import * as LRU from 'lru-cache'
import { Theme } from 'monaco-textmate/dist/theme'
import { ITextmateThemePlus } from '.'

export enum CmToken {
    Atom = 'atom',
    Attribute = 'attribute',
    Bracket = 'bracket',
    Builtin = 'builtin',
    Comment = 'comment',
    Def = 'def',
    Error = 'error',
    Header = 'header',
    HR = 'hr',
    Keyword = 'keyword',
    Link = 'link',
    Meta = 'meta',
    Number = 'number',
    Operator = 'operator',
    Property = 'property',
    Qualifier = 'qualifier',
    Quote = 'quote',
    String = 'string',
    String2 = 'string-2',
    Tag = 'tag',
    Type = 'type',
    Variable = 'variable',
    Variable2 = 'variable-2',
    Variable3 = 'variable-3',
}


/**
 * Generates css style rules from TM theme
 * Backwards compatible with Codemirror tokens (this theme WILL apply to traditional Codemirror modes)
 */
export function cssTextFromTmTheme(rawTheme: ITextmateThemePlus): string {
    const theme = Theme.createFromRawTheme(rawTheme)
    const cccmTokenColors = {
        [CmToken.Atom]: theme.match('constant.language')[0].foreground,
        [CmToken.Attribute]: theme.match('entity.other.attribute-name')[0].foreground,
        [CmToken.Bracket]: theme.match('punctuation.definition.tag')[0].foreground,
        [CmToken.Builtin]: theme.match('support.function')[0].foreground,
        [CmToken.Comment]: theme.match('comment')[0].foreground,
        [CmToken.Def]: theme.match('entity.name.function')[0].foreground,
        [CmToken.Error]: null,
        [CmToken.Header]: null,
        [CmToken.HR]: null,
        [CmToken.Keyword]: theme.match('keyword')[0].foreground,
        [CmToken.Link]: null,
        [CmToken.Meta]: theme.match('meta')[0].foreground,
        [CmToken.Number]: theme.match('constant.numeric')[0].foreground,
        [CmToken.Operator]: theme.match('keyword.operator')[0].foreground,
        [CmToken.Property]: theme.match('variable.other.property')[0].foreground,
        [CmToken.Qualifier]: null,
        [CmToken.Quote]: null,
        [CmToken.String]: theme.match('string')[0].foreground,
        [CmToken.String2]: theme.match('string.regexp')[0].foreground,
        [CmToken.Tag]: theme.match('entity.name.tag')[0].foreground,
        [CmToken.Type]: theme.match('storage.type')[0].foreground,
        [CmToken.Variable]: theme.match('variable.other.object')[0].foreground,
        [CmToken.Variable2]: theme.match('support.class.builtin')[0].foreground,
        [CmToken.Variable3]: null,
    }

    const { name, settings, gutterSettings } = rawTheme
    const prefix = `.cm-s-${name}`
    const lines = []

    const { settings: generalSettings } = settings.find((rule) => !rule.scope) || {} as any
    if (generalSettings) {
        const { background, caret, foreground, lineHighlight, selection } = generalSettings
        lines.push(`${prefix}.CodeMirror {`)
        if (background) {
            lines.push(`\tbackground: ${background};`)
        }
        if (foreground) {
            lines.push(`\tcolor: ${foreground};`)
        }
        lines.push('}')

        if (caret) {
            lines.push(`${prefix} .CodeMirror-cursor { border-left-color: ${caret}; }`)
        }

        if (lineHighlight) {
            lines.push(`${prefix} .CodeMirror-activeline-background { background: ${lineHighlight}; }`)
        }

        if (selection) {
            lines.push(`${prefix} .CodeMirror-selected { background: ${selection}; }`)
        }
    }

    if (gutterSettings) {
        const { background, divider, foreground, lineActiveBackground, lineActiveForeground } = gutterSettings
        lines.push(`${prefix} .CodeMirror-gutters {`)
        if (background) {
            lines.push(`\tbackground: ${background};`)
        }
        if (divider) {
            lines.push(`\tborder-right-color: ${divider};`)
        }
        lines.push('}')

