syntax] ${err.description}`,
                    type: "error",
                  }
                })
              )
            }
          } catch (e) {
            const pos = this.editor.session
              .getDocument()
              .indexToPosition(e.index, 0)
            results = results.concat([
              {
                row: pos.row,
                column: pos.column,
                text: `[syntax] ${e.description}`,
                type: "error",
              },
            ])
          }

          this.editor.session.setAnnotations(results)
        })
    }, 2000),
  },
}
</script>

<style lang="scss">
.show-if-initialized {
  @apply opacity-0;

  &.initialized {
    @apply opacity-100;
  }

  & > * {
    @apply transition-none;
  }
}
</style>