        if (foreground) {
            lines.push(`${prefix} .CodeMirror-linenumber { color: ${foreground}; }`)
        }

        if (lineActiveBackground) {
            lines.push(`${prefix} .CodeMirror-activeline .CodeMirror-activeline-gutter { background: ${lineActiveBackground}; }`)
        }

        if (lineActiveForeground) {
            lines.push(`${prefix} .CodeMirror-activeline .CodeMirror-linenumber { color: ${lineActiveForeground}; }`)
        }
    }
    const colorMap = theme.getColorMap()

    for (const token in cccmTokenColors) {
        const colorId = cccmTokenColors[token]
        if (colorId) {
            lines.push(`${prefix} .cm-${token} { color: ${colorMap[colorId]} }`)
        }
    }

    return lines
        .concat(...colorMap.map((color, i) => `${prefix} .cm-tm-${i} { color: ${color} }`))
        .join('\n')
}


const tmToCm = {
    comment: {
        $: CmToken.Comment,
    },

    constant: {
        // TODO: Revision
        $: CmToken.Def,
        character: {
            escape: {
                $: CmToken.String2,
            },
        },
        language: {
            $: CmToken.Atom,
        },
        numeric: {
            $: CmToken.Number,
        },
        other: {
            email: {
                link: {
                    $: CmToken.Link,
                },
            },
            symbol: {
                // TODO: Revision
                $: CmToken.Def,
            },
        },
    },

    entity: {
        name: {
            class: {
                $: CmToken.Def,
            },
            function: {
                $: CmToken.Def,
            },
            tag: {
                $: CmToken.Tag,
            },
            type: {
                $: CmToken.Type,
                class: {
                    $: CmToken.Variable,
                },
            },
        },
        other: {
            'attribute-name': {
                $: CmToken.Attribute,
            },
            'inherited-class': {
                // TODO: Revision
                $: CmToken.Def,
            },
        },
        support: {
            function: {
                // TODO: Revision
                $: CmToken.Def,
            },
        },
    },

    keyword: {
        $: CmToken.Keyword,
        operator: {
            $: CmToken.Operator,
        },
        other: {
            'special-method': CmToken.Def,
        },
    },
    punctuation: {
        $: CmToken.Operator,
        definition: {
            comment: {
                $: CmToken.Comment,
            },
            tag: {
                $: CmToken.Bracket,
            },
            // 'template-expression': {
            //     $: CodeMirrorToken.Operator,
            // },
        },
        // terminator: {
        //     $: CodeMirrorToken.Operator,
        // },
    },

    storage: {
        $: CmToken.Keyword,
    },

    string: {
        $: CmToken.String,
        regexp: {
            $: CmToken.String2,
        },
    },

    support: {
        class: {
            $: CmToken.Def,
        },
        constant: {
            $: CmToken.Variable2,
        },
        function: {
            $: CmToken.Def,
        },
        type: {
            $: CmToken.Type,
        },
        variable: {
            $: CmToken.Variable2,
            property: {
                $: CmToken.Property,
            },
        },
    },

    variable: {
        $: CmToken.Def,
        language: {
            // TODO: Revision
            $: CmToken.Variable3,
        },
        other: {
            object: {
                $: CmToken.Variable,
                property: {
                    $: CmToken.Property,
                },
            },
            property: {
                $: CmToken.Property,
            },
        },
        parameter: {
            $: CmToken.Def,
        },
    },
}

function walk(scopeSegments: string[], tree = tmToCm): CmToken {
    const first = scopeSegments.shift()
    const node = tree[first]
    if (node) {
        return walk(scopeSegments, node) || node.$ || null
    }
    return null
}

const dotRE = /\./
const cache = new LRU<string, CmToken>({ max: 2000 })
export function tmScopeToCmToken(scope: string): CmToken {
    if (!cache.has(scope)) {
        cache.set(scope, walk(scope.split(dotRE)))
    }
    return cache.get(scope)
}